02181nas a2200217 4500008004100000245009500041210006900136260001200205490001700217520144600234653001301680100001701693700001801710700001701728700001601745700001801761700001501779700002001794700001501814856013401829 2018 eng d00aDecentralized Trajectory Tracking Control for Soft Robots Interacting with the Environment0 aDecentralized Trajectory Tracking Control for Soft Robots Intera c06/20180 vEarly Access3 a

Despite the classic nature of the problem, trajectory

tracking for soft robots, i.e. robots with compliant elements

deliberately introduced in their design, still presents several

challenges. One of these is to design controllers which can

obtain sufficiently high performance while preserving the physical

characteristics intrinsic to soft robots. Indeed, classic control

schemes using high gain feedback actions fundamentally alter the

natural compliance of soft robots effectively stiffening them, thus

de facto defeating their main design purpose. As an alternative

approach, we consider here to use a low-gain feedback, while

exploiting feedforward components. In order to cope with the

complexity and uncertainty of the dynamics, we adopt a decentralized,

iteratively learned feedforward action, combined with

a locally optimal feedback control. The relative authority of the

feedback and feedforward control actions adapts with the degree

of uncertainty of the learned component. The effectiveness of the

method is experimentally verified on several robotic structures

and working conditions, including unexpected interactions with

the environment, where preservation of softness is critical for

safety and robustness.

10aRobotics1 aAngelini, F.1 aDella Santina1 aGarabini, M.1 aBianchi, M.1 aGasparri, G M1 aGrioli, G.1 aCatalano, M. G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-trajectory-tracking-control-soft-robots-interacting-environment.html00514nas a2200145 4500008003900000245006800039210006800107260005400175653001300229100001800242700002400260700001500284700001100299856005800310 2018 d00aDynamic Control of Soft Robots Interacting with the Environment0 aDynamic Control of Soft Robots Interacting with the Environment a24 - 28 April 2018, Livorno, ItalybIEEEc07/201810aRobotics1 aDella Santina1 aKatzschmann, R., K.1 aBicchi, A.1 aRus, D uhttps://ieeexplore.ieee.org/abstract/document/840489500587nas a2200193 4500008004100000245011000041210006900151260001200220490000700232653001200239653001300251100001100264700001300275700001700288700001300305700001100318700001500329856004900344 2017 eng d00aAsymmetric Bimanual Coordinate Control of Dual-Arm Exoskeleton Robots for Human Cooperative Manipulations0 aAsymmetric Bimanual Coordinate Control of DualArm Exoskeleton Ro c11/20170 v3410aHaptics10aRobotics1 aLi, Z.1 aChen, Z.1 aAjoudani, A.1 aYang, C.1 aSu, C.1 aBicchi, A. uhttps://ieeexplore.ieee.org/document/810334002034nas a2200145 4500008004100000245005100041210005100092260001200143520161600155653001301771100001701784700002301801700001501824856004901839 2017 eng d00aChoosing Poses for Force and Stiffness Control0 aChoosing Poses for Force and Stiffness Control c06/20173 a

In humanoids and other redundant robots interacting with the environment, one can often choose between different configurations and control parameters to achieve a given task. A classic tool to describe specifications of the desired force/displacement behavior in such problems is the stiffness ellipsoid, whose geometry is affected by the choice of parameters in both joint control and redundancy resolution—namely, gains and angles. As is well known, impedance control techniques can regulate gains to realize any desired shape of the Cartesian stiffness ellipsoid at the end-effector, so that robot geometry selection could appear secondary. However, humans do not use this possibility: To control the stiffness of our arms, we predominantly use arm configurations. Why is that, and does it makes sense to do the same in robots? To understand this discrepancy, we provide a more complete analysis of the task-space force/deformation behavior of compliant redundant arms to illustrate why the arm geometry plays a dominant role in interaction capabilities of robots. We introduce the notion of allowable Cartesian force/displacement (“stiffness feasibility”) regions (SFR) for compliant robots with given torque boundaries. We show that different robot configurations modify such regions and explore the role of robot geometry in achieving an appropriate SFR for the task at hand. The novel concepts and definitions are first illustrated in simulations. Experimental results are then provided to verify the effectiveness of the proposed Cartesian force and stiffness control.

10aRobotics1 aAjoudani, A.1 aTsagarakis, N., G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7951027/02174nas a2200229 4500008004100000022001400041245007300055210006900128260001200197300001200209490000700221520152100228653001301749100001801762700001601780700001501796700001701811700002001828700001701848700001501865856006401880 2017 eng d a1070-993200aControlling Soft Robots: Balancing Feedback and Feedforward Elements0 aControlling Soft Robots Balancing Feedback and Feedforward Eleme c05/2017 a75 - 830 v243 a

Soft robots (SRs) represent one of the most significant recent evolutions in robotics. Designed to embody safe and natural behaviors, they rely on compliant physical structures purposefully designed to embody desirable and sometimes variable impedance characteristics. This article discusses the problem of controlling SRs. We start by observing that most of the standard methods of robotic control—e.g., high-gain robust control, feedback linearization, backstepping, and active impedance control—effectively fight against or even completely cancel the physical dynamics of the system, replacing them with a desired model. This defeats the purpose of introducing physical compliance. After all, what is the point of building soft actuators if we then make them stiff by control? An alternative to such approaches can be conceived by observing humans, who can obtain good motion accuracy and repeatability while maintaining the intrinsic softness of their bodies. In this article, we show that an anticipative model of human motor control, using a feedforward action combined with low-gain feedback, can be used to achieve human-like behavior. We present an implementation of such an idea that uses iterative learning control. Finally, we present the experimental results of the application of such learned anticipative control to a physically compliant robot. The control application achieves the desired behavior much better than a classical feedback controller used for comparison.

10aRobotics1 aDella Santina1 aBianchi, M.1 aGrioli, G.1 aAngelini, F.1 aCatalano, M. G.1 aGarabini, M.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=793043801909nas a2200181 4500008004100000245009500041210006900136260001200205520135300217653001301570100001401583700001101597700001101608700001701619700001501636700001201651856006401663 2017 eng d00aCoordination Control of a Dual-arm Exoskeleton Robot Using Human Impedance Transfer Skills0 aCoordination Control of a Dualarm Exoskeleton Robot Using Human  c06/20173 a

This paper has developed a coordination control method for a dual-arm exoskeleton robot based on human impedance transfer skills, where the left (master) robot arm extracts the human limb impedance stiffness and position profiles, and then transfers the information to the right (slave) arm of the exoskeleton. A computationally efficient model of the arm endpoint stiffness behavior is developed and a co-contraction index is defined using muscular activities of a dominant antagonistic muscle pair. A reference command consisting of the stiffness and position profiles of the operator is computed and realized by one robot in real-time. Considering the dynamics uncertainties of the robotic exoskeleton, an adaptive-robust impedance controller in task space is proposed to drive the slave arm tracking the desired trajectories with convergent errors. To verify the robustness of the developed approach, a study of combining adaptive control and human impedance transfer control under the presence of unknown interactive forces is conducted. The experimental results of this paper suggest that the proposed control method enables the subjects to execute a coordination control task on a dual-arm exoskeleton robot by transferring the stiffness from the human arm to the slave robot arm, which turns out to be effective.

10aRobotics1 aHuang, B.1 aLi, Z.1 aWu, X.1 aAjoudani, A.1 aBicchi, A.1 aLiu, J. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=794458201761nas a2200193 4500008003900000245009400039210006900133260004100202520113300243653001301376100001701389700002001406700001701426700001701443700002001460700002301480700001501503856004901518 2017 d00aDesign and characterization of a novel high-compliance spring for robots with soft joints0 aDesign and characterization of a novel highcompliance spring for aMunich, Germany, 3-7 July 2017bIEEE3 a

Low stiffness elements have a number of applications in Soft Robotics, from Series Elastic Actuators (SEA) to torque sensors for compliant systems. In its general formulation, the design problem of elastic components is complex and depends on several variables: material properties, load range, shape factor and size constraints. Consequently, most of the spring designs presented in literature are based on heuristics or are optimized for specific working conditions. This work presents the design study and characterization of a scalable spoked elastic element with hinge tip constraints. We compared the proposed design with three existing spring principles, showing that the spoked solution is the convenient option for low-stiffness and low shape factor elastic elements. Therefore, a design analysis on the main scaling parameters of the spoked spring, namely number of spokes and type of constraints, is presented. Finally, an experimental characterization has been conducted on physical prototypes. The agreement among simulations and experimental results demonstrates the effectiveness of the proposed concept.

10aRobotics1 aNegrello, F.1 aCatalano, M. G.1 aGarabini, M.1 aPoggiani, M.1 aCaldwell, D. G.1 aTsagarakis, N., G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/8014029/01687nas a2200205 4500008003900000245007900039210006900118260003800187300001400225520106500239653001301304100001601317700001401333700001801347700001701365700002001382700001501402700001501417856004901432 2017 d00aDesign, control and validation of the variable stiffness exoskeleton FLExo0 aDesign control and validation of the variable stiffness exoskele aLondon, UK, 17-20 July 2017bIEEE a539 - 5463 a

In this paper we present the design of a one degree of freedom assistive platform to augment the strength of upper limbs. The core element is a variable stiffness actuator, closely reproducing the behavior of a pair of antagonistic muscles. The novelty introduced by this device is the analogy of its control parameters with those of the human muscle system, the threshold lengths. The analogy can be obtained from a proper tuning of the mechanical system parameters. Based on this, the idea is to control inputs by directly mapping the estimation of the muscle activations, e.g. via ElectroMyoGraphic(EMG) sensors, on the exoskeleton. The control policy resulting from this mapping acts in feedforward in a way to exploit the muscle-like dynamics of the mechanical device. Thanks to the particular structure of the actuator, the exoskeleton joint stiffness naturally results from that mapping. The platform as well as the novel control idea have been experimentally validated and the results show a substantial reduction of the subject muscle effort.

10aRobotics1 aMghames, S.1 aLaghi, M.1 aDella Santina1 aGarabini, M.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/8009304/01632nas a2200241 4500008003900000245006600039210006500105260004000170520094200210653001201152653001301164100001501177700001501192700001501207700001701222700001801239700001801257700002001275700001601295700001501311700001501326856004901341 2017 d00aDesign of an Under-Actuated Wrist Based on Adaptive Synergies0 aDesign of an UnderActuated Wrist Based on Adaptive Synergies aSingapore, 29 May-3 June 2017bIEEE3 a

An effective robotic wrist represents a key enabling element in robotic manipulation, especially in prosthetics. In this paper, we propose an under-actuated wrist system, which is also adaptable and allows to implement different under-actuation schemes. Our approach leverages upon the idea of soft synergies - in particular the design method of adaptive synergies - as it derives from the field of robot hand design. First we introduce the design principle and its implementation and function in a configurable test bench prototype, which can be used to demonstrate the feasibility of our idea. Furthermore, we report on results from preliminary experiments with humans, aiming to identify the most probable wrist pose during the pre-grasp phase in activities of daily living. Based on these outcomes, we calibrate our wrist prototype accordingly and demonstrate its effectiveness to accomplish grasping and manipulation tasks.

10aHaptics10aRobotics1 aCasini, S.1 aTincani, V1 aAverta, G.1 aPoggiani, M.1 aDella Santina1 aBattaglia, E.1 aCatalano, M. G.1 aBianchi, M.1 aGrioli, G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7989789/01691nas a2200205 4500008004100000245008100041210006900122260001200191300001600203490000600219520111000225653001201335653001301347100001601360700001101376700001701387700001701404700001501421856004901436 2017 eng d00a Enhancing Adaptive Grasping Through a Simple Sensor-Based Reflex Mechanism 0 aEnhancing Adaptive Grasping Through a Simple SensorBased Reflex  c07/2017 a1664 - 16710 v23 a

This paper presents an approach to achieve adaptive grasp of unknown objects whose position is only approximately known via point-cloud data. We exploit the adaptability of a soft robotic hand which can autonomously conform to the shape of a grasped object if properly approached. Once a grasp approach has been preliminarily planned based only on rough estimates of the object position, the hand is shaped to a pregrasp configuration. Before closing the hand, a sensor-based algorithm is applied that corrects the relative hand-object posture so as to enhance the probability that the object is uniformly approached by all fingers, thus avoiding undesired premature contacts. The algorithm minimizes the distance between the hand's fingerpads and the object by continuously controlling both the wrist pose and orientation and the hand closure. Experimental studies with a Kuka-LWR arm and a Pisa/IIT Softhand illustrate the benefit of the developed technique and the improvement in grasping performance with respect to open-loop execution of grasps planned on the basis of prior RGB-D cues only.

10aHaptics10aRobotics1 aLuberto, E.1 aWu, Y.1 aSantaera, G.1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7875417/00674nas a2200169 4500008003900000245009600039210006900135260005300204653001300257100001800270700001400288700001700302700001500319700002000334700001500354856013500369 2017 d00aEstimating Contact Forces from Postural Measures in a class of Under-Actuated Robotic Hands0 aEstimating Contact Forces from Postural Measures in a class of U aVancouver, Canada, September 24–28, 2017bIEEE10aRobotics1 aDella Santina1 aPiazza, C1 aSantaera, G.1 aGrioli, G.1 aCatalano, M. G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/estimating-contact-forces-postural-measures-class-under-actuated-robotic-hands.html01904nas a2200241 4500008004100000022001400041245007700055210006900132260001200201300001600213490000700229520121800236653001201454653001301466100001901479700001801498700001801516700001601534700001301550700001501563700001601578856006801594 2017 eng d a1534-432000aGrasp Performance of a Soft Synergy-Based Prosthetic Hand: A Pilot Study0 aGrasp Performance of a Soft SynergyBased Prosthetic Hand A Pilot c12/2017 a2407 - 24170 v253 a

Current prosthetic hands are frequently rejected in part due to limited functionality and versatility. We assessed the feasibility of a novel prosthetic hand, the SoftHand Pro (SHP), whose design combines soft robotics and hand postural synergies. Able-bodied subjects (n = 23) tracked cursor motion by opening and closing the SHP and performed a grasp-lift-hold-release (GLHR) task with a sensorized cylindrical object of variable weight. The SHP control was driven by electromyographic (EMG) signals from two antagonistic muscles. Although the time to perform the GLHR task was longer for the SHP than native hand for the first few trials (10.2 ± 1.4 s and 2.13 ± 0.09 s, respectively), performance was much faster on subsequent trials (~5 s). The SHP steady-state grip force was significantly modulated as a function of object weight (p <; 0.001). For the native hand, however, peak and steady-state grip forces were modulated to a greater extent (+68% and +91%, respectively). These changes were mediated by the modulation of EMG amplitude and co-contraction. These data suggest that the SHP has a promise for prosthetic applications and point-to-design modifications that could improve the SHP.

10aHaptics10aRobotics1 aGailey, A., S.1 aGodfrey, S.B.1 aBreighner, R.1 aAndrews, K.1 aZhao, K.1 aBicchi, A.1 aSantello, M uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=809424601991nas a2200265 4500008004100000022001400041245010900055210006900164260001200233300001200245490000700257520121600264653001201480653001301492100002101505700001701526700001601543700001801559700001801577700001701595700001401612700001501626700002001641856006401661 2017 eng d a1939-141200aAn Integrated Approach to Characterize the Behavior of a Human Fingertip in Contact with a Silica Window0 aIntegrated Approach to Characterize the Behavior of a Human Fing c01/2017 a123-1290 v103 a

Understanding the mechanisms of human tactual perception represents a challenging task in haptics and humanoid robotics. A classic approach to tackle this issue is to accurately and exhaustively characterize the mechanical behavior of human fingertip. The output of this characterization can then be exploited to drive the design of numerical models, which can be used to investigate in depth the mechanisms of human sensing. In this work, we present a novel integrated measurement technique and experimental set up for in vivo characterization of the deformation of the human fingertip at contact, in terms of contact area, force, deformation, and pressure distribution. The device presented here compresses the participant's fingertip against a flat surface, while the aforementioned measurements are acquired and experimental parameters such as velocity, finger orientation, and displacement (indentation) controlled. Experimental outcomes are then compared and integrated with the output of a 3D finite element (FE) model of the human fingertip, built upon existing validated models. The agreement between numerical and experimental data represents a validation for our approach.

10aHaptics10aRobotics1 aD'Angelo, M., L.1 aCannella, F.1 aBianchi, M.1 aD'Imperio, M.1 aBattaglia, E.1 aPoggiani, M.1 aRossi, G.1 aBicchi, A.1 aCaldwell, D. G. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=757958202581nas a2200181 4500008004100000245009500041210006900136260001200205300000900217520181500226653001302041100001802054700001602072700001902088700001702107700001502124856026002139 2017 eng d00aOn the Minimum-Time Control Problem for Differential Drive Robots with Bearing Constraints0 aMinimumTime Control Problem for Differential Drive Robots with B c04/2017 a1-273 a

This paper presents a study of analysis of minimum-time trajectories for a differential drive robot equipped with a fixed and limited field-of-view camera, which must keep a given landmark in view during maneuvers. Previous works have considered the same physical problem and provided a complete analysis/synthesis for the problem of determining the shortest paths. The main difference in the two cost functions (length vs. time) lays on the rotation on the spot. Indeed, this maneuver has zero cost in terms of length and hence leads to a 2D shortest path synthesis. On the other hand, in case of minimum time, the synthesis depends also on the orientations of the vehicle. In other words, the not zero cost of the rotation on the spot maneuvers leads to a 3D minimum-time synthesis. Moreover, the shortest paths have been obtained by exploiting the geometric properties of the extremal arcs, i.e., straight lines, rotations on the spot, logarithmic spirals and involute of circles. Conversely, in terms of time, even if the extremal arcs of the minimum-time control problem are exactly the same, the geometric properties of these arcs change, leading to a completely different analysis and characterization of optimal paths. In this paper, after proving the existence of optimal trajectories and showing the extremal arcs of the problem at hand, we provide the control laws that steer the vehicle along these arcs and the time-cost along each of them. Moreover, this being a crucial step toward numerical implementation, optimal trajectories are proved to be characterized by a finite number of switching points between different extremal arcs, i.e., the concatenations of extremal arcs with infinitely many junction times are shown to violate the optimality conditions.

10aRobotics1 aCristofaro, A1 aSalaris, P.1 aPallottino, L.1 aGiannoni, F.1 aBicchi, A. uhttp://download.springer.com/static/pdf/641/art%253A10.1007%252Fs10957-017-1110-7.pdf?originUrl=http%3A%2F%2Flink.springer.com%2Farticle%2F10.1007%2Fs10957-017-1110-7&token2=exp=1492507070~acl=%2Fstatic%2Fpdf%2F641%2Fart%25253A10.1007%25252Fs10957-017-11100608nas a2200169 4500008003900000245006900039210006700108260004400175300001400219653001300233100001500246700001900261700001700280700001500297700001400312856011200326 2017 d00aModular One-to-many Clutchable Actuator for a Soft Elbow Exosuit0 aModular Onetomany Clutchable Actuator for a Soft Elbow Exosuit aLondon, UK, July 17 - 20, 2017c07/2017 a1679-168510aRobotics1 aCanesi, M.1 aXiloyannis, M.1 aAjoudani, A.1 aBicchi, A.1 aMasia, L. uhttp://www.centropiaggio.unipi.it/publications/modular-one-many-clutchable-actuator-soft-elbow-exosuit.html02171nas a2200157 4500008003900000245008200039210006900121260000900190300001600199520168700215653001301902100001501915700001901930700001501949856004901964 2017 d00aNoninteracting Constrained Motion Planning and Control for Robot Manipulators0 aNoninteracting Constrained Motion Planning and Control for Robot bIEEE a4038 - 40433 a

In this paper we present a novel geometric approach
to motion planning for constrained robot systems.
This problem is notoriously hard, as classical sampling-based
methods do not easily apply when motion is constrained in
a zero-measure submanifold of the configuration space. Based
on results on the functional controllability theory of dynamical
systems, we obtain a description of the complementary spaces
where rigid body motions can occur, and where interaction
forces can be generated, respectively. Once this geometric setting
is established, the motion planning problem can be greatly
simplified. Indeed, we can relax the geometric constraint, i.e.,
replace the lower–dimensional constraint manifold with a fulldimensional
boundary layer. This in turn allows us to plan
motion using state-of-the-art methods, such as RRT*, on points
within the boundary layer, which can be efficiently sampled. On
the other hand, the same geometric approach enables the design
of a completely decoupled control scheme for interaction forces,
so that they can be regulated to zero (or any other desired
value) without interacting with the motion plan execution.
A distinguishing feature of our method is that it does not
use projection of sampled points on the constraint manifold,
thus largely saving in computational time, and guaranteeing
accurate execution of the motion plan. An explanatory example
is presented, along with an experimental implementation of the
method on a bimanual manipulation workstation.

10aRobotics1 aBonilla, M1 aPallottino, L.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7989463/02059nas a2200193 4500008004100000245007500041210006900116260001200185300001200197490000600209520150800215653001201723653001301735100001301748700001701761700001501778700002301793856004901816 2017 eng d00aOnline Model Based Estimation of Complete Joint Stiffness of Human Arm0 aOnline Model Based Estimation of Complete Joint Stiffness of Hum c01/2018 a84 - 910 v33 a

The endpoint stiffness of the human arm has been long recognized as a key component ensuring the quasi-static stability of the arm physical interactions with the external world. Similarly, the understanding of the joint stiffness behavior can provide complementary insights, e.g., on the underlying stiffness regulation principles across different joints including the nullspace stiffness profiles. Traditionally, the experimental modeling and estimation of the human arm joint stiffness is achieved by the transformation of the identified arm endpoint stiffness to the joint coordinates. Due to the underlying kinematic redundancy, the obtained joint stiffness matrix is rank-deficient which implies that the information in the joint stiffness matrix is incomplete. While in robotics applications this issue can be addressed by designing a desired nullspace stiffness behavior through appropriate projections, the use of a similar technique in the identification of human joint stiffness profile is meaningless. Hence, the first objective of this work is to address this issue by developing a novel technique to identify the complete and physiologically meaningful joint stiffness of human arm. Second, we present a model-based online estimation technique to estimate the seven-dimensional complete joint stiffness in various arm poses and activation levels of the two dominant arm muscles that correspond to the geometric and volume modifications of the joint stiffness profile, respectively.

10aHaptics10aRobotics1 aFang, C.1 aAjoudani, A.1 aBicchi, A.1 aTsagarakis, N., G. uhttp://ieeexplore.ieee.org/document/7990237/00580nas a2200145 4500008003900000245007500039210006900114260004700183653001300230100001300243700001700256700001500273700002300288856012300311 2017 d00aOnline Model Based Estimation of Complete Joint Stiffness of Human Arm0 aOnline Model Based Estimation of Complete Joint Stiffness of Hum aVancouver, Canada, September 24–28, 201710aRobotics1 aFang, C.1 aAjoudani, A.1 aBicchi, A.1 aTsagarakis, N., G. uhttp://www.centropiaggio.unipi.it/publications/online-model-based-estimation-complete-joint-stiffness-human-arm.html-002408nas a2200241 4500008004100000245007300041210006900114260001200183520171500195653001201910653001301922100001801935700001601953700001501969700001501984700001401999700001302013700001802026700002002044700001602064700001502080856007102095 2017 eng d00aPostural Hand Synergies during Environmental Constraint Exploitation0 aPostural Hand Synergies during Environmental Constraint Exploita c08/20173 a

Humans are able to intuitively exploit the shape of an object and environmental constraints to achieve stable grasps and perform dexterous manipulations. In doing that, a vast range of kinematic strategies can be observed. However, in this work we formulate the hypothesis that such ability can be described in terms of a synergistic behavior in the generation of hand postures, i.e., using a reduced set of commonly used kinematic patterns. This is in analogy with previous studies showing the presence of such behavior in different tasks, such as grasping. We investigated this hypothesis in experiments performed by six subjects, who were asked to grasp objects from a flat surface. We quantitatively characterized hand posture behavior from a kinematic perspective, i.e., the hand joint angles, in both pre-shaping and during the interaction with the environment. To determine the role of tactile feedback, we repeated the same experiments but with subjects wearing a rigid shell on the fingertips to reduce cutaneous afferent inputs. Results show the persistence of at least two postural synergies in all the considered experimental conditions and phases. Tactile impairment does not alter significantly the first two synergies, and contact with the environment generates a change only for higher order Principal Components. A good match also arises between the first synergy found in our analysis and the first synergy of grasping as quantified by previous work. The present study is motivated by the interest of learning from the human example, extracting lessons that can be applied in robot design and control. Thus, we conclude with a discussion on implications for robotics of our findings.

10aHaptics10aRobotics1 aDella Santina1 aBianchi, M.1 aAverta, G.1 aCiotti, S.1 aArapi, V.1 aFani, S.1 aBattaglia, E.1 aCatalano, M. G.1 aSantello, M1 aBicchi, A. uhttps://www.frontiersin.org/articles/10.3389/fnbot.2017.00041/full01807nas a2200181 4500008003900000020002200039245008800061210006900149520124000218653001301458100001401471700001801485700001401503700001501517700002001532700001501552856005801567 2017 d a978-1-5386-2296-400aPreliminary results toward a naturally controlled multi-synergistic prosthetic hand0 aPreliminary results toward a naturally controlled multisynergist3 a

Robotic hands embedding human motor control principles in their mechanical design are getting increasing interest thanks to their simplicity and robustness, combined with good performance. Another key aspect of these hands is that humans can use them very effectively thanks to the similarity of their behavior with real hands. Nevertheless, controlling more than one degree of actuation remains a challenging task. In this paper, we take advantage of these characteristics in a multi-synergistic prosthesis. We propose an integrated setup composed of Pisa/IIT SoftHand 2 and a control strategy which simultaneously and proportionally maps the human hand movements to the robotic hand. The control technique is based on a combination of non-negative matrix factorization and linear regression algorithms. It also features a real-time continuous posture compensation of the electromyographic signals based on an IMU. The algorithm is tested on five healthy subjects through an experiment in a virtual environment. In a separate experiment, the efficacy of the posture compensation strategy is evaluated on five healthy subjects and, finally, the whole setup is successfully tested in performing realistic daily life activities.

10aRobotics1 aRossi, M.1 aDella Santina1 aPiazza, C1 aGrioli, G.1 aCatalano, M. G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/abstract/document/8009437/02018nas a2200229 4500008004100000022001500041245010300056210006900159300001200228490000700240520132900247653001301576100001801589700001401607700002101621700001501642700002001657700001501677700001701692700001501709856006401724 2017 eng d a1070-9932 00aThe Quest for Natural Machine Motion: An Open Platform to Fast-Prototyping Articulated Soft Robots0 aQuest for Natural Machine Motion An Open Platform to FastPrototy a48 - 560 v243 a
Soft robots are one of the most significant recent evolutions in robotics. They rely on compliant physical structures purposefully designed to embody desired characteristics. Since their introduction, they have shown remarkable applicability in overcoming their rigid counterparts in such areas as interaction with humans, adaptability, energy efficiency, and maximization of peak performance. Nonetheless, we believe
that research on novel soft robot applications is still slowed by the difficulty in obtaining or developing a working soft robot structure to explore novel applications.
In this article, we present the Natural Machine Motion Initiative (NMMI), a modular open platform that aims to provide the scientific community with tools for fast and easy prototyping of articulated soft robots. Such a platform is composed of three main open hardware modules: the Qbmoves variable-stiffness actuators (VSAs) to build the main robotic structure, soft end effectors (EEs) to interact with the world, and a pool of application-specific add-ons. We also discuss many novel uses of the platform to rapidly prototype (RP) and test new robotic structures with original soft capabilities, and we propose NMMI- based experiments.
10aRobotics1 aDella Santina1 aPiazza, C1 aGasparri, G., M.1 aBonilla, M1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=785769200686nas a2200217 4500008004100000022001400041245011700055210006900172260001200241653001200253653001300265100001400278700002000292700001900312700001400331700001500345700001600360700001300376700001500389856006400404 2017 eng d a1070-993200aThe SoftHand Pro-H: A Hybrid Body-Controlled, Electrically Powered Hand Prosthesis for Daily Living and Working 0 aSoftHand ProH A Hybrid BodyControlled Electrically Powered Hand  c11/201710aHaptics10aRobotics1 aPiazza, C1 aCatalano, M. G.1 aGodfrey, S. B.1 aRossi, M.1 aGrioli, G.1 aBianchi, M.1 aZhao, K.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=811063400573nas a2200145 4500008003900000245007000039210006900109260005300178653001300231100001400244700001700258700002000275700001500295856011700310 2017 d00aTele-Impedance with Force Feedback under Communication Time Delay0 aTeleImpedance with Force Feedback under Communication Time Delay aVancouver, Canada, September 24–28, 2017bIEEE10aRobotics1 aLaghi, M.1 aAjoudani, A.1 aCatalano, M. G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tele-impedance-force-feedback-under-communication-time-delay.html01695nas a2200157 4500008004100000245007600041210006900117260004000186520118200226653001301408100001701421700001801438700001701456700001501473856004901488 2017 eng d00aTowards Minimum-Information Adaptive Controllers for Robot Manipulators0 aTowards MinimumInformation Adaptive Controllers for Robot Manipu aMay 24–26 2017, Seattle USAbIEEE3 a

The aim of this paper is to move a step in the direction of determining the minimum amount of information needed to control a robot manipulator within the framework of adaptive control. Recent innovations in the state of the art show how global asymptotic trajectory tracking can be achieved despite the presence of uncertainties in the kinematic and dynamic models of the robot. However, a clear distinction between
which parameters can be included among the uncertainties, and which parameters can not, has not been drawn yet. Since most of the adaptive control algorithms are built on linearly parameterized models, we propose to reformulate the problem as finding a procedure to determine whether and how a given dynamical system can be linearly parameterized with respect to a specific set of parameters.
Within this framework, we show how the trajectory tracking problem of a manipulator can be accomplished with the only knowledge of the number of joints of the manipulator. As an illustrative example, we present the end-effector trajectory tracking control of a robot initialized with the kinematic model of a different robot.

10aRobotics1 aMarcucci, T.1 aDella Santina1 aGabiccini, M1 aBicchi, A. uhttps://ieeexplore.ieee.org/document/796360203800nas a2200481 4500008004100000022001400041245007800055210006900133260001200202300001100214490000700225520254400232653001302776100002302789700002002812700001702832700001302849700002002862700001602882700001602898700001702914700001502931700001902946700001502965700001902980700001602999700001503015700001603030700001103046700001603057700001703073700001703090700002003107700001603127700001903143700001903162700001403181700001503195700001503210700001403225700001703239856006203256 2017 eng d a1556-496700aWALK-MAN: A High-Performance Humanoid Platform for Realistic Environments0 aWALKMAN A HighPerformance Humanoid Platform for Realistic Enviro c06/2017 a1 - 340 v343 a

In this work, we present WALK-MAN, a humanoid platform that has been developed to operate in realistic unstructured environment, and demonstrate new skills including powerful manipulation, robust balanced locomotion, high-strength capabilities, and physical sturdiness. To enable these capabilities, WALK-MAN design and actuation are based on the most recent advancements of series elastic actuator drives with unique performance features that differentiate the robot from previous state-of-the-art compliant actuated robots. Physical interaction performance is benefited by both active and passive adaptation, thanks to WALK-MAN actuation that combines customized high-performance modules with tuned torque/velocity curves and transmission elasticity for high-speed adaptation response and motion reactions to disturbances. WALK-MAN design also includes innovative design optimization features that consider the selection of kinematic structure and the placement of the actuators with the body structure to maximize the robot performance. Physical robustness is ensured with the integration of elastic transmission, proprioceptive sensing, and control. The WALK-MAN hardware was designed and built in 11 months, and the prototype of the robot was ready four months before DARPA Robotics Challenge (DRC) Finals. The motion generation of WALK-MAN is based on the unified motion-generation framework of whole-body locomotion and manipulation (termed loco-manipulation). WALK-MAN is able to execute simple loco-manipulation behaviors synthesized by combining different primitives defining the behavior of the center of gravity, the motion of the hands, legs, and head, the body attitude and posture, and the constrained body parts such as joint limits and contacts. The motion-generation framework including the specific motion modules and software architecture is discussed in detail. A rich perception system allows the robot to perceive and generate 3D representations of the environment as well as detect contacts and sense physical interaction force and moments. The operator station that pilots use to control the robot provides a rich pilot interface with different control modes and a number of teleoperated or semiautonomous command features. The capability of the robot and the performance of the individual motion control and perception modules were validated during the DRC in which the robot was able to demonstrate exceptional physical resilience and execute some of the tasks during the competition.

10aRobotics1 aTsagarakis, N., G.1 aCaldwell, D. G.1 aNegrello, F.1 aChoi, W.1 aBaccelliere, L.1 aLoc, V., G.1 aNoorden, J.1 aMuratore, L.1 aMargan, A.1 aCardellino, A.1 aNatale, L.1 aHoffman, Mingo1 aDallali, H.1 aKashiri, N1 aMalzahn, J.1 aLee, J1 aKryczka, P.1 aKanoulas, D.1 aGarabini, M.1 aCatalano, M. G.1 aFerrati, M.1 aVarricchio, V.1 aPallottino, L.1 aPavan, C.1 aBicchi, A.1 aSettimi, A1 aRocchi, A1 aAjoudani, A. uhttp://onlinelibrary.wiley.com/doi/10.1002/rob.21702/epdf01767nas a2200169 4500008004100000022002200041245003200063210003200095260001300127300001200140490000600152520132300158653001301481100002201494700001501516856006601531 2016 eng d a978-3-319-32550-700aActuators for Soft Robotics0 aActuators for Soft Robotics bSpringer a499-5300 vB3 a

Although we do not know as yet how robots of the future will look like exactly, most of us are sure that they will not resemble the heavy, bulky, rigid machines dangerously moving around in old-fashioned industrial automation. There is a growing consensus, in the research community as well as in expectations from the public, that robots of the next generation will be physically compliant and adaptable machines, closely interacting with humans and moving safely, smoothly and efficiently – in other terms, robots will be soft.

This chapter discusses the design, modeling and control of actuators for the new generation of soft robots, which can replace conventional actuators in applications where rigidity is not the first and foremost concern in performance. The chapter focuses on the technology, modeling, and control of lumped parameters of soft robotics, that is, systems of discrete, interconnected, and compliant elements. Distributed parameters, snake-like and continuum soft robotics, are presented in Chap. 20, while Chap. 23 discusses in detail the biomimetic motivations that are often behind soft robotics.

10aRobotics1 aAlbu-Schaeffer, A1 aBicchi, A. uhttp://link.springer.com/chapter/10.1007/978-3-319-32552-1_2102880nas a2200229 4500008004100000245015000041210006900191260001200260490000700272520216800279653001202447653001302459100001302472700001602485700001302501700001802514700001402532700001502546700001502561700001602576856005802592 2016 eng d00aAssessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-inspired Robotic Hand for Prosthetic Applications0 aAssessment of Myoelectric Controller Performance and Kinematic B c10/20160 v103 a

Myoelectric-artificial limbs can significantly advance the state of the art in prosthetics, since they can be used to control mechatronic devices through muscular activity in a way that mimics how the subjects used to activate their muscles before limb loss. However, surveys indicate that dissatisfaction with the functionality of terminal devices underlies the widespread abandonment of prostheses. We believe that one key factor to improve acceptability of prosthetic devices is to attain human-likeness of prosthesis movements, a goal which is being pursued by research on social and human-robot interactions. Therefore, to reduce early abandonment of terminal devices, we propose that controllers should be designed such as to ensure effective task accomplishment in a natural fashion. In this work, we have analyzed and compared the performance of three types of myoelectric controller algorithms based on surface electromyography to control an under-actuated and multi-degrees of freedom prosthetic hand, the SoftHand Pro. The goal of the present study was to identify the myoelectric algorithm that best mimics the native hand movements. As a preliminary step, we first quantified the repeatability of the SoftHand Pro finger movements and identified the electromyographic recording sites for able-bodied individuals with the highest signal-to-noise ratio from two pairs of muscles, i.e. flexor digitorum superficialis/extensor digitorum communis, and flexor carpi radialis/extensor carpi ulnaris. Able-bodied volunteers were then asked to execute reach-to-grasp movements, while electromyography signals were recorded from flexor digitorum superficialis/extensor digitorum communis as this was identified as the muscle pair characterized by high signal-to-noise ratio and intuitive control. Subsequently, we tested three myoelectric controllers that mapped electromyography signals to position of the SoftHand Pro. We found that a differential electromyography-to-position mapping ensured the highest coherence with hand movements. Our results represent a first step towards a more effective and intuitive control of myoelectric hand prostheses.

10aHaptics10aRobotics1 aFani, S.1 aBianchi, M.1 aJain, S.1 aNeto, Pimenta1 aBoege, S.1 aGrioli, G.1 aBicchi, A.1 aSantello, M uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5066092/02143nas a2200229 4500008004100000245007100041210006700112260001200179300001600191490000700207520149200214653001201706653001301718100001901731700001601750700001401766700001701780700001601797700001401813700001501827856007101842 2016 eng d00aThe Change in Fingertip Contact Area as a Novel Proprioceptive Cue0 aChange in Fingertip Contact Area as a Novel Proprioceptive Cue c05/2016 a1159–11630 v263 a

Humans, many animals, and certain robotic hands have deformable fingertip pads. Deformable pads have the advantage of conforming to the objects that are being touched, ensuring a stable grasp for a large range of forces and shapes. Pad deformations change with finger displacements during touch. Pushing a finger against an external surface typically provokes an increase of the gross contact area, potentially providing a relative motion cue, a situation comparable to looming in vision. The rate of increase of the area of contact also depends on the compliance of the object. Because objects normally do not suddenly change compliance, participants may interpret an artificially induced variation in compliance, which coincides with a change in the gross contact area, as a change in finger displacement, and consequently they may misestimate their finger’s position relative to the touched object. To test this, we asked participants to compare the perceived displacements of their finger while contacting an object varying pseudo-randomly in compliance from trial to trial. Results indicate a bias in the perception of finger displacement induced by the change in compliance, hence in contact area, indicating that participants interpreted the altered cutaneous input as a cue to proprioception. This situation highlights the capacity of the brain to take advantage of knowledge of the mechanical properties of the body and of the external environment.

10aHaptics10aRobotics1 aMoscatelli, A.1 aBianchi, M.1 aSerio, A.1 aTerekhov, A.1 aHayward, V.1 aErnst, M.1 aBicchi, A. uhttp://www.sciencedirect.com/science/article/pii/S096098221630134801522nas a2200193 4500008004100000245007100041210006900112260001200181300001600193490000700209520094800216653002101164653001301185100001701198700001501215700001501230700001501245856006801260 2016 eng d00aConvergence Analysis of Distributed Set-Valued Information Systems0 aConvergence Analysis of Distributed SetValued Information System c06/2016 a1477 - 14910 v613 a
This paper focuses on the convergence of information in distributed systems of agents communicating over a network.
The information on which the convergence is sought is not represented by real numbers, as often in the literature, rather by sets. The dynamics of the evolution of information across the network is accordingly described by set-valued iterative maps. While the study of convergence of set-valued iterative maps is highly complex in general, this paper focuses on Boolean maps, which are comprised of arbitrary combinations of unions, intersections, and complements of sets. For these important class of systems, we provide tools to study both global and local convergence. A distributed geographic information system, leading to successful information reconstruction from partial and corrupted data, is used to illustrate the applications of the proposed methods.
10aEmbedded Control10aRobotics1 aFagiolini, A1 aDubbini, N1 aMartini, S1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=727207500645nas a2200169 4500008004500000245008200045210006900127260003400196300001200230653001300242100001300255700001400268700001700282700001100299700001500310856015000325 2016 engldsh 00aDevelopment of a robotic teaching interface for human to human skill transfer0 aDevelopment of a robotic teaching interface for human to human s aDanjeon, KoreabIEEEc11/2016 a710-71610aRobotics1 aYang, C.1 aLiang, P.1 aAjoudani, A.1 aLi, Z.1 aBicchi, A. uhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-85006355804&doi=10.1109%2fIROS.2016.7759130&partnerID=40&md5=7f982e3eb493c1a6047d1dcc2acbe20800907nas a2200301 4500008004100000245012600041210006900167260001200236300000900248490000700257653001200264653001300276100001600289700001600305700001700321700001700338700001700355700002000372700001400392700001900406700001700425700001500442700002100457700002200478700001900500700001500519856007100534 2016 eng d00aHand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands0 aHand synergies Integration of robotics and neuroscience for unde c07/2016 a1-230 v1710aHaptics10aRobotics1 aSantello, M1 aBianchi, M.1 aGabiccini, M1 aRicciardi, E1 aSalvietti, G1 aPrattichizzo, D1 aErnst, M.1 aMoscatelli, A.1 aJorntell, H.1 aKappers, A1 aKyriakopulos, K.1 aAlbu-Schaeffer, A1 aCastellini, C.1 aBicchi, A. uhttp://www.sciencedirect.com/science/article/pii/S157106451600026900597nas a2200181 4500008003900000245009300039210006900132260000900201653001300210100001700223700001700240700002000257700001600277700002000293700001500313700002300328856006400351 2016 d00aA Modular Compliant Actuator for Emerging High Performance and Fall-Resilient Humanoids0 aModular Compliant Actuator for Emerging High Performance and Fal bIEEE10aRobotics1 aNegrello, F.1 aGarabini, M.1 aCatalano, M. G.1 aMalzahn, J.1 aCaldwell, D. G.1 aBicchi, A.1 aTsagarakis, N., G. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=736356700983nas a2200361 4500008004100000245008000041210006900121260001200190490000700202653001300209100001600222700002000238700002000258700001400278700001200292700001500304700002200319700001700341700001900358700002100377700001500398700002100413700001400434700001500448700001500463700001400478700001500492700001500507700001300522700001800535700001900553856004900572 2016 eng d00aNo More Heavy Lifting: Robotic Solutions to the Container Unloading Problem0 aNo More Heavy Lifting Robotic Solutions to the Container Unloadi c08/20160 v2310aRobotics1 aStoyanov, T1 aVaskeviciusz, N1 aMueller, C., A.1 aFromm, T.1 aKrug, R1 aTincani, V1 aMojtahedzadeh, R.1 aKunaschk, S.1 aErnits, R., M.1 aCanelhas, D., R.1 aBonilla, M1 aSchwertfeger, S.1 aBonini, M1 aHalfar, H.1 aPathak, K.1 aRohde, M.1 aFantoni, G1 aBicchi, A.1 aBirk, A.1 aLilienthal, A1 aEchelmeyer, W. uhttps://ieeexplore.ieee.org/document/755353102465nas a2200217 4500008004500000245006700045210006600112260002800178300001600206520181400222653001202036653001302048100001702061700001702078700001702095700001402112700001802126700002002144700001502164856006802179 2016 engldsh 00aReflex Control of the Pisa/IIT SoftHand during Object Slippage0 aReflex Control of the PisaIIT SoftHand during Object Slippage aStockholm, SwedenbIEEE a1972 - 19793 a

In this work, to guarantee the Pisa/IIT SoftHand’s

grasp robustness against slippage, three reflex control modes,

namely Current, Pose and Impedance, are implemented and

experimentally evaluated. Towards this objective, ThimbleSense

fingertip sensors are designed and integrated into the thumb

and middle fingers of the SoftHand for real-time detection and

control of the slippage. Current reflex regulates the restoring

grasp forces of the hand by modulating the motor’s current

profile according to an update law. Pose and Impedance reflex

modes instead replicate this behaviour by implementing an

impedance control scheme. The difference between the two

latter is that the stiffness gain in Impedance reflex mode is

being varied in addition to the hand pose, as a function of

the slippage on the fingertips. Experimental setup also includes

a seven degrees-of-freedom robotic arm to realize consistent

trajectories (e.g. lifting) among three control modes for the sake

of comparison. Different test objects are considered to evaluate

the efficacy of the proposed reflex modes in our experimental

setup. Results suggest that task-appropriate restoring forces

can be achieved using Impedance reflex due to its capability

in demonstrating instantaneous and rather smooth reflexive

behaviour during slippage. Preliminary experiments on five

healthy human subjects provide evidence on the similarity of the

control concepts exploited by the humans and the one realized

by the Impedance reflex, highlighting its potential in prosthetic

applications.

10aHaptics10aRobotics1 aAjoudani, A.1 aHocaoglu, E.1 aAltobelli, A1 aRossi, M.1 aBattaglia, E.1 aTsagarakis, N G1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=748734401805nas a2200217 4500008003900000020002300039245009300062210006900155260004300224520111600267653001301383100002101396700001601417700001701433700001901450700002001469700001501489700001901504700001501523856004901538 2016 d a978-1-5090-4718-5 00aRobust Optimization of System Compliance for Physical Interaction in Uncertain Scenarios0 aRobust Optimization of System Compliance for Physical Interactio aCancun, Mexico, 15-17 Nov. 2016 bIEEE3 a

Compliance in robot design and control is often introduced to improve the robot performance in tasks where interaction with environment or human is required. However a rigorous method to choose the correct level of compliance is still not available. In this work we use robust optimization as a tool to select the optimal compliance value in a robotenvironment interaction scenario under uncertainties. We propose an approach that can be profitably applied on a variety of tasks, e.g.manipulation tasks or locomotion tasks. The aim is to minimize the forces of interaction considering model constraints and uncertainties. Numerical results show that: i) in case of perfect knowledge of the environment stiff robots behave better in terms of force minimization, ii) in case of uncertainties the optimal stiffness of the robot is lower than the previous case and optimal solutions provide a faster task accomplishment, iii) the optimal stiffness decreases as a function of the uncertainty measure. Experiments are carried out in a realistic set-up in case of bi-manual object handover.

10aRobotics1 aGasparri, G., M.1 aFabiani, F.1 aGarabini, M.1 aPallottino, L.1 aCatalano, M. G.1 aGrioli, G.1 aPersichini, R.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7803381/01277nas a2200205 4500008004500000245005900045210005900104260002200163300001200185490007200197520062200269653001300891100001700904700001800921700001600939700002000955700001500975700001500990856006601005 2016 engldsh 00aSoft Robots that Mimic the Neuromusculoskeletal System0 aSoft Robots that Mimic the Neuromusculoskeletal System bSpringerc10/2016 a259-2630 vConverging Clinical and Engineering Research on Neurorehabilitation3 a

In motor control studies, the question on which
parameters human beings and animals control through their
nervous system has been extensively explored and discussed,
and several hypotheses proposed. It is widely acknowledged
that useful inputs in this problem could be provided by
developing artificial replication of the neuromusculoskeletal
system, to experiment different motor control hypothesis. In
this paper we present such device, which reproduces many of
the characteristics of an agonistic-antagonistic muscular pair
acting on a joint.

10aRobotics1 aGarabini, M.1 aDella Santina1 aBianchi, M.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. uhttp://link.springer.com/chapter/10.1007/978-3-319-46669-9_4501531nas a2200277 4500008004100000022002200041245007600063210006900139260003800208300001200246490000700258520073400265653001200999653001301011100001901024700001601043700001301059700002001072700001801092700001501110700001601125700001501141700001601156700001501172856006601187 2016 eng d a978-3-319-46668-200aThe SoftHand Pro: Translation from Robotic Hand to Prosthetic Prototype0 aSoftHand Pro Translation from Robotic Hand to Prosthetic Prototy bSpringer International Publishing a469-4730 v153 a

This work presents the translation from a humanoid robotic hand to a prosthetic prototype and its first evaluation in a set of 9 persons with amputation. The Pisa/IIT SoftHand is an underactuated hand built on the neuroscientific principle of motor synergies enabling it to perform natural, human-like movements and mold around grasped objects with minimal control input. These features motivated the development of the SoftHand Pro, a prosthetic version of the SoftHand built to interface with a prosthetic socket. The results of the preliminary testing of the SoftHand Pro showed it to be a highly functional design with an intuitive control system. Present results warrant further testing to develop the SoftHand Pro.

10aHaptics10aRobotics1 aGodfrey, S. B.1 aBianchi, M.1 aZhao, K.1 aCatalano, M. G.1 aBreighner, R.1 aTheuer, A.1 aAndrews, K.1 aGrioli, G.1 aSantello, M1 aBicchi, A. uhttp://link.springer.com/chapter/10.1007/978-3-319-46669-9_7801929nas a2200205 4500008003900000245012300039210006900162260003900231300001600270520124500286653001201531653001301543100001401556700001801570700002001588700001501608700001701623700001501640856006801655 2016 d00aSoftHand Pro-D: Matching Dynamic Content of Natural User Commands with Hand Embodiment for Enhanced Prosthesis Control0 aSoftHand ProD Matching Dynamic Content of Natural User Commands  aStockholm, Sweden, May 16-21bIEEE a3516 - 35233 a

State of the art of hand prosthetics is divided between simple and reliable gripper-like systems and sophisticate hi-tech poly-articular hands which tend to be complex both in their design and for the patient to operate. In this paper, we introduce the idea of decoding different movement intentions of the patient using the dynamic frequency content of the control signals in a natural way. We move a step further showing how this idea can be embedded in the mechanics of an underactuated soft hand by using only passive damping components.

In particular we devise a method to design the hand hardware to obtain a given desired motion. This method, that we call of the dynamic synergies, builds on the theory of linear descriptor systems, and is based on the division of the hand movement in a slow and a fast components. We use this method to evolve the design of the Pisa/IIT SoftHand in a prototype prosthesis which, while still having 19 degrees of freedom and just one motor, can move along two different synergistic directions of motion (and combinations of the two), to perform either a pinch or a power grasp. Preliminary experimental results are presented, demonstrating the effectiveness of the proposed design

10aHaptics10aRobotics1 aPiazza, C1 aDella Santina1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=748753201880nas a2200181 4500008004100000022002200041245005200063210005100115300001200166490004800178520128200226653001301508100001701521700001901538700002301557700001501580856010301595 2016 eng d a978-3-319-26705-000aTeleimpedance Control: Overview and application0 aTeleimpedance Control Overview and application a151-1690 vSpringer Series on Touch and Haptic Systems3 a

In previous chapters, human hand and arm kinematics have been analyzed through a synergstic approach and the underlying concepts were used to design robotic systems and devise simplified control algorithms. On the other hand, it is well-known that synergies can be studied also at a muscular level as a coordinated activation of multiple muscles acting as a single unit to generate different movements. As a result, muscular activations, quantified through Electromyography (EMG) signals can be then processed and used as direct inputs to external devices with a large number of DOFs. In this chapter, we present a minimalistic approach based on tele-impedance control, where EMGs from only one pair of antagonistic muscle pair are used to map the users postural and stiffness references to the synergy-driven anthropomorphic robotic hand, described in chapter 6. In this direction, we first provide an overview of the teleimpedance control concept which forms the basis for the development of the hand controller. Eventually, experimental results evaluate the effectiveness of the teleimpedance control concept in execution of the tasks which require significant dynamics variation or are executed in remote environments with dynamic uncertainties.

10aRobotics1 aAjoudani, A.1 aGodfrey, S. B.1 aTsagarakis, N., G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/teleimpedance-control-overview-and-application.html02077nas a2200253 4500008004100000022001400041245007300055210006900128260001200197300001200209490000600221520137200227653001201599653001301611100001801624700001601642700001701658700001501675700002001690700001401710700001601724700001501740856006801755 2016 eng d a1939-141200aThimbleSense: a fingertip-wearable tactile sensor for grasp analysis0 aThimbleSense a fingertipwearable tactile sensor for grasp analys c03/2016 a121-1330 v93 a

Accurate measurement of contact forces between hand and grasped objects is crucial to study sensorimotor control during grasp and manipulation. In this work we introduce ThimbleSense, a prototype of individual-digit wearable force/torque sensor based on the principle of intrinsic tactile sensing. By exploiting the integration of this approach with an active marker-based motion capture system, the proposed device simultaneously measures absolute position and orientation of the fingertip, which in turn yields measurements of contacts and force components expressed in a global reference frame. The main advantage of this approach with respect to more conventional solutions is its versatility. Specifically, ThimbleSense can be used to study grasping and manipulation of a wide variety of objects, while still retaining complete force/torque measurements. Nevertheless, validation of the proposed device is a necessary step before it can be used for experimental purposes. In this work we present the results of a series of experiments designed to validate the accuracy of ThimbleSense measurements and evaluate the effects of distortion of tactile afferent inputs caused by the device’s rigid shells on grasp forces.

10aHaptics10aRobotics1 aBattaglia, E.1 aBianchi, M.1 aAltobelli, A1 aGrioli, G.1 aCatalano, M. G.1 aSerio, A.1 aSantello, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=729470201511nas a2200193 4500008003900000245004800039210004800087260004100135520094000176653001301116100001401129700001801143700002101161700002001182700001501202700001701217700001501234856006801249 2016 d00aToward an Adaptive Foot for Natural Walking0 aToward an Adaptive Foot for Natural Walking aCancun, Mexico, November 15-17, 20163 a

Many walking robot presented in literature stand
on rigid flat feet, with a few notable exceptions that embed
flexibility in their feet to optimize the energetic cost of walking.
This paper proposes a novel adaptive robot foot design, whose
main goal is to ease the task of standing and walking on uneven
terrains. After explaining the rationale behind our design
approach, we present the design of the SoftFoot, a foot able
to comply with uneven terrains and to absorb shocks thanks to
its intrinsic adaptivity, while still being able to rigidly support
the stance, maintaining a rather extended contact surface,
and effectively enlarging the equivalent support polygon. The
paper introduces the robot design and prototype and presents
preliminary validation and comparison versus a rigid flat foot
with comparable footprint and sole.

10aRobotics1 aPiazza, C1 aDella Santina1 aGasparri, G., M.1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=780342301467nas a2200145 4500008003900000245011500039210006900154260004500223520092800268653001301196100001601209700001701225700001501242856006401257 2016 d00aToward whole-body loco-manipulation: Experimental results on multi-contact interaction with the Walk-Man robot0 aToward wholebody locomanipulation Experimental results on multic aDanjeon, Korea, October 10-14 2016bIEEE3 a

In this paper a quasi-static framework for optimally controlling the contact force distribution is experimentally verified with the full-size compliant humanoid robot Walk-Man. The proposed approach is general enough to cope with multi-contact scenarios, i.e. robot-environment interactions occurring on feet and hands, up to the more general case of whole-body loco-manipulation, in which the robot is in contact with the environment also with the internal limbs, with a consequent loss of contact force controllability. Experimental tests were conducted with the Walk-Man robot (i) standing on flat terrain, (ii) standing on uneven terrain and (iii) interacting with the environment with both feet and a hand touching a vertical wall. Moreover, the influence of unmodeled weight on the robot, and the combination with a higher priority Cartesian tasks are shown. Results are presented also in the attached video.

10aRobotics1 aFarnioli, E1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=775922502013nas a2200361 4500008004100000245006600041210006500107260001200172300001600184490000700200520103900207653001301246100001201259700001501271700001601286700001401302700001901316700001501335700001401350700002001364700001501384700002001399700001501419700001901434700002301453700001801476700001601494700002001510700001601530700001501546700002201561856006801583 2016 eng d00aVariable Stiffness Actuators: Review on Design and Components0 aVariable Stiffness Actuators Review on Design and Components c10/2016 a2418 - 24300 v213 a

Variable stiffness actuators (VSAs) are complex mechatronic devices that are developed to build passively compliant, robust, and dexterous robots. Numerous different hardware designs have been developed in the past two decades to address various demands on their functionality. This review paper gives a guide to the design process from the analysis of the desired tasks identifying the relevant attributes and their influence on the selection of different components such as motors, sensors, and springs. The influence on the performance of different principles to generate the passive compliance and the variation of the stiffness are investigated. Furthermore, the design contradictions during the engineering process are explained in order to find the best suiting solution for the given purpose. With this in mind, the topics of output power, potential energy capacity, stiffness range, efficiency, and accuracy are discussed. Finally, the dependencies of control, models, sensor setup, and sensor quality are addressed.

10aRobotics1 aWolf, S1 aGrioli, G.1 aEiberger, O1 aFriedl, W1 aGrebenstein, M1 aHoppner, H1 aBurdet, E1 aCaldwell, D. G.1 aCarloni, R1 aCatalano, M. G.1 aLefeber, D1 aStramigioli, S1 aTsagarakis, N., G.1 aDamme, Van, M1 aHam, Van, R1 aVanderborght, B1 aVisser, L C1 aBicchi, A.1 aAlbu-Schaeffer, A uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=733002501944nas a2200217 4500008003900000245008800039210006900127260004600196300001600242520124600258653001301504100001701517700001701534700002001551700001601571700001301587700002001600700001501620700002301635856006801658 2016 d00a WALK-MAN humanoid lower body design optimization for enhanced physical performance0 aWALKMAN humanoid lower body design optimization for enhanced phy aStockholm, Sweden, May 16-21, 2016 bIEEE a1817 - 18243 a
The deployment of robots to assist in environments hostile for humans during emergency scenarios require robots to demonstrate enhanced physical performance, that includes adequate power, adaptability and robustness to physical interactions and efficient operation. This work presents the design and development of the lower body of the new high performance humanoid WALK-MAN, a robot developed recently to assist in disaster response scenarios. The paper introduces the details of the WALK-MAN lower-body, highlighting the innovative design optimization features considered to maximize the leg performance. Starting from the general lower body specifications the objectives of the design and how they were addressed are introduced, including the selection of the leg kinematics, the arrangement of the actuators and their integration with the leg structure to maximize the range of motion, reduce the leg mass and inertia, and shape the leg mass distribution for better dynamic performance. Physical robustness is ensured with the integration of elastic transmission and impact energy absorbing covers. Experimental walking trials demonstrate the correct operation of the legs while executing a walking gait.
10aRobotics1 aNegrello, F.1 aGarabini, M.1 aCatalano, M. G.1 aKryczka, P.1 aChoi, W.1 aCaldwell, D. G.1 aBicchi, A.1 aTsagarakis, N., G. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=748732702024nas a2200181 4500008003900000245006600039210006200105260004600167520136700213653001201580653001301592100001601605700001801621700001701639700001501656700001501671856015601686 2016 d00aA Wearable Fabric-based Display for Haptic Multi-Cue Delivery0 aWearable Fabricbased Display for Haptic MultiCue Delivery aPhiladelphia, USA, April 8-11, 2016bIEEE3 a

Softness represents one of the most informative

haptic properties, which plays a fundamental role in both

everyday tasks and more complex procedures. Thus, it is not

surprising that much effort has been devoted to designing haptic

systems able to suitably reproduce this information. At the

same time, wearability has gained an increasing importance as

a novel paradigm to enable a more effective and naturalistic

human robot interaction. Capitalizing upon our previous works

on grounded softness devices, in this paper we present the

Wearable Fabric Yielding Display (W-FYD), a fabric-based

tactile display for multi-cue delivery that can be worn by

user’s finger. W-FYD enables to implement both passive and

active tactile exploration. Different levels of stiffness can be

reproduced by modulating the stretching state of a fabric

through two DC motors. An additional vertical degree of

freedom is implemented through a lifting mechanism, which

enables to convey softness stimuli to the user’s finger pad.

Furthermore, a sliding effect on the finger can be also induced.

Experiments with humans show the effectiveness of W-FYD for

haptic multi-cue delivery.

10aHaptics10aRobotics1 aBianchi, M.1 aBattaglia, E.1 aPoggiani, M.1 aCiotti, S.1 aBicchi, A. uhttp://ieeexplore.ieee.org/search/searchresult.jsp?queryText=A%20Wearable%20Fabric-based%20Display%20for%20Haptic%20Multi-Cue%20Delivery&newsearch=true04167nas a2200229 4500008004500000245007700045210006900122260003400191300001000225520347300235653001203708653001303720100001503733700002103748700001703769700001603786700001303802700001503815700002003830700001903850856006803869 2015 engldsh 00aCharacterization of Nonlinear Finger Pad Mechanics for Tactile Rendering0 aCharacterization of Nonlinear Finger Pad Mechanics for Tactile R aChicago, USA, 22-25 June 2015 a63-683 a

The computation of skin forces and deformations for tactile rendering requires an accurate model of the extremely nonlinear behavior of the skin. In this work, we investigate the characterization of fingermechanics with the goal of designing accurate nonlinear models for tactile rendering. First, we describe a measurement setup that enables the acquisition of contact force and contact area in the context of controlled finger indentation experiments. Second, we describe an optimization procedure that estimates the parameters of strain-limiting deformation models that match best the acquired data. We show that the acquisition setup allows the measurement of force and area information with high repeatability, and the estimation method reaches nonlinear models that match the measured data with high accuracy.

10aHaptics10aRobotics1 aMiguel, E.1 aD'Angelo, M., L.1 aCannella, F.1 aBianchi, M.1 aMemeo, M1 aBicchi, A.1 aCaldwell, D. G.1 aOtaduy, M., A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=717769202368nas a2200193 4500008003900000245017400039210006900213260004900282300001600331520145500347653001301802100001501815700001801830700001601848700002001864700001501884700001501899856026001914 2015 d00aDesign and Realization of the CUFF - Clenching Upper-Limb Force Feedback Wearable Device for Distributed Mechano-Tactile Stimulation of Normal and Tangential Skin Forces0 aDesign and Realization of the CUFF Clenching UpperLimb Force Fee aHamburg, Germany, 28 Sept - 2 Oct 2015bIEEE a1186 - 11933 a

Rendering forces to the user is one of the main goals of haptic technology. While most force-feedback interfaces are robotic manipulators, attached to a fixed frame and designed to exert forces on the users while being moved, more recent haptic research introduced two novel important ideas. On one side, cutaneous stimulation aims at rendering haptic stimuli at the level of the skin, with a distributed, rather than, concentrated approach. On the other side, wearable haptics focuses on highly portable and mobile devices, which can be carried and worn by the user as the haptic equivalent of an mp3 player. This paper presents a light and simple wearable device (CUFF) for the distributed mechano-tactile stimulation of the user’s arm skin with pressure and stretch cues, related to normal and tangential forces, respectively. The working principle and the mechanical and control implementation of the CUFF device are presented. Then, after a basic functional validation, a first application of the device is shown, where it is used to render the grasping force of a robotic hand (the Pisa/IIT SoftHand). Preliminary results show that the device is capable to deliver in a reliable manner grasping force information, thus eliciting a good softness discrimination in users and enhancing the overall grasping experience.

10aRobotics1 aCasini, S.1 aMorvidoni, M.1 aBianchi, M.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=7353520&newsearch=true&queryText=Design%20and%20Realization%20of%20the%20CUFF%20-%20Clenching%20Upper-Limb%20Force%20Feedback%20Wearable%20Device%20for%20Distributed%20Mechano-Tactile%20Stimulatio01545nas a2200193 4500008003900000245007300039210006900112260004500181300001400226520093500240653001201175653001301187100001801200700001501218700002001233700001501253700001501268856006801283 2015 d00aDexterity augmentation on a synergistic hand: the Pisa/IIT SoftHand+0 aDexterity augmentation on a synergistic hand the PisaIIT SoftHan aSeoul, Korea, November 3 - 5, 2015bIEEE a497 - 5033 a
Soft robotics and under-actuation were recently demonstrated as good approaches for the implementation of humanoid robotic hands. Nevertheless, it is often difficult to increase the number of degrees of actuation of heavily under-actuated hands without compromising their intrinsic simplicity. In this paper we analyze the Pisa/IIT SoftHand and its underlying logic of adaptive synergies, and propose a method to double its number of degree of actuation, with a very reduced impact on its mechanical complexity. This new design paradigm is based on constructive exploitation of friction phenomena.
Based on this method, a novel prototype of under-actuated robot hand with two degrees of actuation is proposed, named Pisa/IIT SoftHand+. A preliminary validation of the prototype follows, based on grasping and manipulation examples of some objects.
10aHaptics10aRobotics1 aDella Santina1 aGrioli, G.1 aCatalano, M. G.1 aBrando, A.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=736359501921nas a2200181 4500008003900000245007200039210006900111260004900180300001600229520133600245653001201581653001301593100001901606700001701625700001401642700001501656856006801671 2015 d00aEffect of Homogenous Object Stiffness on Tri-digit Grasp Properties0 aEffect of Homogenous Object Stiffness on Tridigit Grasp Properti a Milano, Italy, August 25th-29th, 2015bIEEE a6704 - 67073 a
This paper presents experimental findings on how humans modulate their muscle activity while grasping objects of varying levels of compliance. We hypothesize that one of the key abilities that allows humans to successfully cope with uncertainties while grasping compliant objects is the ability to modulate muscle activity to control both grasp force and stiffness in a way that is coherent with the task. To that end, subjects were recruited to perform a grasp and lift task with a tripod-grasp device with contact surfaces of variable compliance. Subjects performed the task under four different compliance conditions while surface EMG from the main finger flexor and extensor muscles was recorded along with force and torque data at the contact points. Significant increases in the extensor muscle (the antagonist in the task) and co-contraction levels were found with increasing compliance at the contact points. These results suggest that the motor system may employ a strategy of increasing cocontraction, and thereby stiffness, to counteract the decreased stability in grasping compliant objects. Future experiments will examine the extent to which this phenomenon is also related to specific task features, such as precision versus power grasp and object weight.
 
10aHaptics10aRobotics1 aGodfrey, S. B.1 aAltobelli, A1 aRossi, M.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=731993105694nas a2200193 4500008004500000245008600045210006900131260004300200300001200243520507000255653001205325653001305337100001405350700001705364700001905381700001705400700001505417856006805432 2015 engldsh 00aElectromyographic Mapping of Finger Stiffness in Tripod Grasp: a Proof of Concept0 aElectromyographic Mapping of Finger Stiffness in Tripod Grasp a  aSingapore, 11 – 14 August 2015bIEEE a181-1863 a

Effective execution of a manipulation task using prosthetic or robotic hands requires that the motion and the impedance profiles of the fingers be appropriately commanded. This, however, brings some design and control challenges regarding the individual planning and realization of the finger motion and stiffnesstrajectories. It appears that the central nervous system solves for this complexity in an effective and coordinated manner which has been well-recognized under the concept of hand synergies. While the exploitation of this concept in kinematic coordinates has lead to the development of several successful robotic designs and control strategies, its extension to dynamic coordinates, such as coordinated stiffening of the fingers, remains to be investigated. Indeed, in this study we provide preliminary evidence on the existence of such coordinated stiffening patterns in human fingers and establish initial steps towards a real-time and effective modelling of the finger stiffness in a tripod grasp. To achieve this goal, the endpoint stiffness of the thumb, index and middle fingers of five healthy subjects are experimentally identified and correlated with the electromyography (EMG) signals recorded from a dominant antagonistic pair of the forearm muscles. Our findings suggest that: i) the magnitude of thestiffness ellipses at the fingertips grows in a coordinated way, subsequent to the co-contraction of the forearm muscles; ii) the length of the ellipses' axes appears to have a nearly linear relationship with the co-contraction level of the antagonistic muscle pair.

10aHaptics10aRobotics1 aRossi, M.1 aAltobelli, A1 aGodfrey, S. B.1 aAjoudani, A.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=728119601827nas a2200193 4500008004100000022001400041245008300055210007100138300001600209490000700225520116900232653002101401653001301422100001601435700001901451700001901470700001501489856012901504 2015 eng d a0018-928600aEpsilon–optimal synthesis for vehicles with vertically bounded Field-Of-View0 aEpsilon–optimal synthesis for vehicles with vertically bounded F a1204 - 12180 v603 a

This paper presents a contribution to the problem of obtaining an optimal synthesis for shortest paths for a unicycle guided by an on–board limited Field Of–View (FOV) sensor, which must keep a given landmark in sight. Previous works on this subject have provided an optimal synthesis for the case in which the FOV is limited in the horizontal directions (H– FOV, i.e. left and right boundaries). In this paper we study the complementary case in which the FOV is limited only in the vertical direction (V–FOV, i.e. upper and lower boundaries). With respect to the H–FOV case, the vertical limitation is all but a simple extension. Indeed, not only the geometry of extremal arcs is different, but also a more complex structure of the synthesis is revealed by analysis. We will indeed show that there exist initial configurations for which the optimal path does not exist. In such cases, we provide an e–optimal path whose length approximates arbitrarily well any other shorter path. Finally, we provide a partition of the motion plane in regions such that the optimal or e–optimal path from each point in that region is univocally determined.

10aEmbedded Control10aRobotics1 aSalaris, P.1 aCristofaro, A.1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/epsilon%E2%80%93optimal-synthesis-vehicles-vertically-bounded-field-view.html00659nas a2200205 4500008003900000245006700039210006500106260004800171300001600219653001200235653001300247100001800260700001600278700002100294700001800315700001700333700002000350700001500370856006800385 2015 d00aA Finite Element Model of Tactile Flow for Softness Perception0 aFinite Element Model of Tactile Flow for Softness Perception aMilano, Italy, August 25th-29th, 2015bIEEE a2430 - 243310aHaptics10aRobotics1 aBattaglia, E.1 aBianchi, M.1 aD'Angelo, M., L.1 aD'Imperio, M.1 aCannella, F.1 aScilingo, E. P.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=731888400700nas a2200169 4500008003900000245007500039210006900114260006000183300001400243653001200257653001300269100001500282700001600297700001700313700001500330856018500345 2015 d00aGrasp Planning with Soft Hands using Bounding Box Object Decomposition0 aGrasp Planning with Soft Hands using Bounding Box Object Decompo aHamburg, Germany, September 28 - October 02, 2015bIEEE a518 - 52310aHaptics10aRobotics1 aBonilla, M1 aResasco, D.1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=7353421&queryText=Grasp%20Planning%20with%20Soft%20Hands%20using%20Bounding%20Box%20Object%20Decomposition&newsearch=true00657nas a2200169 4500008003900000245009800039210006900137260003600206300001600242653001300258100001700271700001600288700001400304700001700318700001500335856013700350 2015 d00aLow-cost, Fast and Accurate Reconstruction of Robotic and Human Postures via IMU Measurements0 aLowcost Fast and Accurate Reconstruction of Robotic and Human Po aSeattle, USA, 25 - 30 MaybIEEE a2728 - 273510aRobotics1 aSantaera, G.1 aLuberto, E.1 aSerio, A.1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/low-cost-fast-and-accurate-reconstruction-robotic-and-human-postures-imu-measurements00559nas a2200169 4500008004100000245009600041210006900137260001200206300001000218490000700228653001300235100001900248700001600267700002000283700001500303856007100318 2015 eng d00aA muscle-like recruitment actuator with modular redundant actuation units for soft robotics0 amusclelike recruitment actuator with modular redundant actuation c12/2015 a40-500 v7410aRobotics1 aMathijssen, G.1 aSchultz, J.1 aVanderborght, B1 aBicchi, A. uhttp://www.sciencedirect.com/science/article/pii/S092188901500138406962nas a2200181 4500008004500000245008700045210006900132260004000201300001000241520637400251653001206625653001306637100001606650700001706666700001406683700001506697856006806712 2015 engldsh 00aA Novel Tactile Display for Softness and Texture Rendering in Tele-Operation Tasks0 aNovel Tactile Display for Softness and Texture Rendering in Tele aChicago, USA, 22-25 June 2015bIEEE a49-563 a

Softness and texture high-frequency information represent fundamental haptic properties for every day life activities and environment tactual exploration. While several displays have been produced to convey either softness or high-frequency information, there is no or little evidence of systems that are able to reproduce both these properties in an integrated fashion. This aspect is especially crucial in medical tele-operated procedures, where roughness and stiffness of human tissues are both important to correctly identify given pathologies through palpation (e.g. in tele-dermatology). This work presents a fabric yielding display (FYD-pad), a fabric-based tactile display for softness and texture rendering. The system exploits the control of two motors to modify both the stretching state of the elastic fabric forsoftness rendering and to convey texture information on the basis of accelerometer-based data. At the same time, the measurement of the contact area can be used to control remote or virtual robots. In this paper, we discuss the architecture of FYD-pad and the techniques used for softness and texturereproduction as well as for synthesizing probe-surface interactions from real data. Tele-operationexamples and preliminary experiments with humans are reported, which show the effectiveness of the device in delivering both softness and texture information.

10aHaptics10aRobotics1 aBianchi, M.1 aPoggiani, M.1 aSerio, A.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=717769000620nas a2200157 4500008003900000245010700039210006900146260003000215300001600245653001200261653001300273100001600286700001700302700001500319856012800334 2015 d00aOptimal Contact Force Distribution for Compliant Humanoid Robots in Whole-Body Loco-Manipulation Tasks0 aOptimal Contact Force Distribution for Compliant Humanoid Robots aSeattle, USA, 25 - 30 May a5675 - 568110aHaptics10aRobotics1 aFarnioli, E1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-contact-force-distribution-compliant-humanoid-robots-whole-body-loco00746nas a2200205 4500008003900000245009100039210006900130260004800199653001300247100001900260700001500279700001700294700001700311700002000328700001500348700001500363700001500378700002000393856012700413 2015 d00aPotential merits for space robotics from novel concepts of actuation for soft robotics0 aPotential merits for space robotics from novel concepts of actua aNoordwijk, The Netherlands May 11-13, 201510aRobotics1 aMathijssen, G.1 aTerryn, S.1 aFunemont, R.1 aGarabini, M.1 aCatalano, M. G.1 aGrioli, G.1 aLefeber, D1 aBicchi, A.1 aVanderborght, B uhttp://www.centropiaggio.unipi.it/publications/potential-merits-space-robotics-novel-concepts-actuation-soft-robotics.html02477nas a2200181 4500008004500000245010600045210006900151260004900220300001600269520185200285653001202137653001302149100001702162700001302179700002002192700001502212856006802227 2015 engldsh 00aA Reduced-Complexity Description of Arm Endpoint Stiffness with Applications to Teleimpedance Control0 aReducedComplexity Description of Arm Endpoint Stiffness with App aHamburg, Germany, 28 Sept - 2 Oct 2015bIEEE a1017 - 10233 a

Effective and stable execution of a remote task in an uncertain environment requires that the task force and position trajectories of the slave robot be appropriately commanded. To achieve this goal, in teleimpedance control, a reference command which consists of the stiffness and position profiles of the master is computed and realized by the compliant slave robot in real-time. This highlights the need for a suitable and computationally efficient tracking of the human limb stiffness profile in real-time. In this direction, based on the observations in human neuromotor control which give evidence on the predominant use of the arm configuration in directional adjustments of the endpoint stiffness profile, and the role of muscular co-activations which contribute to a coordinated stiffening of the task stiffness in all directions, we propose a novel and computationally efficient model of the arm endpoint stiffness behaviour. With the purpose of real-time tracking of the human arm kinematics, an arm triangle is introduced using three body markers at the shoulder, elbow and wrist joints. In addition, a co-contraction index is defined using muscular activities of a dominant antagonistic muscle pair. Calibration and identification of the model parameters are carried out experimentally, using perturbation-based arm endpoint stiffness measurements in different arm configurations and co-contraction levels of the chosen muscles. Results of this study suggest that the proposed model enables the master to naturally execute a remote task by modulating the direction of the major axes of the endpoint stiffness and its volume using arm configuration and the co-ativation of the involved muscles, respectively.

10aHaptics10aRobotics1 aAjoudani, A.1 aFang, C.1 aTsagarakis, N G1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=735349500538nas a2200145 4500008003900000245007000039210006300109260003000172300001600202653001300218100001700231700002000248700001500268856010900283 2015 d00aOn the Role of Robot Configuration in Cartesian Stiffness Control0 aRole of Robot Configuration in Cartesian Stiffness Control aSeattle, USA, 25 - 30 May a1010 - 101610aRobotics1 aAjoudani, A.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/role-robot-configuration-cartesian-stiffness-control.html00609nas a2200157 4500008003900000245008500039210006900124260003600193300001600229653001300245100001500258700001600273700001900289700001500308856012800323 2015 d00aSample-Based Motion Planning for Robot Manipulators with Closed Kinematic Chains0 aSampleBased Motion Planning for Robot Manipulators with Closed K aSeattle, USA, 25 - 30 MaybIEEE a2522 - 252710aRobotics1 aBonilla, M1 aFarnioli, E1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/sample-based-motion-planning-robot-manipulators-closed-kinematic-chains.html02064nas a2200169 4500008004500000245009400045210006900139260004900208300001400257520140600271653001301677100001501690700001901705700002001724700001501744856013501759 2015 engldsh 00aA Selective Recruitment Strategy for Exploiting Muscle-Like Actuator Impedance Properties0 aSelective Recruitment Strategy for Exploiting MuscleLike Actuato aHamburg, Germany, 28 Sept - 2 Oct 2015bIEEE a2231-22373 a

Two leading qualities of skeletal muscle that produce good performance in uncertain environments are damage tolerance and the ability to modulate impedance. For this reason, robotics researchers are greatly interested in discovering the key characteristics of muscles that give them these properties and replicating them in actuators for robotic devices. This paper describes a method to harness the redundancy present in muscle-like actuation systems composed of multiple motor units and shows that they have these same two qualities. By carefully choosing which motor units are recruited, the impedance viewed from the environment can be modulated while maintaining the same overall activation level. The degree to which the impedance can be controlled varies with total activation level and actuator length.

Discretizing the actuation effort into multiple parts that work together, inspired by the way muscle fibers work in the human body, produces damage-tolerant behavior. This paper shows that this not only produces reasonably good resolutions without inordinate numbers of units, but gives the control system the ability to set the impedance along with the drive effort to the load.

10aRobotics1 aShultz, J.1 aMathijssen, G.1 aVanderborght, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/selective-recruitment-strategy-exploiting-muscle-actuator-impedance-properties.html01761nas a2200133 4500008004100000245004400041210004400085490000700129520135200136653001301488100001501501700001801516856009301534 2015 eng d00aSocial Robotics and Societies of Robots0 aSocial Robotics and Societies of Robots0 v313 a

The sustainability of social robotics and other ambitious research programs

depends on the identification of lines of research that are coherent with its

visionary goals while satisfying more stringent constraints of feasibility and near-
term pay-offs. These multiple constraints are naturally conducive to the idea of a

society of robots operating within the physical environments of everyday human

life, developing there rich robot-robot social exchanges, and yet refraining from

any physical contact with human beings.

Achieving the visionary goals of social robotics or its more realistic objectives

requires extensive multidisciplinary cooperation. Accordingly, social robotics

may come to play a significant coordinating role for the constellation of research

communities in robotics. This coordinating role is exemplified here by reference

to a principled approach to robotic hand control based on sensory-motor soft

synergies: pursued in some current investigations on artificial hands, this

approach promises to meet distinctive needs arising in social robotics in the way

of dexterous manipulation of objects that are primarily conceived for human use.

10aRobotics1 aBicchi, A.1 aTamburrini, G uhttp://www.centropiaggio.unipi.it/publications/social-robotics-and-societies-robots.html01963nas a2200169 4500008003900000245009100039210006900130260000900199300001400208520142300222653001301645100001501658700001701673700002001690700001501710856006801725 2015 d00aSoft Actuation in Cyclic Motions: Stiffness Profile Optimization for Energy Efficiency0 aSoft Actuation in Cyclic Motions Stiffness Profile Optimization  bIEEE a107 - 1133 a
In this paper, we investigate the role of variable stiffness in the reduction of the energy cost for mechanical systems that perform desired tasks. The objective is to assess the use of Variable Stiffness Actuation (VSA) by determining an optimal stiffness profile and the associated energy cost of performing a desired task. For the analysis we consider mechanical systems of n-Degrees of Freedom (DoF), using VSA. We find an analytical solution that expresses the optimal stiffness profile during the task as a function of joint trajectories. This stiffness profile can be either constant or variable in time, and it minimizes a cost function, when performing a desired task.
We calculate the cost related to the torque of the system and the additional cost of changing or keeping a stiffness actively constant. Additionally, we discuss some cases for which it is worth to change the stiffness during a task and cases for which a constant stiffness may be better solution. Furthermore, from simulations and experiments we show cases in which using a variable stiffness profile allows cost savings w.r.t. constant
stiffness. The use of variable stiffness depends on the task, i.e. on the joint trajectories and their frequency, as well as on the mechanical implementation of the actuator used.
10aRobotics1 aVelasco, A1 aGarabini, M.1 aCatalano, M. G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=736352200587nas a2200181 4500008004500000245009000045210006900135260004400204300001400248653001300262100001300275700001400288700001100302700001700313700001100330700001500341856004900356 2015 engldsh 00aTeaching by Demonstration on Dual-arm Robot using HRI Variable Stiffness Transferring0 aTeaching by Demonstration on Dualarm Robot using HRI Variable St aZhuhai, China, December 6-9, 2015bIEEE a1202-120810aRobotics1 aYang, C.1 aLiang, P.1 aLi, Z.1 aAjoudani, A.1 aSu, C.1 aBicchi, A. uhttp://ieeexplore.ieee.org/document/7418935/02901nas a2200205 4500008004100000245012300041210006900164260001200233300001000245490001400255520224500269653001302514100001502527700001702542700002002559700001402579700001502593700001602608856007102624 2015 eng d00aTele- Impedance based Assistive Control for a Compliant Knee Exoskeleton: Stiffness Augmentation and Motion Assistance0 aTele Impedance based Assistive Control for a Compliant Knee Exos c11/2015 a78-900 v73 part A3 a

This paper presents a tele-impedance based assistive control scheme for a knee exoskeleton device. The proposed controller captures the user’s intent to generate task-related assistive torques by means of the exoskeleton in different phases of the subject’s normal activity. To do so, a detailed musculoskeletal model of the human knee is developed and experimentally calibrated to best match the user’s kinematic and dynamic behavior. Three dominant antagonistic muscle pairs are used in our model, in which electromyography (EMG) signals are acquired, processed and used for the estimation of the knee joint torque, trajectory and the stiffness trend, in real time. The estimated stiffness trend is then scaled and mapped to a task-related stiffness interval to agree with the desired degree of assistance. The desired stiffness and equilibrium trajectories are then tracked by the exoskeleton’s impedance controller. As a consequence, while minimum muscular activity corresponds to low stiffness, i.e. highly transparent motion, higher co-contractions result in a stiffer joint and a greater level of assistance. To evaluate the robustness of the proposed technique, a study of the dynamics of the human–exoskeleton system is conducted, while the stability in the steady state and transient condition is investigated. In addition, experimental results of standing-up and sitting-down tasks are demonstrated to further investigate the capabilities of the controller. The results indicate that the compliant knee exoskeleton, incorporating the proposed tele-impedance controller, can effectively generate assistive actions that are volitionally and intuitively controlled by the user’s muscle activity.

 

10aRobotics1 aKaravas, N1 aAjoudani, A.1 aTsagarakis, N G1 aSaglia, J1 aBicchi, A.1 aCaldwell, D uhttp://www.sciencedirect.com/science/article/pii/S092188901400212700922nas a2200325 4500008004100000245006100041210005800102260001200160300001200172490000700184653001300191100001500204700001200219700001700231700002000248700001400268700002000282700001500302700001400317700001900331700001800350700001500368700001900383700002000402700001800422700002000440700002200460700001500482856009900497 2015 eng d00aVariable Stiffness Actuators: the user’s point of view0 aVariable Stiffness Actuators the user s point of view c05/2015 a727-7430 v3410aRobotics1 aGrioli, G.1 aWolf, S1 aGarabini, M.1 aCatalano, M. G.1 aBurdet, E1 aCaldwell, D. G.1 aCarloni, R1 aFriedl, W1 aGrebenstein, M1 aLaffranchi, M1 aLefeber, D1 aStramigioli, S1 aTsagarakis, N G1 aDamme, Van, M1 aVanderborght, B1 aAlbu-Schaeffer, A1 aBicchi, A. uhttp://ijr.sagepub.com/cgi/reprint/0278364914566515v1.pdf?ijkey=anmgudvoLz7ZloP&keytype=finite00620nas a2200193 4500008003900000245005500039210005500094260006000149300001600209653001300225100001800238700001700256700001900273700001600292700002000308700001500328700001500343856006800358 2015 d00aVariable Stiffness Control for Oscillation Damping0 aVariable Stiffness Control for Oscillation Damping aHamburg, Germany, September 28 - October 02, 2015bIEEE a6543 - 655010aRobotics1 aGasparri, G M1 aGarabini, M.1 aPallottino, L.1 aMalagia, L.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=735431200559nas a2200169 4500008003900000245005900039210005900098260002300157300001700180653001200197653001300209100001500222700001700237700001700254700001500271856010300286 2014 d00aActive gathering of frictional properties from objects0 aActive gathering of frictional properties from objects aChicago, USAbIEEE a3982 - 3987 10aHaptics10aRobotics1 aRosales, C1 aAjoudani, A.1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/active-gathering-frictional-properties-objects.html00630nas a2200193 4500008004100000245007500041210006900116300001400185490000700199653001200206653001300218100002000231700001500251700001600266700001400282700001400296700001500310856011100325 2014 eng d00aAdaptive Synergies for the Design and Control of the Pisa/IIT SoftHand0 aAdaptive Synergies for the Design and Control of the PisaIIT Sof a768–7820 v3310aHaptics10aRobotics1 aCatalano, M. G.1 aGrioli, G.1 aFarnioli, E1 aSerio, A.1 aPiazza, C1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-synergies-design-and-control-pisaiit-softhand.html00729nas a2200217 4500008004100000022001400041245008600055210006900141300001400210490000700224653001300231100001600244700001600260700001400276700001400290700001500304700001700319700001500336700002200351856013800373 2014 eng d a0178-231200aBiomechanisch sichere Geschwindigkeitsregelung fur die Mensch-Roboter Interaktion0 aBiomechanisch sichere Geschwindigkeitsregelung fur die MenschRob a175 - 1870 v6210aRobotics1 aHaddadin, S1 aHaddadin, S1 aKhoury, A1 aRokahr, T1 aParusel, S1 aBurgkart, R.1 aBicchi, A.1 aAlbu-Schaeffer, A uhttp://www.centropiaggio.unipi.it/publications/biomechanisch-sichere-geschwindigkeitsregelung-fur-die-mensch-roboter-interaktion.html00876nas a2200241 4500008003900000245009000039210006900129260005200198300001200250490008500262653001200347653001300359100001900372700001600391700001400407700001500421700001300436700001700449700001600466700001400482700001500496856012300511 2014 d00aA change in the fingertip contact area induces an illusory displacement of the finger0 achange in the fingertip contact area induces an illusory displac aVersailles, France), June 2014bSpringer-Verlag a72 - 790 vLNCS - Free Preview Haptics: Neuroscience, Devices, Modeling, and Applications10aHaptics10aRobotics1 aMoscatelli, A.1 aBianchi, M.1 aSerio, A.1 aAtassi, Al1 aFani, S.1 aTerekhov, A.1 aHayward, V.1 aErnst, M.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/change-fingertip-contact-area-induces-illusory-displacement-finger.html00737nas a2200217 4500008003900000245009400039210006900133260001600202300001500218653001200233653001300245100001600258700001600274700001400290700001400304700001300318700001700331700002000348700001500368856013600383 2014 d00aDesign and preliminary affective characterization of a novel fabric-based tactile display0 aDesign and preliminary affective characterization of a novel fab aHouston, TX a 591 - 59610aHaptics10aRobotics1 aBianchi, M.1 aValenza, G.1 aSerio, A.1 aLanata, A1 aGreco, L1 aNardelli, M.1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-and-preliminary-affective-characterization-novel-fabric-based-tactile-display02541nas a2200169 4500008003900000245006100039210006100100260002700161300001700188520198300205653001302188100001202201700001702213700001302230700001502243856011302258 2014 d00aDrum Stroke Variation Using Variable Stiffness Actuators0 aDrum Stroke Variation Using Variable Stiffness Actuators aChicago, IL, USAbIEEE a3892 - 3897 3 a

One interesting field of robotics technology is related to the entertainment industry. Performing a musical piece using a robot is a difficult task because music presents many features like melody, rhythm, tone, harmony and so on. Addressing these tasks with a robot is not trivial to implement. Most of approaches which related to this specific field lacks of quality to perform in front of human audience. Implementation of human-like motions can not be properly achieved with a conventional robot actuator. Consequently, we exploit a new type of actuator which simplifies the drawbacks of a conventional one. We used Variable Stiffness Actuator(VSA) instead of using conventional actuator. We can control position, force, and stiffness, simultaneously by using VSA. The most important novel feature is its controllable stiffness. When the stiffness of the actuator is changed, the characteristics of the actuator's response also changes. We implemented the specific stroke which is called “double strokeusing one of variable stiffness actuator. Although the double stroke is known as a special stroke which could be performed by human only, double stroke is successfully implemented by stiffness variation.

10aRobotics1 aKim, Y.1 aGarabini, M.1 aPark, J.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/drum-stroke-variation-using-variable-stiffness-actuators.html00725nas a2200193 4500008003900000245010500039210006900144260004000213653001200253653001300265100001600278700001800294700001800312700001600330700001500346700001700361700001700378856013600395 2014 d00aExploiting hand kinematic synergies and wearable under-sensing for hand functional grasp recognition0 aExploiting hand kinematic synergies and wearable undersensing fo aNovember 3–5, 2014 Athens, Greece10aHaptics10aRobotics1 aBianchi, M.1 aCarbonaro, N.1 aBattaglia, E.1 aLorussi, F.1 aBicchi, A.1 aDe Rossi, D.1 aTognetti, A. uhttp://www.centropiaggio.unipi.it/publications/exploiting-hand-kinematic-synergies-and-wearable-under-sensing-hand-functional-grasp00574nas a2200181 4500008003900000245005600039210005500095260001600150653001200166653001300178100001900191700001700210700001600227700002000243700001500263700001500278856009900293 2014 d00aExploring haptic feedback for the Pisa/IIT SoftHand0 aExploring haptic feedback for the PisaIIT SoftHand aHouston, TX10aHaptics10aRobotics1 aGodfrey, S. B.1 aAjoudani, A.1 aBianchi, M.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/exploring-haptic-feedback-pisaiit-softhand.html00647nas a2200205 4500008004100000245009600041210006900137300001400206490000600220653001200226653001300238100001700251700001900268700002000287700001600307700001500323700002000338700001500358856006800373 2014 eng d00aExploring Teleimpedance and Tactile Feedback for Intuitive Control of the Pisa/IIT SoftHand0 aExploring Teleimpedance and Tactile Feedback for Intuitive Contr a203 - 2150 v710aHaptics10aRobotics1 aAjoudani, A.1 aGodfrey, S. B.1 aCatalano, M. G.1 aBianchi, M.1 aGrioli, G.1 aTsagarakis, N G1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=675555401675nas a2200205 4500008004100000022002200041245005100063210004800114260002000162300001400182490004800196520106700244653001201311653001301323100001601336700001401352700002001366700001501386856006801401 2014 eng d a978-1-4471-6532-300aA Fabric-based Approach for Softness Rendering0 aFabricbased Approach for Softness Rendering bSpringer-Verlag a219 - 2400 vSpringer Series on Touch and Haptic Systems3 a

In this chapter we describe a softness display based on the contact area spread rate (CASR) paradigm. This device uses a stretchable fabric as a substrate that can be touched by users, while contact area is directly measured via an optical system. By varying the stretching state of the fabric, different stiffness values can be conveyed to users. We describe a first technological implementation of the display and compare its performance in rendering various levels of stiffness with the one exhibited by a pneumatic CASR-based device. Psychophysical experiments are reported and discussed. Afterwards, we present a new technological implementation for the fabric-based display, with reduced dimensions and faster actuation, which enables rapid changes in the fabric stretching state. These changes are mandatory to properly track typical force/area curves of real materials. System performance in mimicking force-area curves obtained from real objects exhibits a high degree of reliability, also in eliciting overall discriminable levels of softness.

10aHaptics10aRobotics1 aBianchi, M.1 aSerio, A.1 aScilingo, E. P.1 aBicchi, A. uhttp://link.springer.com/chapter/10.1007%2F978-1-4471-6533-0_1102519nas a2200229 4500008003900000245002900039210002900068260003600097300001400133520187600147653001202023653001302035100001502048700001602063700001402079700002002093700001502113700001702128700001702145700001502162856011202177 2014 d00aGrasping with Soft Hands0 aGrasping with Soft Hands aMadrid, Spain, November 18 - 20 a581 - 5873 a

Despite some prematurely optimistic claims, the ability of robots to grasp general objects in unstructured environments still remains far behind that of humans. This is not solely caused by differences in the mechanics of hands: indeed, we show that human use of a simple robot hand (the Pisa/IIT SoftHand) can afford capabilities that are comparable to natural grasping. It is through the observation of such human-directed robot hand operations that we realized how fundamental in everyday grasping and manipulation is the role of hand compliance, which is used to adapt to the shape of surrounding objects. Objects and environmental constraints are in turn used to functionally shape the hand, going beyond its nominal kinematic limits by exploiting structural softness. In this paper, we set out to study grasp planning for hands that are simple — in the sense of low number of actuated degrees of freedom (one for the Pisa/IIT SoftHand) — but are soft, i.e. continuously deformable in an infinity of possible shapes through interaction with objects. After general considerations on the change of paradigm in grasp planning that this setting brings about with respect to classical rigid multi-dof grasp planning, we present a procedure to extract grasp affordances for the Pisa/IIT SoftHand through physically accurate numerical simulations. The selected grasps are then successfully tested in an experimental scenario.

10aHaptics10aRobotics1 aBonilla, M1 aFarnioli, E1 aPiazza, C1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=7041421&queryText%3DGrasping+with+Soft+Hands01918nas a2200265 4500008004100000245008800041210006900129300001200198490000700210520109000217653001201307653001301319100001701332700001501349700001601364700002001380700001401400700001601414700001701430700001501447700001801462700002001480700002001500856013201520 2014 eng d00aHANDS.DVI: A DeVice-Independent programming and control framework for robotic HANDS0 aHANDSDVI A DeViceIndependent programming and control framework f a197-2150 v943 a

The scientific goal of HANDS.DVI consists of developing a common
framework to programming robotic hands independently from their kinematics,
mechanical construction, and sensor equipment complexity. Recent results on the
organization of the human hand in grasping and manipulation are the inspiration
for this experiment. The reduced set of parameters that we effectively use to control
our hands is known in the literature as the set of synergies. The synergistic
organization of the human hand is the theoretical foundation of the innovative approach
to design a unified framework for robotic hands control. Theoretical tools
have been studied to design a suitable mapping function of the control action (decomposed
in its elemental action) from a human hand model domain onto the
articulated robotic hand co-domain. The developed control framework has been
applied on an experimental set up consisting of two robotic hands with dissimilar
kinematics grasping an object instrumented with force sensors.

10aHaptics10aRobotics1 aSalvietti, G1 aGioioso, G1 aMalvezzi, M1 aPrattichizzo, D1 aSerio, A.1 aFarnioli, E1 aGabiccini, M1 aBicchi, A.1 aSarakoglou, I1 aTsagarakis, N G1 aCaldwell, D. G. uhttp://www.centropiaggio.unipi.it/publications/handsdvi-device-independent-programming-and-control-framework-robotic-hands.html00533nas a2200169 4500008003900000245006400039210006400103260002600167300001600193653001200209653001300221100002100234700001800255700001500273700002000288856005500308 2014 d00aHaptic Exploration of Unknown Surfaces with Discontinuities0 aHaptic Exploration of Unknown Surfaces with Discontinuities aChicago, USAc09/2014 a1255 - 126010aHaptics10aRobotics1 aJamisola, R., S.1 aKormushev, P.1 aBicchi, A.1 aCaldwell, D. G. uhttp://kormushev.com/papers/Jamisola_IROS-2014.pdf02577nas a2200241 4500008003900000245009300039210006900132260004200201300001400243520183800257653001202095653001302107100001702120700001102137700001402148700001602162700001902178700001502197700002002212700001502232700002002247856006802267 2014 d00aManipulation Framework for Compliant Humanoid COMAN: Application to a Valve Turning Task0 aManipulation Framework for Compliant Humanoid COMAN Application  aMadrid, Spain, November 18 - 20bIEEE a664 - 6703 a

With the purpose of achieving a desired interaction performance for our compliant humanoid robot (COMAN), in this paper we propose a semi-autonomous control framework and evaluate it experimentally in a valve turning setup. The control structure consists of various modules and interfaces to identify the valve, locate the robot in front of it and perform the manipulation. The manipulation module implements four motion primitives (Reach, Grasp, Rotate and Disengage) and realizes the corresponding desired impedance profile for each phase to accomplish the task. In this direction, to establish a stable and compliant contact between the valve and the robot hands, while being able to generate the sufficient rotational torques depending on the valve's friction, Rotate incorporates a novel dual-arm impedance control technique to plan and realize a task-appropriate impedance profile. Results of the implementation of the proposed control framework are firstly evaluated in simulation studies using Gazebo. Subsequent experimental results highlight the efficiency of the proposed impedance planning and control in generation of the required interaction forces to accomplish the task.

10aHaptics10aRobotics1 aAjoudani, A.1 aLee, J1 aRocchi, A1 aFerrati, M.1 aHoffman, Mingo1 aSettimi, A1 aCaldwell, D. G.1 aBicchi, A.1 aTsagarakis, N G uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=704143400719nas a2200205 4500008003900000245009500039210006900134260002300203653001300226100001500239700001400254700001900268700001600287700001400303700001400317700001300331700002000344700001500364856013400379 2014 d00aA modular approach for remote operation of humanoid robots in search and rescue scenarios 0 amodular approach for remote operation of humanoid robots in sear aRome, 5-6 May 201410aRobotics1 aSettimi, A1 aPavan, C.1 aVarricchio, V.1 aFerrati, M.1 aMingo, E.1 aRocchi, A1 aMelo, K.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/modular-approach-remote-operation-humanoid-robots-search-and-rescue-scenarios.html02710nas a2200193 4500008003900000245011400039210007100153260004700224300001600271520205600287653001202343653001302355100001702368700002002385700001102405700001702416700001502433856006802448 2014 d00aNatural Redundancy Resolution in Dual-Arm Manipulation using Configuration Dependent Stiffness (CDS) Control0 aNatural Redundancy Resolution in DualArm Manipulation using Confi aHong Kong, May 31 2014-June 7 2014 bIEEE a1480 - 14863 a

Incorporation of human motor control principles in the motion control architectures for humanoid robots or assistive and prosthesis devices will permit these systems not only to look anthropomorphic and natural at the body ware level but also to generate natural motion profiles resembling those executed by humans during manipulation and locomotion. In this work, relying on the observations on human bimanual coordination, a novel realtime motion control strategy is proposed to regulate the desired Cartesian stiffness profile during the execution of bimanual tasks. The novelty of the proposed control scheme relies on the use of common mode stiffness (CMS) and configuration dependent stiffness (CDS) to regulate the size and directionality of the task space stiffness ellipsoid. Thanks to the CDS control, the proposed scheme is not only proved to be effective in regulating the desired stiffness ellipsoid but also permits to resolve the manipulator redundancy in a natural manner. The effectiveness of the controller is evaluated in an experimental setup in which two cooperating robotic arms are executing an assembly task. Experimental results demonstrate that the proposed dual-arm CDS-CMS controller is effective in tracking the desired stiffness ellipsoids as well as in producing human-like natural motions for the two robotic arms.

10aHaptics10aRobotics1 aAjoudani, A.1 aTsagarakis, N G1 aLee, J1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=694525200594nas a2200169 4500008003900000245006300039210006100102260004200163653001300205100001300218700001700231700001500248700002000263700001600283700001500299856011000314 2014 d00aOpen Source VSA-CubeBots for Rapid Soft Robot Prototyping 0 aOpen Source VSACubeBots for Rapid Soft Robot Prototyping a July 12, 2014, Berkeley, California 10aRobotics1 aMelo, K.1 aGarabini, M.1 aGrioli, G.1 aCatalano, M. G.1 aMalagia, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/open-source-vsa-cubebots-rapid-soft-robot-prototyping.html02223nas a2200217 4500008003900000245007700039210006900116260001700185300001600202520152500218653001201743653001301755100001401768700001701782700001701799700001801816700001701834700002001851700001501871856011901886 2014 d00aThe Patched Intrinsic Tactile Object: a Tool to Investigate Human Grasps0 aPatched Intrinsic Tactile Object a Tool to Investigate Human Gra aChicago, USA a1261 - 12683 a

In this paper we report on the development of a modular multi-DoF F/T sensor and its use in the implementation of a sensorized object capable of multi-touch detection. The sensor is composed of six 6-axis F/T sensors spatially organized on the faces of a cube. Different calibration methods are presented to directly tackle the coupling phenomena inherent to the spatial organization of the faces and the lightweight construction of the sensor which would have, otherwise, degraded its accuracy. To assess the performances of the calibration methods, a comparison is reported with respect to the measurements obtained with a commercial force/torque sensor considered as ground truth (ATI Delta). Thanks to the modular design and the possibility to cover the sensitive faces with surface patches of different geometry, a variety of sensorized objects with different shapes can be realized. The peculiar feature that all the components of the contact wrench can be measured on each face with high accuracy, renders it a unique tool in the study of grasp force distribution in humans, with envisioned use both in neuroscience investigations and robotic applications.

10aHaptics10aRobotics1 aSerio, A.1 aRiccomini, E1 aTartaglia, V1 aSarakoglou, I1 aGabiccini, M1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/patched-intrinsic-tactile-object-tool-investigate-human-grasps.html01066nas a2200361 4500008004100000245008500041210006900126260001200195300001100207490000600218653001300224100001900237700001900256700001700275700001700292700001700309700001500326700001500341700001700356700001400373700001800387700001500405700001800420700001900438700001700457700001300474700001500487700001700502700002100519700001300540700001500553856013600568 2014 eng d00aPeripheral Machine Interfaces: going beyond traditional surface electromyography0 aPeripheral Machine Interfaces going beyond traditional surface e c08/2014 a1 - 170 v810aRobotics1 aCastellini, C.1 aArtemiadis, P.1 aWininger, M.1 aAjoudani, A.1 aAlimusaj, M.1 aBicchi, A.1 aCaputo, B.1 aCraelius, W.1 aDosen, S.1 aEnglehart, K.1 aFarina, D.1 aGijsberts, A.1 aGodfrey, S. B.1 aHargrove, L.1 aIson, M.1 aKuiken, T.1 aMarkovic, M.1 aPilarski, P., M.1 aRupp, R.1 aScheme, E. uhttp://www.centropiaggio.unipi.it/publications/peripheral-machine-interfaces-going-beyond-traditional-surface-electromyography.html00502nas a2200145 4500008004100000245006300041210006300104653001200167653001300179100001500192700001500207700001600222700001300238856010500251 2014 eng d00aSpecial Issue on the Mechanics and Design of Robotic Hands0 aSpecial Issue on the Mechanics and Design of Robotic Hands10aHaptics10aRobotics1 aDollar, A.1 aBicchi, A.1 aCutkosky, M1 aHowe, D. uhttp://www.centropiaggio.unipi.it/publications/special-issue-mechanics-and-design-robotic-hands.html01934nas a2200169 4500008004100000022001400041245009100055210007100146300001700217490000700234520133800241653001301579100001401592700001501606700001501621856012801636 2014 eng d a1552-309800aA Stiffness Estimator for Agonistic–Antagonistic Variable-Stiffness-Actuator Devices0 aStiffness Estimator for Agonistic–Antagonistic VariableStiffness a1269 - 1278 0 v303 a

Safe physical human-robot interaction, conservation of energy, and adaptability are the main robotic applications that prompted the development of a number of variable stiffness actuators (VSAs). Implemented in a variety of ways, they use various technologies and feature the most diverse mechanical solutions, all of which share a fundamentally unavoidable nonlinear behavior. The control schemes proposed for these actuators typically aim at independent control of the position of the link and its stiffness. Although effective feedback control schemes using position and force sensors are commonplace in robotics, control of stiffness is at present completely open loop: The stiffness is inferred from the mathematical model of the actuator. We consider here the problem of estimating the nonlinear stiffness of VSA in agonistic-antagonistic configuration. We propose an algorithm based on modulating functions that allow us to avoid the need for numerical derivative and for which the tuning is then very simple. An analysis of the error demonstrates the convergence. Simulations are provided, and the algorithm is validated on experimental data.

10aRobotics1 aMenard, T1 aGrioli, G.1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6860244&queryText%3DA+stiffness+estimator+for+AA-VSA+devices00416nas a2200157 4500008003900000245002400039210002000063260001600083653001200099653001300111100001400124700001600138700001700154700001500171856007200186 2014 d00aThe tactile toolbox0 atactile toolbox aHouston, TX10aHaptics10aRobotics1 aSerio, A.1 aBianchi, M.1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tactile-toolbox.html00659nas a2200193 4500008003900000245007900039210006900118260001600187653001200203653001300215100001800228700001500246700002000261700001600281700001400297700001600311700001500327856012300342 2014 d00aThimbleSense: A new wearable tactile device for human and robotic fingers 0 aThimbleSense A new wearable tactile device for human and robotic aHouston, TX10aHaptics10aRobotics1 aBattaglia, E.1 aGrioli, G.1 aCatalano, M. G.1 aBianchi, M.1 aSerio, A.1 aSantello, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/thimblesense-new-wearable-tactile-device-human-and-robotic-fingers.html01920nas a2200193 4500008003900000245009300039210006900132260004400201300001700245520128700262653001201549653001301561100001801574700001501592700002001607700001601627700001501643856006801658 2014 d00aThimbleSense: An Individual-Digit Wearable Tactile Sensor for Experimental Grasp Studies0 aThimbleSense An IndividualDigit Wearable Tactile Sensor for Expe a Hong Kong, May 31 - June 7, 2014bIEEE a2728 - 2735 3 a

Measuring contact forces applied by a hand to a grasped object is a necessary step to understand the mysteries that still hide in the unparalleled human grasping ability. Nevertheless, simultaneous collection of information about the position of contacts and about the magnitude and direction of forces is still an elusive task. In this paper we introduce a wearable device that addresses this problem, and can be used to measure generalized forces during grasping. By assembling two supports around a commercial 6-axis force/torque sensor we obtain a thimble that can be easily positioned on a fingertip. The device is used in conjunction with an active marker-based motion capture system to simultaneously obtain absolute position and orientation of the thimbles, without requiring any assumptions on the kinematics of the hand. Finally, using the contact centroid algorithm, introduced in [1], position of contact points during grasping are determined. This paper shows the design and implementation of the device, as well as some preliminary experimental validation.

10aHaptics10aRobotics1 aBattaglia, E.1 aGrioli, G.1 aCatalano, M. G.1 aSantello, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=690725001589nas a2200205 4500008003900000245011500039210006900154260004300223300001400266520091400280653001201194653001301206100001701219700001601236700001401252700001701266700001701283700001501300856006801315 2014 d00a Three-digit grasp haptic device with variable contact stiffness for rehabilitation and human grasping studies0 aThreedigit grasp haptic device with variable contact stiffness f aPalermo, Italy, 16-19 June 2014 bIEEE a346 - 3503 a

This paper describes an haptic system designed to vary the stiffness of three contact points in an independent and controllable fashion, by suitably regulating the inner pressure of three pneumatic tactile displays. At the same time, the contact forces exerted by the user are measured by six degree-of-freedom force sensors placed under each finger. This device might be profitably used in hand rehabilitation and human grasping studies. We report and discuss preliminary results on device validation as well as some illustrative measurement examples.

10aHaptics10aRobotics1 aAltobelli, A1 aBianchi, M.1 aSerio, A.1 aBaud-Bovy, G1 aGabiccini, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=696139502070nas a2200205 4500008003900000020002200039245009600061210006900157260004300226300001600269520139100285653002101676653001301697100001901710700001601729700001901745700001701764700001501781856006801796 2014 d a978-1-4799-7746-800aOn Time-Optimal Trajectories for Differential Drive Vehicles with Field-Of-View Constraints0 aTimeOptimal Trajectories for Differential Drive Vehicles with Fi aLos Angeles, USA, December 15-17bIEEE a2191 - 21973 a

This paper presents the first step toward the study of minimum time trajectories for a differential drive robot, which is equipped with a fixed and limited Field-Of-View (FOV) camera, towards a desired configuration while keeping a given landmark in sight during maneuvers. While several previous works have provided a complete synthesis of shortest paths in case of both nonholonomic and FOV constraints, to the best of our knowledge, this paper represents the first analysis of minimum time trajectories with the two constraints. After showing the extremals of the problem at hand, i.e. straight lines, rotations on the spot, logarithmic spirals and involute of circles, we provide the optimal control laws that steer the vehicle along the path and the cost in terms of time along each extremal. Moreover, we compare some concatenations of extremals in order to reduce the complexity of the problem toward the definition of a sufficient finite set of optimal maneuvers.

10aEmbedded Control10aRobotics1 aCristofaro, A.1 aSalaris, P.1 aPallottino, L.1 aGiannoni, F.1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=703972302368nas a2200229 4500008003900000245009500039210006900134260004200203300001400245520165100259653001301910100001101923700001701934700001901951700001401970700001501984700001601999700001502015700002002030700002002050856006802070 2014 d00aUpper-body Impedance Control with an Intuitive Stiffness Emulation for a Door Opening Task0 aUpperbody Impedance Control with an Intuitive Stiffness Emulatio aMadrid, Spain, November 18 - 20bIEEE a713 - 7193 a

The advent of humanoids has brought new challenges in the real-world application. As a part of ongoing efforts to foster functionality of the robot accommodating a real environment, this paper introduces a recent progress on a door opening task with our compliant humanoid, CoMan. We presents a task-prioritized impedance control framework for an upper body system that includes a dual-arm, a waist, two soft hands, and 3D camera. Aimed to create desired responses to open the door, a novel stiffness modulation method is proposed, incorporating a realtime optimization. As a preliminary experiment, a full door-opening scenario (approaching to the door and reaching, grasping, rotating and pulling the door handle) is demonstrated under a semi-autonomous operation with a pilot. The experimental result shows the effectiveness and efficacy of the proposed impedance control approach. Despite of uncertainties from sensory data, the door opening task is successfully achieved and safe and robust interaction is established without creating excessive forces.

10aRobotics1 aLee, J1 aAjoudani, A.1 aHoffman, Mingo1 aRocchi, A1 aSettimi, A1 aFerrati, M.1 aBicchi, A.1 aTsagarakis, N G1 aCaldwell, D. G. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=704144101718nas a2200241 4500008003900000245009900039210006900138260004500207300001600252520097600268653001201244653001301256100001201269700001601281700001501297700001501312700002001327700001501347700001301362700001801375700001501393856006801408 2014 d00aVelvet Fingers: Grasp Planning and Execution for an Underactuated Gripper with Active Surfaces0 aVelvet Fingers Grasp Planning and Execution for an Underactuated aHong Kong, May 31 2014-June 7 2014bIEEE a3669 - 36753 a

In this work we tackle the problem of planning grasps for an underactuated gripper which enable it to retrieve target objects from a cluttered environment. Furthermore, we investigate how additional manipulation capabilities of the gripping device, provided by active surfaces on the inside of the fingers, can lead to performance improvement in the grasp execution process. To this end, we employ a simple strategy, in which the target object is `pulled-in' towards the palm during grasping which results in firm enveloping grasps. We show the effectiveness of the suggested methods by means of experiments conducted in a real-world scenario.

10aHaptics10aRobotics1 aKrug, R1 aStoyanov, T1 aBonilla, M1 aTincani, V1 aVaskeviciusz, N1 aFantoni, G1 aBirkz, A1 aLilienthal, A1 aBicchi, A. uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=690739000632nas a2200217 4500008003900000245004400039210004400083260003100127653001300158100001300171700001800184700001400202700001600216700001500232700001400247700001400261700001500275700001200290700002000302856009200322 2014 d00aYarp Based Plugins for Gazebo Simulator0 aYarp Based Plugins for Gazebo Simulator aRoma, Italy, 5 -6 May 201410aRobotics1 aMingo, E1 aTraversaro, S1 aRocchi, A1 aFerrati, M.1 aSettimi, A1 aRomano, F1 aNatale, L1 aBicchi, A.1 aNori, F1 aTsagarakis, N G uhttp://www.centropiaggio.unipi.it/publications/yarp-based-plugins-gazebo-simulator.html01494nas a2200157 4500008004100000245013500041210006900176490000700245520081600252653001301068100002001081700001501101700001801116700001501134856018701149 2013 eng d00aA Complete Observability Analysis of the Planar Bearing Localization and Mapping for Visual Servoing with Known Camera Velocities0 aComplete Observability Analysis of the Planar Bearing Localizati0 v103 a

This paper presents an analysis of planar bearing localization and mapping for visual servoing with known camera velocities. In particular, we investigate what is the subset of camera locations and environmental features that can be retrieved from dynamic observations obtained by a planar bearing sensor (nearly e.g., a pinhole camera). Results assume that the camera’s linear and angular velocities are available, which is equivalent to consider a unicycle vehicle carrying an onboard camera. Results hold if other system inputs are considered, e.g., an omnidirectional vehicle. The theoretical results may guide the design of nonlinear observers to estimate the variables of interest in real time to be applied to visual servoing schemes. An example of such an observer is discussed and simulated.

10aRobotics1 aBelo, F., A. W.1 aSalaris, P1 aFontanelli, D1 aBicchi, A. uhttp://www.intechopen.com/books/international_journal_of_advanced_robotic_systems/a-complete-observability-analysis-of-the-planar-bearing-localization-and-mapping-for-visual-servoing01630nas a2200205 4500008004100000245008400041210006900125260003100194300001600225520091300241653001301154100001501167700001501182700002001197700001501217700001701232700001501249700001501264856014501279 2013 eng d00aControlling the active surfaces of the Velvet Fingers: sticky to slippy fingers0 aControlling the active surfaces of the Velvet Fingers sticky to  aTokyo, JapancNovember 3-7 a5494 - 54993 a

Industrial grippers are often used for grasping, while in-hand re-orientation and positioning are dealt with by other means. Contact surface engineering has been recently proposed as a possible mean to introduce dexterity in simple grippers, as in the Velvet Fingers smart gripper, a novel concept of end-effector combining simple under-actuated mechanics and high manipulation possibilities, thanks to conveyors which are built in the finger pads. This paper undergoes the modeling and control of the active conveyors of the Velvet Fingers gripper which are rendered able to emulate different levels of friction and to apply tangential thrusts to the contacted objects. Through the paper particular attention is dedicated to the mechanical implementation, sense drive and control electronics of the device. The capabilities of the prototype are showed in some grasping and manipulation experiments.

10aRobotics1 aTincani, V1 aGrioli, G.1 aCatalano, M. G.1 aBonilla, M1 aGarabini, M.1 aFantoni, G1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6697152&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D669715200623nas a2200145 4500008004100000245013400041210006900175260003100244300001700275653001300292100001400305700001600319700001500335856012700350 2013 eng d00aA Device for Mimicking the Contact Force/Contact Area Relationship of Different Materials with Applications to Softness Rendering0 aDevice for Mimicking the Contact ForceContact Area Relationship  aTokyo, JapancNovember 3-7 a4484 - 4490 10aRobotics1 aSerio, A.1 aBianchi, M.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/device-mimicking-contact-forcecontact-area-relationship-different-materials00574nas a2200169 4500008004100000245006900041210006900110260001200179300001600191490000700207653001200214653001300226100001700239700001600256700001500272856011700287 2013 eng d00aGrasp Analysis Tools for Synergistic Underactuated Robotic Hands0 aGrasp Analysis Tools for Synergistic Underactuated Robotic Hands c11/2013 a1553 - 15760 v3210aHaptics10aRobotics1 aGabiccini, M1 aFarnioli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/grasp-analysis-tools-synergistic-underactuated-robotic-hands.html00604nas a2200157 4500008004100000245008500041210006900126260003100195300001500226653001300241100001600254700001700270700001500287700001500302856012900317 2013 eng d00aGrasp Compliance Regulation in Synergistically Controlled Robotic Hands with VSA0 aGrasp Compliance Regulation in Synergistically Controlled Roboti aTokyo, JapancNovember 3-7 a3015 -302210aRobotics1 aFarnioli, E1 aGabiccini, M1 aBonilla, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/grasp-compliance-regulation-synergistically-controlled-robotic-hands-vsa.html00579nas a2200145 4500008004100000245009100041210006900132300001600201653001300217100001700230700001700247700002000264700001500284856013400299 2013 eng d00aHuman-Like Impedance and Minimum Effort Control for Natural and Efficient Manipulation0 aHumanLike Impedance and Minimum Effort Control for Natural and E a4499 - 450510aRobotics1 aAjoudani, A.1 aGabiccini, M1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/human-impedance-and-minimum-effort-control-natural-and-efficient-manipulation.html00582nas a2200193 4500008004100000245009500041210006900136300001600205653001200221653001300233100001500246700001500261700002000276700001700296700001400313700001500327700001500342856003100357 2013 eng d00aImplementation and Control of the Velvet Fingers: a Dexterous Gripper with Active Surfaces0 aImplementation and Control of the Velvet Fingers a Dexterous Gri a2744 - 275010aHaptics10aRobotics1 aTincani, V1 aGrioli, G.1 aCatalano, M. G.1 aGarabini, M.1 aGrechi, S1 aFantoni, G1 aBicchi, A. u10.1109/ICRA.2013.6630955 02749nas a2200193 4500008004100000245009800041210006900139260001200208300001700220490000700237520208200244653001202326653001302338100002002351700001602371700001702387700001502404856013602419 2013 eng d00aOn Motion and Force Controllability of Precision Grasps with Hands Actuated by Soft Synergies0 aMotion and Force Controllability of Precision Grasps with Hands  c12/2013 a1440 - 1456 0 v293 a

To adapt to many different objects and tasks, hands are very complex systems with many degrees of freedom (DoFs), sensors, and actuators. In robotics, such complexity comes at the cost of size and weight of the hardware of devices, but it strongly affects also the ease of their programming. A possible approach to simplification consists in coupling some of the DOFs, thus affording a reduction of the number of effective inputs, and eventually leading to more efficient, simpler, and reliable designs. Such coupling can be at the software level, to achieve faster, more intuitive programmability or at the hardware level, through either rigid or compliant physical couplings between joints. Physical coupling between actuators and simplification of control through the reduction of independent inputs is also an often-reported interpretation of human hand movement data, where studies have demonstrated that few “postural synergies” explain most of the variance in hand configurations used to grasp different objects. Together with beneficial simplifications, the reduction of the number of independent inputs to a few coupled motions or “synergies” has also an impact on the ability of the hand to dexterously control grasp forces and in-hand manipulation. This paper aims to develop tools that establish how many synergies should be involved in a grasp to guarantee stability and efficiency, depending on the task and on the hand embodiment. Through the analysis of a quasi-static model, grasp structural properties related to contact force and object motion controllability are defined. Different compliant sources are considered, for a generalization of the discussion. In particular, a compliant model for synergies assumed, referred to as “soft synergies,” is discussed. The controllable internal forces and motions of the grasped object are related to the actuated inputs. This paper investigates to what extent a hand with many joints can ex- loit postural synergies to control force and motion of the grasped object.

10aHaptics10aRobotics1 aPrattichizzo, D1 aMalvezzi, M1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/motion-and-force-controllability-precision-grasps-hands-actuated-soft-synergies.html00574nas a2200169 4500008004100000245013700041210006900178300001600247653001300263100001500276700001500291700001700306700002000323700001500343700001500358856003100373 2013 eng d00aOptimal Control and Design Guidelines for Soft Jumping Robots: Series Elastic Actuation and Parallel Elastic Actuation in comparison0 aOptimal Control and Design Guidelines for Soft Jumping Robots Se a2477 - 248410aRobotics1 aIncaini, R1 aSestini, L1 aGarabini, M.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. u10.1109/ICRA.2013.6630914 00546nas a2200181 4500008004100000245008000041210006900121300001400190653001300204100001200217700001700229700001800246700001500264700002000279700001500299700002000314856003000334 2013 eng d00aOptimal Control for Maximizing Velocity of the CompActTM Compliant Actuator0 aOptimal Control for Maximizing Velocity of the CompActTM Complia a516 - 52210aRobotics1 aChen, L1 aGarabini, M.1 aLaffranchi, M1 aKashiri, N1 aTsagarakis, N G1 aBicchi, A.1 aCaldwell, D. G. u10.1109/ICRA.2013.663062300605nas a2200181 4500008004100000245006500041210006400106260002000170300001400190653002100204653001300225100001500238700001300253700001300266700001600279700001500295856011300310 2013 eng d00aPacket-based dynamic control for nonlinear networked systems0 aPacketbased dynamic control for nonlinear networked systems aFlorence, Italy a6597,660310aEmbedded Control10aRobotics1 aFalasca, S1 aGamba, M1 aGreco, L1 aChaillet, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/packet-based-dynamic-control-nonlinear-networked-systems.html01440nas a2200205 4500008004100000022002200041245006800063210006700131260005400198300001400252520076100266653002101027653001301048100001401061700001501075700001501090700001301105700001501118856010101133 2013 eng d a978-1-4799-0995-700aPacket-Based Dynamic Control of a Furuta Pendulum over Ethernet0 aPacketBased Dynamic Control of a Furuta Pendulum over Ethernet aPlatanias-Chania, Crete, Greecec25-28 June 2013  a464 - 4703 a

This paper presents experimental results of the application of Packet-Based Control approach with dynamic controller on a real plant: the Furuta Pendulum. Despite its easiness of realization, Furuta Pendulum presents some features useful for our purposes, such as pretty non-linear dynamics, unstable equilibrium point and heavy dynamical inaccuracies. The network communication channel has been implemented using an Ethernet network. Packet-Based controller has been tested and compared with a classic local controller for different time-varying actuation delays. Results obtained corroborate the validity of the proposed architecture and highlight the robustness of this approach in the presence of actuation delays.

10aEmbedded Control10aRobotics1 aFabbri, T1 aFenucci, D1 aFalasca, S1 aGamba, M1 aBicchi, A. uhttp://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6608763&queryText%3Dfalasca+gamba00487nas a2200145 4500008004100000245008600041210006900127260004100196300001600237653001300253100001400266700001500280700001500295856003100310 2013 eng d00aA real time robust observer for an agonist antagonist variable stiffness actuator0 areal time robust observer for an agonist antagonist variable sti aKarlsruhe, Germany, May 6-10, 2013  a3988 - 399310aRobotics1 aMenard, T1 aGrioli, G.1 aBicchi, A. u10.1109/ICRA.2013.6631139 00575nas a2200145 4500008004100000245009600041210006900137300001600206490000700222653002100229653001300250100001700263700001500280856013400295 2013 eng d00aOn the Robust Synthesis of Logical Consensus Algorithms for Distributed Intrusion Detection0 aRobust Synthesis of Logical Consensus Algorithms for Distributed a2339 - 23500 v4910aEmbedded Control10aRobotics1 aFagiolini, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/robust-synthesis-logical-consensus-algorithms-distributed-intrusion-detection.html00621nas a2200157 4500008003900000245010200039210006900141260002000210300001600230653001300246100001500259700001800274700001900292700001500311856013700326 2013 d00aShortest paths for wheeled robots with limited Field-Of-View: introducing the vertical constraint0 aShortest paths for wheeled robots with limited FieldOfView intro aFlorence, Italy a5143 - 514910aRobotics1 aSalaris, P1 aCristofaro, A1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-wheeled-robots-limited-field-view-introducing-vertical-constraint.html00632nas a2200169 4500008003900000245008700039210006900126260002600195653001300221100001500234700001800249700001700267700001600284700001500300700001500315856013200330 2013 d00aSoft-Actuators in Cyclic Motion: Analytical Optimization of Stiffness and Pre-Load0 aSoftActuators in Cyclic Motion Analytical Optimization of Stiffn aAtlanta, Georgia, USA10aRobotics1 aVelasco, A1 aGasparri, G M1 aGarabini, M.1 aMalagia, L.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/soft-actuators-cyclic-motion-analytical-optimization-stiffness-and-pre-load.html00584nas a2200157 4500008003900000245008200039210006900121260002400190300001000214653002100224653001300245100001500258700001300273700001500286856012500301 2013 d00aA Strategy for Dynamic Controller Emulation in Packet-Based Networked Control0 aStrategy for Dynamic Controller Emulation in PacketBased Network aReykjavík, Iceland a29-3810aEmbedded Control10aRobotics1 aFalasca, S1 aGamba, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/strategy-dynamic-controller-emulation-packet-based-networked-control.html01855nas a2200169 4500008004100000024003500041245005800076210005600134300001200190490000700202520130800209653001301517100001601530700001501546700001501561856010901576 2013 eng d ahttp://arxiv.org/abs/1206.055600aSynergy-Based Hand Pose Sensing: Optimal Glove Design0 aSynergyBased Hand Pose Sensing Optimal Glove Design a396-4060 v323 a

In this paper we study the problem of improving human hand pose sensing device performance by exploiting the knowledge on how humans most frequently use their hands in grasping tasks. In a companion paper we studied the problem of maximizing the reconstruction accuracy of the hand pose from partial and noisy data provided by any given pose sensing device (a sensorized "glove") taking into account statistical a priori information. In this paper we consider the dual problem of how to design pose sensing devices, i.e. how and where to place sensors on a glove, to get maximum information about the actual hand posture. We study the continuous case, whereas individual sensing elements in the glove measure a linear combination of joint angles, the discrete case, whereas each measure corresponds to a single joint angle, and the most general hybrid case, whereas both continuous and discrete sensing elements are available. The objective is to provide, for given a priori information and fixed number of measurements, the optimal design minimizing in average the reconstruction error. Solutions relying on the geometrical synergy definition as well as gradient flow-based techniques are provided. Simulations of reconstruction performance show the effectiveness of the proposed optimal design.

10aRobotics1 aBianchi, M.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/synergy-based-hand-pose-sensing-optimal-glove-design.html01808nas a2200157 4500008004100000245006400041210006200105300001300167490000700180520128900187653001301476100001601489700001501505700001501520856011501535 2013 eng d00aSynergy-based Hand Pose Sensing: Reconstruction Enhancement0 aSynergybased Hand Pose Sensing Reconstruction Enhancement a 407-4240 v323 a

Low-cost sensing gloves for reconstruction posture provide measurements which are limited under several regards. They are generated through an imperfectly known model, are subject to noise, and may be less than the number of Degrees of Freedom (DoFs) of the hand. Under these conditions, direct reconstruction of the hand posture is an ill-posed problem, and performance can be very poor. This paper examines the problem of estimating the posture of a human hand using(low-cost) sensing gloves, and how to improve their performance by exploiting the knowledge on how humans most frequently use their hands. To increase the accuracy of pose reconstruction without modifying the glove hardware - hence basically at no extra cost - we propose to collect, organize, and exploit information on the probabilistic distribution of human hand poses in common tasks. We discuss how a database of such an a priori information can be built, represented in a hierarchy of correlation patterns or postural synergies, and fused with glove data in a consistent way, so as to provide a good hand pose reconstruction in spite of insufficient and inaccurate sensing data. Simulations and experiments on a low-cost glove are reported which demonstrate the effectiveness of the proposed techniques.

10aRobotics1 aBianchi, M.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/synergy-based-hand-pose-sensing-reconstruction-enhancement.html00512nas a2200181 4500008004100000245005200041210004900093260003500142300001000177653001200187653001300199100001900212700001700231700002000248700001500268700001500283856003200298 2013 eng d00aA synergy-driven approach to a myoelectric hand0 asynergydriven approach to a myoelectric hand aJune 24-26, 2013, Seattle, WA. a1 - 610aHaptics10aRobotics1 aGodfrey, S. B.1 aAjoudani, A.1 aCatalano, M. G.1 aGrioli, G.1 aBicchi, A. u10.1109/ICORR.2013.6650377 00488nas a2200157 4500008004100000245007700041210006900118300001600187653001300203100001600216700001500232700001700247700002000264700001500284856003100299 2013 eng d00aSynGrasp: a MATLAB Toolbox for Grasp Analysis of Human and Robotic Hands0 aSynGrasp a MATLAB Toolbox for Grasp Analysis of Human and Roboti a1088 - 109310aRobotics1 aMalvezzi, M1 aGioioso, G1 aSalvietti, G1 aPrattichizzo, D1 aBicchi, A. u10.1109/ICRA.2013.6630708 00529nas a2200169 4500008004100000245008900041210006900130300001600199653001300215100001500228700001700243700002000260700001400280700001500294700002000309856003000329 2013 eng d00aTele-Impedance based Stiffness and Motion Augmentation for a Knee Exoskeleton Device0 aTeleImpedance based Stiffness and Motion Augmentation for a Knee a2194 - 220010aRobotics1 aKaravas, N1 aAjoudani, A.1 aTsagarakis, N G1 aSaglia, J1 aBicchi, A.1 aCaldwell, D. G. u10.1109/ICRA.2013.663087200660nas a2200193 4500008004100000245006700041210006600108260003100174300001600205653001200221653001300233100001700246700001900263700002000282700001500302700002000317700001500337856011400352 2013 eng d00aTeleimpedance Control of a Synergy-Driven Anthropomorphic Hand0 aTeleimpedance Control of a SynergyDriven Anthropomorphic Hand aTokyo, JapancNovember 3-7 a1985 - 199110aHaptics10aRobotics1 aAjoudani, A.1 aGodfrey, S. B.1 aCatalano, M. G.1 aGrioli, G.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/teleimpedance-control-synergy-driven-anthropomorphic-hand.html02056nas a2200457 4500008004100000245004300041210004200084260001200126300001600138490000700154520088900161653001301050653001801063653003301081100002001114700002201134700001501156700001401171700002001185700001501205700002001220700001601240700001401256700001401270700001701284700001901301700001501320700001601335700001501351700001401366700001801380700001501398700001301413700001901426700002001445700001801465700001601483700001601499700001201515856007101527 2013 eng d00aVariable Impedance Actuators: a Review0 aVariable Impedance Actuators a Review c12/2013 a1601–16140 v613 a

Variable Impedance Actuators (VIA) have received increasing attention in recent years as many novel applications involving interactions with an unknown and dynamic environment including humans require actuators with dynamics that are not well-achieved by classical stiff actuators. This paper presents an overview of the different VIAs developed and proposes a classification based on the principles through which the variable stiffness and damping are achieved. The main classes are active impedance by control, inherent compliance and damping actuators, inertial actuators, and combinations of them, which are then further divided into subclasses. This classification allows for designers of new devices to orientate and take inspiration and users of VIA’s to be guided in the design and implementation process for their targeted application.

10aRobotics10aSoft robotics10aVariable Impedance Actuators1 aVanderborght, B1 aAlbu-Schaeffer, A1 aBicchi, A.1 aBurdet, E1 aCaldwell, D. G.1 aCarloni, R1 aCatalano, M. G.1 aEiberger, O1 aFriedl, W1 aGanesh, G1 aGarabini, M.1 aGrebenstein, M1 aGrioli, G.1 aHaddadin, S1 aHoppner, H1 aJafari, A1 aLaffranchi, M1 aLefeber, D1 aPetit, F1 aStramigioli, S1 aTsagarakis, N G1 aDamme, Van, M1 aHam, Van, R1 aVisser, L C1 aWolf, S uhttp://www.sciencedirect.com/science/article/pii/S092188901300118800640nas a2200169 4500008004100000245008200041210006900123260004900192300001700241653001300258100001500271700002000286700001700306700001200323700001500335856012000350 2012 eng d00aAdaptive Synergies: an approach to the design of under-actuated robotic hands0 aAdaptive Synergies an approach to the design of underactuated ro aVilamoura, Algarve, PortugalcOctober 7 - 12 a1251 - 1256 10aRobotics1 aGrioli, G.1 aCatalano, M. G.1 aSilvestro, E1 aTono, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-synergies-approach-design-under-actuated-robotic-hands.html00549nas a2200181 4500008004100000245004900041210004900090260001700139300000900156653001300165100002000178700001500198700001400213700001600227700001400243700001500257856009500272 2012 eng d00aAdaptive Synergies for a Humanoid Robot Hand0 aAdaptive Synergies for a Humanoid Robot Hand aOsaka, Japan a7-1410aRobotics1 aCatalano, M. G.1 aGrioli, G.1 aSerio, A.1 aFarnioli, E1 aPiazza, C1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-synergies-humanoid-robot-hand.html00691nas a2200193 4500008004100000245008100041210006900122260001300191300001400204490004600218653001300264100002000277700001600297700001500313700001500328700001500343700001500358856012400373 2012 eng d00aArtificially Rendered Cutaneous Cues for a New Generation of Haptic Displays0 aArtificially Rendered Cutaneous Cues for a New Generation of Hap bSpringer a171 - 1880 vImmersive Multimodal Interactive Presence10aRobotics1 aScilingo, E. P.1 aBianchi, M.1 aVanello, N1 aHartwig, V1 aLandini, L1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/artificially-rendered-cutaneous-cues-new-generation-haptic-displays.html00503nas a2200145 4500008004100000245005700041210005600098260002200154653001300176100001400189700001700203700001800220700001500238856010400253 2012 eng d00aCalibration and Test of a Multi-Touch Tactile Object0 aCalibration and Test of a MultiTouch Tactile Object aAlgrave, Portugal10aRobotics1 aSerio, A.1 aGabiccini, M1 aSarakoglou, I1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/calibration-and-test-multi-touch-tactile-object.html00538nas a2200145 4500008004100000245007800041210006900119300001300188490000700201653001300208100001900221700001500240700001300255856012400268 2012 eng d00aConsensus Computation in Unreliable Networks: A System Theoretic Approach0 aConsensus Computation in Unreliable Networks A System Theoretic  a90 - 1040 v5710aRobotics1 aPasqualetti, F1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/consensus-computation-unreliable-networks-system-theoretic-approach.html00537nas a2200145 4500008004100000245007600041210006900117300001600186490000700202653001300209100001300222700001600235700001500251856012500266 2012 eng d00aExploiting Packet Size in Uncertain Nonlinear Networked Control Systems0 aExploiting Packet Size in Uncertain Nonlinear Networked Control  a2801 - 28110 v4810aRobotics1 aGreco, L1 aChaillet, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/exploiting-packet-size-uncertain-nonlinear-networked-control-systems.html00612nas a2200145 4500008004100000245010500041210006900146260003700215300001600252653001300268100001700281700001600298700001500314856013700329 2012 eng d00aGrasp and Manipulation Analysis for Synergistic Underactuated Hands Under General Loading Conditions0 aGrasp and Manipulation Analysis for Synergistic Underactuated Ha aSaint Paul, MN, USAcMay 14 - 18 a2836 - 284210aRobotics1 aGabiccini, M1 aFarnioli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/grasp-and-manipulation-analysis-synergistic-underactuated-hands-under-general-loading00671nas a2200181 4500008004100000245011400041210006900155300001200224490000700236653002100243653001300264100001700277700001500294700001100309700001600320700001500336856013800351 2012 eng d00aInteracting with networks: How does structure relate to controllability in single-leader, consensus networks?0 aInteracting with networks How does structure relate to controlla a66 - 730 v3210aEmbedded Control10aRobotics1 aEgerstedt, M1 aMartini, S1 aCao, M1 aCamlibel, K1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/interacting-networks-how-does-structure-relate-controllability-single-leader-consensus00682nas a2200205 4500008004100000245008000041210006900121300001400190490000700204653001300211100001600224700001600240700001400256700001400270700001500284700001700299700001500316700002200331856012300353 2012 eng d00aOn Making Robots Understand Safety: Embedding Injury Knowledge into Control0 aMaking Robots Understand Safety Embedding Injury Knowledge into  a1578-16020 v3110aRobotics1 aHaddadin, S1 aHaddadin, S1 aKhoury, A1 aRokahr, T1 aParusel, S1 aBurgkart, R.1 aBicchi, A.1 aAlbu-Schaeffer, A uhttp://www.centropiaggio.unipi.it/publications/making-robots-understand-safety-embedding-injury-knowledge-control.html00687nas a2200181 4500008004100000024003600041245011600077210006900193300001400262490000700276653001200283653001300295100002000308700001600328700001700344700001500361856012900376 2012 eng d aAvailable online 17 August 201100aOn the Manipulability Ellipsoids of Underactuated Robotic Hands with Compliance Robotics and Autonomous Systems0 aManipulability Ellipsoids of Underactuated Robotic Hands with Co a337 - 3460 v6010aHaptics10aRobotics1 aPrattichizzo, D1 aMalvezzi, M1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/manipulability-ellipsoids-underactuated-robotic-hands-compliance-robotics-and00588nas a2200169 4500008004100000245006100041210006000102260003700162300001700199653001300216100001700229700001700246700002000263700001500283700001500298856010500313 2012 eng d00aOptimality Principles in Stiffness Control: The VSA Kick0 aOptimality Principles in Stiffness Control The VSA Kick aSaint Paul, MN, USAcMay 14 - 18 a3341 - 3346 10aRobotics1 aGarabini, M.1 aPassaglia, A1 aBelo, F., A. W.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimality-principles-stiffness-control-vsa-kick.html00652nas a2200181 4500008004100000245007500041210006900116260003700185300001700222653001300239100001500252700001500267700002000282700001700302700001400319700001500333856012200348 2012 eng d00aPassive impedance control of a Qboid multi-DOF VSA-CubeBot manipulator0 aPassive impedance control of a Qboid multiDOF VSACubeBot manipul aSaint Paul, MN, USAcMay 14 - 18 a3335 - 3340 10aRobotics1 aMancini, M1 aGrioli, G.1 aCatalano, M. G.1 aGarabini, M.1 aBonomo, F1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/passive-impedance-control-qboid-multi-dof-vsa-cubebot-manipulator.html00565nas a2200145 4500008004100000245009300041210006900134300001300203490000700216653001300223100001500236700001900251700001500270856013400285 2012 eng d00aShortest Paths for Finned, Winged, Legged and Wheeled Vehicles with Side-Looking Sensors0 aShortest Paths for Finned Winged Legged and Wheeled Vehicles wit a997-10170 v3110aRobotics1 aSalaris, P1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-finned-winged-legged-and-wheeled-vehicles-side-looking-sensors.html00522nas a2200145 4500008004100000245005400041210005300095260004900148300001700197653001300214100001600227700001500243700001500258856010300273 2012 eng d00aSynergy-based Optimal Desing of Hand Pose Sensing0 aSynergybased Optimal Desing of Hand Pose Sensing aVilamoura, Algarve, PortugalcOctober 7 - 12 a3929 - 3935 10aRobotics1 aBianchi, M.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/synergy-based-optimal-desing-hand-pose-sensing.html00580nas a2200169 4500008004100000024001700041245006300058210005600121260003700177300001700214653001300231100001500244700001400259700001700273700001500290856010500305 2012 eng d ap. 550 - 55600aOn the Synthesis of Feasible and Prehensile Robotic Grasps0 aSynthesis of Feasible and Prehensile Robotic Grasps aSaint Paul, MN, USAcMay 14 - 18 ap. 550 - 55610aRobotics1 aRosales, C1 aSuarez, R1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/synthesis-feasible-and-prehensile-robotic-grasps.html00641nas a2200169 4500008004100000245009200041210006900133260001700202300001200219653001300231100001700244700001700261700002000278700002200298700001500320856013600335 2012 eng d00aTele-Impedance: Exploring the Role of Common-Mode and Configuration-Dependant Stiffness0 aTeleImpedance Exploring the Role of CommonMode and Configuration aOsaka, Japan a363-36910aRobotics1 aAjoudani, A.1 aGabiccini, M1 aTsagarakis, N G1 aAlbu-Schaeffer, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tele-impedance-exploring-role-common-mode-and-configuration-dependant-stiffness.html00596nas a2200157 4500008004100000245009100041210006900132260001200201300001600213490000900229653001300238100001700251700002000268700001500288856013500303 2012 eng d00aTele-impedance: Teleoperation with Impedance Regulation Using a Body-Machine Interface0 aTeleimpedance Teleoperation with Impedance Regulation Using a Bo c11/2012 a1643 - 16560 v 31 10aRobotics1 aAjoudani, A.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tele-impedance-teleoperation-impedance-regulation-using-body-machine-interface.html00591nas a2200145 4500008004100000245008500041210006900126260003700195300001500232653001300247100001700260700002000277700001500297856013300312 2012 eng d00aTele-Impedance: Towards Transferring Human Impedance Regulation Skills to Robots0 aTeleImpedance Towards Transferring Human Impedance Regulation Sk aSaint Paul, MN, USAcMay 14 - 18 a382 - 388 10aRobotics1 aAjoudani, A.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tele-impedance-towards-transferring-human-impedance-regulation-skills-robots.html00594nas a2200181 4500008004100000245006100041210005800102260001700160653001300177100001600190700001400206700002000220700002000240700001700260700001500277700001500292856010500307 2012 eng d00aTowards variable impedance assembly: the VSA peg-in-hole0 aTowards variable impedance assembly the VSA peginhole aOsaka, Japan10aRobotics1 aBalletti, L1 aRocchi, A1 aBelo, F., A. W.1 aCatalano, M. G.1 aGarabini, M.1 aGrioli, G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/towards-variable-impedance-assembly-vsa-peg-hole.html00704nas a2200205 4500008004100000245006900041210006700110260004900177300001400226653001300240100001600253700001600269700001400285700001400299700001500313700001700328700001500345700002200360856011600382 2012 eng d00aA truly safely moving robot has to know what injury it may cause0 atruly safely moving robot has to know what injury it may cause aVilamoura, Algarve, PortugalcOctober 7 - 12 a5406-541310aRobotics1 aHaddadin, S1 aHaddadin, S1 aKhoury, A1 aRokahr, T1 aParusel, S1 aBurgkart, R.1 aBicchi, A.1 aAlbu-Schaeffer, A uhttp://www.centropiaggio.unipi.it/publications/truly-safely-moving-robot-has-know-what-injury-it-may-cause.html00638nas a2200181 4500008004100000245007900041210006900120260003500189300001200224653001200236653001300248100001600261700001500277700001300292700001800305700001500323856011800338 2012 eng d00aOn the Use of Postural Synergies to Improve Human Hand Pose Reconstruction0 aUse of Postural Synergies to Improve Human Hand Pose Reconstruct aVancouver, CanadacMarch 4 - 7 a91 - 9810aHaptics10aRobotics1 aBianchi, M.1 aSalaris, P1 aTurco, A1 aCarbonaro, N.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/use-postural-synergies-improve-human-hand-pose-reconstruction.html00658nas a2200193 4500008004100000245006300041210006100104260003700165300001600202653001300218100002000231700001500251700001700266700002000283700001700303700002000320700001500340856010900355 2012 eng d00aA Variable Damping module for Variable Impedance Actuation0 aVariable Damping module for Variable Impedance Actuation aSaint Paul, MN, USAcMay 14 - 18 a2666 - 267210aRobotics1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aBelo, F., A. W.1 aDi Basco, A.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/variable-damping-module-variable-impedance-actuation.html00976nas a2200337 4500008004100000245006400041210006300105653001300168100002000181700002200201700001500223700001400238700002000252700001500272700002000287700001400307700001700321700001500338700001600353700001400369700001800383700001500401700001300416700001900429700002000448700001800468700001600486700001600502700001200518856010800530 2012 eng d00aVariable Impedance Actuators: Moving the Robots of Tomorrow0 aVariable Impedance Actuators Moving the Robots of Tomorrow10aRobotics1 aVanderborght, B1 aAlbu-Schaeffer, A1 aBicchi, A.1 aBurdet, E1 aCaldwell, D. G.1 aCarloni, R1 aCatalano, M. G.1 aGanesh, G1 aGarabini, M.1 aGrioli, G.1 aHaddadin, S1 aJafari, A1 aLaffranchi, M1 aLefeber, D1 aPetit, F1 aStramigioli, S1 aTsagarakis, N G1 aDamme, Van, M1 aHam, Van, R1 aVisser, L C1 aWolf, S uhttp://www.centropiaggio.unipi.it/publications/variable-impedance-actuators-moving-robots-tomorrow.html00654nas a2200193 4500008004100000245006200041210006000103260004900163300001700212653001300229100001500242700002000257700001600277700001700293700001500310700001500325700001500340856010500355 2012 eng d00a Velvet fingers: A dexterous gripper with active surfaces0 aVelvet fingers A dexterous gripper with active surfaces aVilamoura, Algarve, PortugalcOctober 7 - 12 a1257 - 1263 10aRobotics1 aTincani, V1 aCatalano, M. G.1 aFarnioli, E1 aGarabini, M.1 aGrioli, G.1 aFantoni, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/velvet-fingers-dexterous-gripper-active-surfaces.html00567nas a2200145 4500008004100000245007600041210006900117260003400186653002100220653001300241100001500254700001700269700001500286856012000301 2011 eng d00aBehavior classification, security, and consensus in societies of robots0 aBehavior classification security and consensus in societies of r aPisa, ItalycSeptember, 7 - 910aEmbedded Control10aRobotics1 aMartini, S1 aFagiolini, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/behavior-classification-security-and-consensus-societies-robots.html00707nas a2200193 4500008004100000024001300041245009200054210006900146260003100215300001200246653002100258653001300279100001500292700001700307700001900324700001700343700001500360856013800375 2011 eng d ap. 32-3900aDecentralized Species Classification in Societies of Autonomous and Heterogenous Robots0 aDecentralized Species Classification in Societies of Autonomous  aShangai, ChinacMay 9 - 13 a32 - 3910aEmbedded Control10aRobotics1 aMartini, S1 aFagiolini, A1 aZichittella, G1 aEgerstedt, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-species-classification-societies-autonomous-and-heterogenous-robots.html00594nas a2200169 4500008004100000245006600041210006400107260003100171300001600202653001300218100001400231700001500245700001900260700002000279700001500299856011000314 2011 eng d00aA decoupled Impedance observer for a Variable Stiffness Robot0 adecoupled Impedance observer for a Variable Stiffness Robot aShangai, ChinacMay 9 - 13 a5548 - 555310aRobotics1 aSerio, A.1 aGrioli, G.1 aSardellitti, I1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decoupled-impedance-observer-variable-stiffness-robot.html00573nas a2200157 4500008004100000245008000041210006900121300001400190490000700204653002100211653001300232100001300245700001800258700001500276856012400291 2011 eng d00aDesign and Stability Analysis for Anytime Control via Stochastic Scheduling0 aDesign and Stability Analysis for Anytime Control via Stochastic a571 - 5850 v5610aEmbedded Control10aRobotics1 aGreco, L1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-and-stability-analysis-anytime-control-stochastic-scheduling.html00630nas a2200157 4500008004100000245010200041210006900143260003100212300001600243653001200259653001300271100001700284700001800301700001500319856013800334 2011 eng d00aDynamic Optimization of Tendon Tensions in Biomorphically Designed Hands with Rolling Constraints0 aDynamic Optimization of Tendon Tensions in Biomorphically Design aShangai, ChinacMay 9 - 13 a2698 - 270410aHaptics10aRobotics1 aGabiccini, M1 aBranchetti, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/dynamic-optimization-tendon-tensions-biomorphically-designed-hands-rolling-constraints00540nas a2200145 4500008004100000245006300041210006300104260003600167300001600203653001300219100001600232700001900248700001500267856011200282 2011 eng d00aEmbodying Desired Behavior in Variable Stiffness Actuators0 aEmbodying Desired Behavior in Variable Stiffness Actuators aMilano, italycAugust 28 - Sept a9733 - 973810aRobotics1 aVisser, L C1 aStramigioli, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/embodying-desired-behavior-variable-stiffness-actuators.html00603nas a2200157 4500008004100000245007600041210006900117260003600186300001800222653002100240653001300261100001300274700001600287700001500303856012700318 2011 eng d00aExploiting Packet Size in Uncertain Nonlinear Networked Control Systems0 aExploiting Packet Size in Uncertain Nonlinear Networked Control  aMilano, italycAugust 28 - Sept a14404 - 1440910aEmbedded Control10aRobotics1 aGreco, L1 aChaillet, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/exploiting-packet-size-uncertain-nonlinear-networked-control-systems.html-000591nas a2200169 4500008004100000245006200041210006200103260004000165300001400205653002100219653001300240100001500253700001900268700001800287700001500305856010100320 2011 eng d00aFrom Optimal Planning to Visual Servoing with Limited FOV0 aFrom Optimal Planning to Visual Servoing with Limited FOV aS. Francisco, USAcSeptember 25 - 3 a2817-282410aEmbedded Control10aRobotics1 aSalaris, P1 aPallottino, L.1 aHutchinson, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-planning-visual-servoing-limited-fov.html00563nas a2200145 4500008004100000245007200041210006900113260004000182300001600222653001300238100001900251700001500270700001300285856011900298 2011 eng d00aA graph theoretic characterization of power network vulnerabilities0 agraph theoretic characterization of power network vulnerabilitie aSan Francisco, CAcJune 29 - July 1 a3918 - 392310aRobotics1 aPasqualetti, F1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/graph-theoretic-characterization-power-network-vulnerabilities.html00461nas a2200169 4500008004100000245002200041210001800063260003400081653001200115653001300127100001400140700002000154700001500174700001700189700001500206856007000221 2011 eng d00aThe Hand Embodied0 aHand Embodied aPisa, ItalycSeptember, 7 - 910aHaptics10aRobotics1 aSerio, A.1 aCatalano, M. G.1 aGrioli, G.1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/hand-embodied.html00548nas a2200145 4500008004100000245006800041210006700109260003400176653001200210653001300222100001600235700002000251700001500271856011600286 2011 eng d00aHaptic interfaces: new strategies to convey tactile information0 aHaptic interfaces new strategies to convey tactile information aPisa, ItalycSeptember, 7 - 910aHaptics10aRobotics1 aBianchi, M.1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/haptic-interfaces-new-strategies-convey-tactile-information.html01685nas a2200169 4500008004100000245010100041210006900142260001700211300001400228490000700242520107300249653001301322100001501335700001501350700001501365856013501380 2011 eng d00aLeft invertibility of discrete-time output-quantized systems: the linear case with finite inputs0 aLeft invertibility of discretetime outputquantized systems the l cNovember, 16 a117 - 1390 v233 a

This paper studies left invertibility of discrete-time linear outputquantized systems. Quantized outputs are generated according to a given partition of the state-space, while inputs are sequences on a nite alphabet. Left invertibility, i.e. injectivity of I/O map, is reduced to left D-invertibility, under suitable conditions. While left invertibility takes into account membership to sets of a given partition, left D-invertibility considers only membership to a single set, and is much easier to detect. The condition under which left invertibility and left D-invertibility are equivalent is that the elements of the dynamic matrix of the system form an algebraically independent set. Our main result is a method to compute left D-invertibility (so also left invertibility for a full measure matrix set) for all linear systems with no eigenvalue of modulus one. Therefore we are able to check left invertibility of output-quantized linear systems for a full measure matrices set. Some examples are presented to show the application of the proposed method.

10aRobotics1 aDubbini, N1 aPiccoli, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/left-invertibility-discrete-time-output-quantized-systems-linear-case-finite-inputs01674nas a2200169 4500008004100000245006300041210006200104260003600166300001800202520109500220653002101315653001301336100001501349700001301364700001501377856011201392 2011 eng d00aLeft invertibility of output-quantized MISO linear systems0 aLeft invertibility of outputquantized MISO linear systems aMilano, italycAugust 28 - Sept a11278 - 112833 a

This paper studies left invertibility of single-output discrete-time quantized linear systems. Quantized outputs are generated according to a given partition of the state-space, while inputs are sequences on a finite alphabet. Left invertibility deals with the possibility of recovering unknown inputs from the only knowledge of the outputs. It is reduced, under suitable conditions, to left D-invertibility: while left invertibility takes into account membership to sets of a given partition, left D-invertibility considers only membership to a single set, and is easily (and algorithmically) detectable. Our main result is a sufficient condition for the equivalence between left invertibility and left D-invertibility in MISO system. In unidimensional systems the equivalence is valid except at most a finite (and computable) number of cases. These results allows the effective detection of left invertibility by means of left Dinvertibility, which is algorithmically detectable. An example with effective computations is presented to show the application of the proposed method.

10aEmbedded Control10aRobotics1 aDubbini, N1 aMonge, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/left-invertibility-output-quantized-miso-linear-systems.html00514nas a2200157 4500008004100000245005700041210005700098300001600155490000800171653001200179653001300191100001500204700001700219700001600236856010400252 2011 eng d00aModeling Natural and Artificial Hands with Synergies0 aModeling Natural and Artificial Hands with Synergies a3153 - 31610 v36610aHaptics10aRobotics1 aBicchi, A.1 aGabiccini, M1 aSantello, M uhttp://www.centropiaggio.unipi.it/publications/modeling-natural-and-artificial-hands-synergies.html00526nas a2200133 4500008004100000245007800041210006900119653002100188653001300209100001500222700001900237700001500256856012100271 2011 eng d00aOptimal synthesis for nonholonomic vehicles with constrained side sensors0 aOptimal synthesis for nonholonomic vehicles with constrained sid10aEmbedded Control10aRobotics1 aSalaris, P1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-synthesis-nonholonomic-vehicles-constrained-side-sensors.html00621nas a2200169 4500008004100000245007200041210006900113260004000182300001600222653001300238100001700251700001700268700002000285700001500305700001500320856011600335 2011 eng d00aOptimality Principles in Variable Stiffness Control: the VSA Hammer0 aOptimality Principles in Variable Stiffness Control the VSA Hamm aS. Francisco, USAcSeptember 25 - 3 a3770 - 377510aRobotics1 aGarabini, M.1 aPassaglia, A1 aBelo, F., A. W.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimality-principles-variable-stiffness-control-vsa-hammer.html00494nas a2200133 4500008004100000245006200041210005900103260003100162300001600193653001300209100001500222700001500237856010800252 2011 eng d00aA Real-time Parametric Stiffness Observer for VSA devices0 aRealtime Parametric Stiffness Observer for VSA devices aShangai, ChinacMay 9 - 13 a5535 - 554010aRobotics1 aGrioli, G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/real-time-parametric-stiffness-observer-vsa-devices.html00569nas a2200169 4500008004100000245005200041210005200093260003600145300001800181653002100199653001300220100001500233700001800248700001700266700001500283856010100298 2011 eng d00aRobust Network Agreement on Logical Information0 aRobust Network Agreement on Logical Information aMilano, italycAugust 28 - Sept a13905 - 1391110aEmbedded Control10aRobotics1 aMartini, S1 aDi Baccio, D.1 aFagiolini, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/robust-network-agreement-logical-information.html00575nas a2200169 4500008004100000245007500041210006800116300001400184490000700198653001200205653001300217100001700230700001500247700002000262700001600282856010700298 2011 eng d00aOn the Role of Hand Synergies in the Optimal Choice of Grasping Forces0 aRole of Hand Synergies in the Optimal Choice of Grasping Forces a235 - 2520 v3110aHaptics10aRobotics1 aGabiccini, M1 aBicchi, A.1 aPrattichizzo, D1 aMalvezzi, M uhttp://www.centropiaggio.unipi.it/publications/role-hand-synergies-optimal-choice-grasping-forces.html00484nas a2200157 4500008004100000245003600041210003600077260003100113300001600144653002100160653001300181100001500194700001900209700001500228856008300243 2011 eng d00aShortest Paths With Side Sensor0 aShortest Paths With Side Sensor aShangai, ChinacMay 9 - 13 a4875 - 488210aEmbedded Control10aRobotics1 aSalaris, P1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-side-sensor.html00593nas a2200157 4500008004100000245007900041210006900120260003400189653001200223653001300235100001700248700001600265700001600281700001500297856012300312 2011 eng d00aStructural Properties of Compliant Grasps with Underactuated Robotic Hands0 aStructural Properties of Compliant Grasps with Underactuated Rob aBologna, ItalycSeptember, 1210aHaptics10aRobotics1 aGabiccini, M1 aFarnioli, E1 aMalvezzi, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/structural-properties-compliant-grasps-underactuated-robotic-hands.html00623nas a2200145 4500008004100000245011300041210006900154260003800223300001400261653001300275100001700288700002000305700001500325856013700340 2011 eng d00aTele-Impedance: Preliminary Results on Measuring and Replicating Human Arm Impedance in Tele Operated Robots0 aTeleImpedance Preliminary Results on Measuring and Replicating H aPhuket, ThailandcDecember 7 - 11 a216 - 22310aRobotics1 aAjoudani, A.1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tele-impedance-preliminary-results-measuring-and-replicating-human-arm-impedance-tele00729nas a2200217 4500008004100000245007600041210006900117260003400186653001300220100001500233700002000248700001700268700001400285700001400299700001500313700002000328700001500348700001500363700001700378856011600395 2011 eng d00aVariable stiffness actuators: muscles for the next generation of robots0 aVariable stiffness actuators muscles for the next generation of  aPisa, ItalycSeptember, 7 - 910aRobotics1 aGrioli, G.1 aCatalano, M. G.1 aGarabini, M.1 aBonomo, F1 aSerio, A.1 aSalaris, P1 aBelo, F., A. W.1 aMancini, M1 aBicchi, A.1 aPassaglia, A uhttp://www.centropiaggio.unipi.it/publications/variable-stiffness-actuators-muscles-next-generation-robots.html00708nas a2200193 4500008004100000245009400041210006900135260003100204300001600235653001300251100002000264700001500284700001700299700001400316700001500330700002000345700001500365856013400380 2011 eng d00aVSA - CubeBot. A modular variable stiffness platform for multi degrees of freedom systems0 aVSA CubeBot A modular variable stiffness platform for multi degr aShangai, ChinacMay 9 - 13 a5090 - 509510aRobotics1 aCatalano, M. G.1 aGrioli, G.1 aGarabini, M.1 aBonomo, F1 aMancini, M1 aTsagarakis, N G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/vsa-cubebot-modular-variable-stiffness-platform-multi-degrees-freedom-systems.html00668nas a2200169 4500008004100000024001900041245010200060210006900162260003000231300001500261653002100276653001300297100002000310700001500330700001500345856013800360 2010 eng d ap. 2539 - 254500a3 known landmarks are enough for solving planar bearing SLAM and fully reconstruct unknown inputs0 a3 known landmarks are enough for solving planar bearing SLAM and aSt. Louis MO USAcOctober a2539 -254510aEmbedded Control10aRobotics1 aBelo, F., A. W.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/3-known-landmarks-are-enough-solving-planar-bearing-slam-and-fully-reconstruct-unknown00806nas a2200169 4500008004100000245008700041210006900128300001200197490000600209520020400215653002100419653001300440100001500453700001700468700001500485856013600500 2010 eng d00aControllability analysis of multi-agent systems using relaxed equitable partitions0 aControllability analysis of multiagent systems using relaxed equ a100-1210 v23 a

This paper investigates the issue of how to make decentralised networks amenable to external control, i.e. how to ensure that they are appropriately organised so that they can be effectively

10aEmbedded Control10aRobotics1 aMartini, S1 aEgerstedt, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllability-analysis-multi-agent-systems-using-relaxed-equitable-partitions.html00613nas a2200169 4500008004100000024001700041245007200058210006900130260003300199300001400232653002100246653001300267100001200280700001900292700001500311856011700326 2010 eng d ap. 342 - 34900aControllability for Pairs of Vehicles Maintaining Constant Distance0 aControllability for Pairs of Vehicles Maintaining Constant Dista aAnchorage, AlaskacMay 3 - 8 a342 - 34910aEmbedded Control10aRobotics1 aWang, H1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllability-pairs-vehicles-maintaining-constant-distance.html00527nas a2200157 4500008004100000024001900041245005500060210005500115300001600170653002100186653001300207100001200220700001900232700001500251856010300266 2010 eng d ap. 2047 - 205400aControllability Properties for Aircraft Formations0 aControllability Properties for Aircraft Formations a2047 - 205410aEmbedded Control10aRobotics1 aWang, H1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllability-properties-aircraft-formations.html00669nas a2200205 4500008004100000024002000041245005700061210005700118260003300175300001600208653002100224653001300245100001700258700002000275700002000295700001500315700001400330700001500344856010400359 2010 eng d app. 4169 - 417400aDesign and Control of a Novel 3D Casting Manipulator0 aDesign and Control of a Novel 3D Casting Manipulator aAnchorage, AlaskacMay 3 - 8 a4169 - 417410aEmbedded Control10aRobotics1 aFagiolini, A1 aBelo, F., A. W.1 aCatalano, M. G.1 aAlicino, S1 aBonomo, F1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-and-control-novel-3d-casting-manipulator.html00661nas a2200169 4500008004100000024002000041245009300061210006900154260003300223300001600256653002100272653001300293100002000306700001500326700001500341856013500356 2010 eng d app. 3285 - 329100aDesign for Variable Stiffness Actuation based on Enumeration and Analysis of Performance0 aDesign for Variable Stiffness Actuation based on Enumeration and aAnchorage, AlaskacMay 3 - 8 a3285 - 329110aEmbedded Control10aRobotics1 aCatalano, M. G.1 aSchiavi, R1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-variable-stiffness-actuation-based-enumeration-and-analysis-performance.html01439nas a2200193 4500008004100000245006200041210006200103300001400165490000600179520084200185653002101027653001301048100001401061700001801075700001301093700001601106700001501122856010801137 2010 eng d00aDesign of Embedded Controllers Based on Anytime Computing0 aDesign of Embedded Controllers Based on Anytime Computing a492 - 5020 v63 a

In this paper, we present a methodology for designing embedded controllers based on the so-called anytime control paradigm. A control law is split into a sequence of subroutine calls, each one fulfilling a control goal and refining the result produced by the previous one. We propose a design methodology to define a feedback controller structured in accordance with this paradigm and show how a switching policy of selecting the controller subroutines can be designed that provides stability guarantees for the closed-loop system. The cornerstone of this construction is a stochastic model describing the probability of executing, in each activation of the controller, the different subroutines. We show how this model can be constructed for realistic real-time task sets and provide an experimental validation of the approach.

10aEmbedded Control10aRobotics1 aQuagli, A1 aFontanelli, D1 aGreco, L1 aPalopoli, L1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-embedded-controllers-based-anytime-computing.html00624nas a2200181 4500008004100000024001700041245006500058210006500123260003100188300001200219653002100231653001300252100001900265700001300284700001500297700001300312856011700325 2010 eng d ap. 263 - 26800aDistributed Estimation and Detection under Local Information0 aDistributed Estimation and Detection under Local Information aAnnecy, FrancecSept 13-14 a263-26810aEmbedded Control10aRobotics1 aPasqualetti, F1 aCarli, R1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/distributed-estimation-and-detection-under-local-information.html00601nas a2200181 4500008004100000024001900041245005800060210005800118260002700176300001600203653002100219653001300240100001900253700001300272700001500285700001300300856010600313 2010 eng d ap. 5961 - 596600aIdentifying Cyber Attacks via Local Model Information0 aIdentifying Cyber Attacks via Local Model Information aAtlanta, USAcDecember a5961 - 596610aEmbedded Control10aRobotics1 aPasqualetti, F1 aCarli, R1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/identifying-cyber-attacks-local-model-information.html01790nas a2200169 4500008004100000245008300041210006900124300001400193490000700207520120000214653002101414653001301435100001501448700001501463700001501478856012701493 2010 eng d00aLeft invertibility of discrete systems with finite inputs and quantized output0 aLeft invertibility of discrete systems with finite inputs and qu a798 - 8090 v833 a

The aim of this paper is to address left invertibility for dynamical systems with inputs and outputs in discrete sets. We study systems which evolve in discrete time within a continuous state-space; quantized outputs are generated by the system according to a given partition of the state-space, while inputs are arbitrary sequences of symbols in a finite alphabet, which are associated to specific actions on the system. Our main results are obtained under some contractivity hypotheses. The problem of left invertibility, i.e. recovering an unknown input sequence from the knowledge of the corresponding output string, is addressed using the theory of Iterated Function Systems (IFS), a tool developed for the study of fractals. We show how the IFS naturally associated to a system and the geometric properties of its attractor are linked to the invertibility property of the system. Our main result is a necessary and sufficient condition for left invertibility and uniform left invertibility for joint contractive systems. In addition, an algorithm is proposed to recover inputs from output strings. A few examples are presented to illustrate the application of the proposed method.

10aEmbedded Control10aRobotics1 aDubbini, N1 aPiccoli, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/left-invertibility-discrete-systems-finite-inputs-and-quantized-output.html01002nas a2200169 4500008004100000024002000041245008300061210006900144260002700213300001400240520039300254653001300647100001500660700001700675700001500692856012500707 2010 eng d app. 4078 - 408300aLeft invertibility of output-quantized systems: an application to cryptography0 aLeft invertibility of outputquantized systems an application to  aAtlanta, USAcDecember a4078-40833 a

In this paper a secure communication method is proposed, based on left invertibility of output-quantized dynamical systems. The sender uses an output-quantized linear system with a feedback function to encode messages, which are sequences of inputs of the system. So left invertibility property enables the receiver to recover the messages. The secret key is formed by the system

10aRobotics1 aDubbini, N1 aCarluccio, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/left-invertibility-output-quantized-systems-application-cryptography.html00516nas a2200133 4500008004100000022001400041245008100055210006900136260000800205653001300213100001500226700001600241856012500257 2010 eng d aUS769973100aMechanism of Motor reduction with variable rigidity and rapidly controllable0 aMechanism of Motor reduction with variable rigidity and rapidly  aUSA10aRobotics1 aBicchi, A.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/mechanism-motor-reduction-variable-rigidity-and-rapidly-controllable.html00634nas a2200181 4500008004100000024001800041245006800059210006600127260003800193300001400231653002100245653001300266100001500279700001500294700001400309700001500323856011400338 2010 eng d app. 273 - 27900aA Modular and Layered Cosimulator for Networked Control Systems0 aModular and Layered Cosimulator for Networked Control Systems aMarrakech, MoroccocJune, 23 - 25 a273 - 27910aEmbedded Control10aRobotics1 aFalasca, S1 aBelsito, C1 aQuagli, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/modular-and-layered-cosimulator-networked-control-systems.html00563nas a2200145 4500008004100000245008200041210006900123260002600192653001200218653001300230100002000243700001600263700001500279856012300294 2010 eng d00aOn motion and force controllability of grasping hands with postural synergies0 amotion and force controllability of grasping hands with postural aZaragoza, SpaincJune10aHaptics10aRobotics1 aPrattichizzo, D1 aMalvezzi, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/motion-and-force-controllability-grasping-hands-postural-synergies.html00521nas a2200157 4500008004100000024001900041245005400060210005400114300001600168653002100184653001300205100001200218700001900230700001500249856009900264 2010 eng d ap. 2263 - 226900aMotion planning for Formations of Dubins Vehicles0 aMotion planning for Formations of Dubins Vehicles a2263 - 226910aEmbedded Control10aRobotics1 aWang, H1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/motion-planning-formations-dubins-vehicles.html00557nas a2200181 4500008004100000024001800041245004000059210003800099260004400137300001400181653001200195653001300207100001600220700001400236700002000250700001500270856009000285 2010 eng d app. 108 - 11200aA new fabric based softness display0 anew fabric based softness display aWaltham,Massachusetts, USAcMarch 25-16 a108 - 11210aHaptics10aRobotics1 aBianchi, M.1 aSerio, A.1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/new-fabric-based-softness-display.html00481nas a2200121 4500008004100000245006900041210006500110260002600175653001300201100001500214700001500229856011500244 2010 eng d00aA Non-invasive Real-Time Method for Measuring Variable Stiffness0 aNoninvasive RealTime Method for Measuring Variable Stiffness aZaragoza, SpaincJune10aRobotics1 aGrioli, G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/non-invasive-real-time-method-measuring-variable-stiffness.html00702nas a2200181 4500008004100000024002000041245012300061210006900184300001600253653002100269653001300290100002100303700001500324700001700339700001500356700001200371856013700383 2010 eng d app. 5775 - 578000aObservability and Controllability Detection of Multi-Agent Systems through Decentralized Laplacian Spectrum Estimation0 aObservability and Controllability Detection of MultiAgent System a5775 - 578010aEmbedded Control10aRobotics1 aFranceschelli, M1 aMartini, S1 aEgerstedt, M1 aBicchi, A.1 aGiua, A uhttp://www.centropiaggio.unipi.it/publications/observability-and-controllability-detection-multi-agent-systems-through-decentralized00623nas a2200169 4500008004100000245009700041210006900138300001400207490000600221653001200227653001300239100002000252700001600272700001500288700001500303856013500318 2010 eng d00aRendering Softness: Integration of kinaesthetic and cutaneous information in a haptic device0 aRendering Softness Integration of kinaesthetic and cutaneous inf a109 - 1180 v310aHaptics10aRobotics1 aScilingo, E. P.1 aBianchi, M.1 aGrioli, G.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/rendering-softness-integration-kinaesthetic-and-cutaneous-information-haptic-device00514nas a2200133 4500008004100000245007500041210006800116260003000184653001200214653001300226100001700239700001500256856010900271 2010 eng d00aOn the Role of Hand Synergies in the Optimal Choice of Grasping Forces0 aRole of Hand Synergies in the Optimal Choice of Grasping Forces aZaragoza, SpaincJune, 2710aHaptics10aRobotics1 aGabiccini, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/role-hand-synergies-optimal-choice-grasping-forces.html-000661nas a2200181 4500008004100000024002000041245007700061210006900138260003700207300001600244653002100260653001300281100001700294700001500311700001800326700001500344856012000359 2010 eng d app. 5151 - 515600aA Self-Routing Protocol for Distributed Consensus on Logical Information0 aSelfRouting Protocol for Distributed Consensus on Logical Inform aTaipei, TaiwancOctober, 18 - 22 a5151 - 515610aEmbedded Control10aRobotics1 aFagiolini, A1 aMartini, S1 aDi Baccio, D.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/self-routing-protocol-distributed-consensus-logical-information.html00598nas a2200169 4500008004100000245007900041210006900120300001400189490000700203653002100210653001300231100001500244700001800259700001900277700001500296856011700311 2010 eng d00aShortest Paths for a Robot with Nonholonomic and Field-of-View Constraints0 aShortest Paths for a Robot with Nonholonomic and FieldofView Con a269 - 2810 v2610aEmbedded Control10aRobotics1 aSalaris, P1 aFontanelli, D1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-robot-nonholonomic-and-field-view-constraints.html00549nas a2200157 4500008004100000245007100041210006800112260001300180300001200193490000700205653001300212100001500225700001700240700001900257856011500276 2010 eng d00aTowards a Society of Robots: Behaviors, Misbehaviors, and Security0 aTowards a Society of Robots Behaviors Misbehaviors and Security cDecember a26 - 360 v1710aRobotics1 aBicchi, A.1 aFagiolini, A1 aPallottino, L. uhttp://www.centropiaggio.unipi.it/publications/towards-society-robots-behaviors-misbehaviors-and-security.html00810nas a2200205 4500008004100000024006600041245011000107210006900217260004600286300001400332490001400346653001200360653001300372100001600385700001500401700002000416700001600436700001500452856013700467 2010 eng d aVol. 6192/2012 Lecture Notes in Computer Science, pp. 136-14300aValidation of a Virtual Reality Environment to Study Anticipatory Modulation of Digit Forces and Position0 aValidation of a Virtual Reality Environment to Study Anticipator aAmsterdam (The Netherlands)cJuly, 8 - 10 a136 - 1430 v6192/201010aHaptics10aRobotics1 aBianchi, M.1 aGrioli, G.1 aScilingo, E. P.1 aSantello, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/validation-virtual-reality-environment-study-anticipatory-modulation-digit-forces-and00594nas a2200193 4500008004100000245005100041210005100092260001300143300001400156490000800170653001300178100001800191700001500209700002000224700001500244700002000259700002200279856009900301 2010 eng d00aVisual Servoing via Advanced Numerical Methods0 aVisual Servoing via Advanced Numerical Methods bSpringer a335 - 3600 v40110aRobotics1 aFontanelli, D1 aSalaris, P1 aBelo, F., A. W.1 aBicchi, A.1 aChesi, Graziano1 aHashimoto, Koichi uhttp://www.centropiaggio.unipi.it/publications/visual-servoing-advanced-numerical-methods.html00672nas a2200193 4500008004100000024002000041245007700061210006900138260003000207300001600237653002100253653001300274100002000287700001500307700001400322700001500336700001500351856011200366 2010 eng d app. 3676 - 368100aVSA-HD: From the Enumeration Analysis to the Prototypical Implementation0 aVSAHD From the Enumeration Analysis to the Prototypical Implemen aSt. Louis MO USAcOctober a3676 - 368110aEmbedded Control10aRobotics1 aCatalano, M. G.1 aGrioli, G.1 aBonomo, F1 aSchiavi, R1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/vsa-hd-enumeration-analysis-prototypical-implementation.html01320nas a2200193 4500008004100000245008200041210006900123260004700192300001000239520063700249653002100886653001300907100001400920700001800934700001300952700001600965700001500981856013000996 2009 eng d00aDesigning Real-Time Embedded Controllers using the Anytime Computing Paradigm0 aDesigning RealTime Embedded Controllers using the Anytime Comput aPalma de Mallorca, SpaincSeptember, 12 -  a1 - 83 a

In this paper we present a methodology for designing embedded controllers with a variable accuracy. The adopted paradigm is the so called any-time control, which derives from the computing paradigm known as "imprecise computation". The most relevant contributions of the paper are a procedure for designing an incremental control law, whose different pieces cater for increasingly aggressive control requirements, and a modelling technique for the execution platform that allows us to design provably correct switching policies for the controllers. The methodology is validated by both simulations and experimental results.

10aEmbedded Control10aRobotics1 aQuagli, A1 aFontanelli, D1 aGreco, L1 aPalopoli, L1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/designing-real-time-embedded-controllers-using-anytime-computing-paradigm.html01562nas a2200181 4500008004100000245004900041210004900090260003600139300001200175520099900187653002101186653001301207100001701220700001501237700001501252700001501267856009801282 2009 eng d00aDistributed Consensus on Boolean Information0 aDistributed Consensus on Boolean Information aVenice, ItalycSeptember, 24 -  a72 - 773 a

In this paper we study the convergence towards consensus on information in a distributed system of agents communicating over a network. The particularity of this study is that the information on which the consensus is seeked is not represented by real numbers, rather by logical values or compact sets. Whereas the problems of allowing a network of agents to reach a consensus on logical functions of input events, and that of agreeing on set-valued information, have been separately addressed in previous work, in this paper we show that these problems can indeed be attacked in a unified way in the framework of Boolean distributed information systems. Based on a notion of contractivity for Boolean dynamical systems, a necessary and suficient condition ensuring the global convergence toward a unique equilibrium point is presented. This result can be seen as a first step toward the de nition of a unified framework to uniformly address all consensus problems on Boolean algebras.

10aEmbedded Control10aRobotics1 aFagiolini, A1 aMartini, S1 aDubbini, N1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/distributed-consensus-boolean-information.html00593nas a2200157 4500008004100000245007500041210006900116260003000185300001600215653002100231653001300252100001700265700001500282700001500297856012300312 2009 eng d00aDynamic Distributed Intrusion Detection for Secure Multi-Robot Systems0 aDynamic Distributed Intrusion Detection for Secure MultiRobot Sy aKobe, JapancMay, 12 - 17 a2723 - 272810aEmbedded Control10aRobotics1 aFagiolini, A1 aBabboni, F1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/dynamic-distributed-intrusion-detection-secure-multi-robot-systems.html00615nas a2200157 4500008004100000245009000041210006900131260003000200300001400230653002100244653001300265100001500278700001400293700001500307856013500322 2009 eng d00aIntegration of Active and Passive Compliance Control for Safe Human-Robot Coexistence0 aIntegration of Active and Passive Compliance Control for Safe Hu aKobe, JapancMay, 12 - 17 a259 - 26410aEmbedded Control10aRobotics1 aSchiavi, R1 aFlacco, F1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/integration-active-and-passive-compliance-control-safe-human-robot-coexistence.html00780nas a2200181 4500008004100000245005400041210005100095260004000146300001400186520020700200653001200407653001300419100001600432700001400448700002000462700001500482856010100497 2009 eng d00aA new softness display based on bi-elastic fabric0 anew softness display based on bielastic fabric aSalt Lake City, USAcMarch, 18 - 20 a382 - 3833 a

Haptic perception allows to explore and recognize an object by conveying several physical information to mechano-receptors and thermo-receptors lying into our skin throughout the body. The term

10aHaptics10aRobotics1 aBianchi, M.1 aSerio, A.1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/new-softness-display-based-bi-elastic-fabric.html01817nas a2200193 4500008004100000245012300041210006900164260003900233300001400272520106400286653002101350653004401371653001301415100001601428700001401444700001501458700001501473856013501488 2009 eng d00aNonlinear Decoupled Motion-Stiffness Control and Collision Detection/Reaction for the VSA-II Variable Stiffness Device0 aNonlinear Decoupled MotionStiffness Control and Collision Detect aSt. Louis MO USAcOctober, 11 - 15 a5487-54943 a

Variable Stiffness Actuation (VSA) devices are being used to jointly address the issues of safety and performance in physical human-robot interaction. With reference to the VSA-II prototype, we present a feedback linearization approach that allows the simultaneous decoupling and accurate tracking of motion and stiffness reference profiles. The operative condition that avoids control singularities is characterized. Moreover, a momentum-based collision detection scheme is introduced, which does not require joint torque sensing nor information on the time-varying stiffness of the device. Based on the residual signal, a collision reaction strategy is proposed that takes advantage of the proposed nonlinear control to rapidly let the arm bounce away after detecting the impact, while limiting contact forces through a sudden reduction of the stiffness. Simulations results are presented to illustrate the performance of the overall approach. Extensions to the multi-dof case of robot manipulators equipped with VSA-II devices are also considered.

10aEmbedded Control10aPhysical Human-Robot Interaction (pHRI)10aRobotics1 aDe Luca, A.1 aFlacco, F1 aSchiavi, R1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/nonlinear-decoupled-motion-stiffness-control-and-collision-detectionreaction-vsa-ii00542nas a2200157 4500008004100000245005400041210005300095260004300148653001200191653001300203100001600216700001400232700002000246700001500266856010300281 2009 eng d00aRendering softness: a new fabric yielding display0 aRendering softness a new fabric yielding display aSestri levante (Ge), ItalycDecember 310aHaptics10aRobotics1 aBianchi, M.1 aSerio, A.1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/rendering-softness-new-fabric-yielding-display.html01976nas a2200217 4500008004100000245007200041210006800113260003900181300001400220520126700234653001301501100001501514700002001529700001401549700002001563700001501583700001501598700001701613700001501630856011301645 2009 eng d00aA Rough-Terrain, Casting Robot for the ESA Lunar Robotics Challenge0 aRoughTerrain Casting Robot for the ESA Lunar Robotics Challenge aSt. Louis MO USAcOctober, 11 - 15 a3336-33423 a

This paper describes the design and implementation of DAVID, a lunar vehicle developed for the European Space Agency (ESA) Lunar Robotics Challenge, presenting severe terrain negotiation and sample acquisition challenges. We discuss in some detail two of the main innovative aspects of our entry to the challenge, i.e. the locomotion system and the sample acquisition system. Motivated by the challenge specifications, a range of different locomotion systems were considered, among which we chose a simple, rugged and effective wheeled system. We provide an account of the choice of five different types of wheels, which were designed, analyzed and experimentally tested in conditions similar to the challenge. The system eventually turned out to be very effective in negotiating 89% slopes of volcanic terrain on the challenge site, Mount Teide in Tenerife. To reduce the distance to be traveled on the difficult terrain and avoid risks in reaching the lowest parts of a crater, the vehicle was endowed with an innovative sample acquisition system, i.e. a casting manipulator. Casting manipulation is a technique in which the end-effector is thrown, the sample material is acquired, and the end-effector is retrieved using a light tether that acts as a

10aRobotics1 aAlicino, S1 aCatalano, M. G.1 aBonomo, F1 aBelo, F., A. W.1 aGrioli, G.1 aSchiavi, R1 aFagiolini, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/rough-terrain-casting-robot-esa-lunar-robotics-challenge.html00588nas a2200157 4500008004100000245007600041210006900117260003000186653002100216653001300237100001500250700001700265700001200282700001500294856012100309 2009 eng d00aSafety and Security in Networked Robotics Systems via Logical Consensus0 aSafety and Security in Networked Robotics Systems via Logical Co aMilan, ItalycJuly, 2 - 510aEmbedded Control10aRobotics1 aMartini, S1 aFagiolini, A1 aDini, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/safety-and-security-networked-robotics-systems-logical-consensus.html01495nas a2200169 4500008004100000245004900041210004200090260003700132300001600169520096800185653002101153653001301174100001901187700001501206700001301221856009101234 2009 eng d00aOn the Security of Linear Consensus Networks0 aSecurity of Linear Consensus Networks aShangai, ChinacDecember, 16 - 1 a4894 - 49013 a

The task of performing trustworthy computation in a network of autonomous agents in the presence of misbehaving components is the subject of this work. A solution to this problem is relevant for several coordination, formation, and synchronization tasks. Relying only on the information flow of the control protocol, uncooperative behaviors are revealed using an unknown input observer technique. Necessary and sufficient conditions to detect and correctly identify misbehaving nodes are given, together with a study of the genericity of such conditions. It is shown that generically any node of the network can correctly estimate the state of the other agents, and therefore compute any function of the state, provided that the connectivity of the communication graph is strictly greater than the number of misbehaving nodes. An intrusion detection and identification algorithm is described, and its effectiveness is confirmed through a numerical study.

10aEmbedded Control10aRobotics1 aPasqualetti, F1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/security-linear-consensus-networks.html01150nas a2200169 4500008004100000245006300041210006200104260002900166300001400195520057900209653002100788653001300809100001700822700001500839700001500854856011100869 2009 eng d00aSet-Valued Consensus for Distributed Clock Synchronization0 aSetValued Consensus for Distributed Clock Synchronization aBangalorecAugust, 22-25 a116 - 1213 a

This paper addresses the clock synchronization problem in a wireless sensor network (WSN) and proposes a distributed solution that consists of a form of consensus, where agents are able to exchange data representing intervals or sets. The solution is based on a centralized algorithm for clock synchronization, proposed by Marzullo, that determines the smallest interval that is in common with the maximum number of measured interval. We first show how to convert such an algorithm into a problem involving only operations on sets, and then we convert it into a set

10aEmbedded Control10aRobotics1 aFagiolini, A1 aMartini, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/set-valued-consensus-distributed-clock-synchronization.html01195nas a2200181 4500008004100000245008000041210006900121260003700190300001600227520054900243653002100792653001300813100001900826700001500845700001800860700001500878856012000893 2009 eng d00aShortest Paths for Non-holonomic Vehicles with Limited Field of View Camera0 aShortest Paths for Nonholonomic Vehicles with Limited Field of V aShangai, ChinacDecember, 16 - 1 a8434 - 84393 a

This paper presents a complete characterization of shortest paths for unicycle-like nonholonomic mobile robots equipped with a pinhole camera rigidly fixed with limited Field-Of-View (FOV). We preliminarily provide an alphabet of optimal control words and then we demonstrate how to obtain the partition induced by shortest path in the vehicle plane. The word univocally associated to a region encodes the shortest path from any starting point in that region to the goal point of the mobile robot without violating the FOV constraints.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aSalaris, P1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-non-holonomic-vehicles-limited-field-view-camera.html00680nas a2200205 4500008004100000245006400041210006400105260002300169300001400192490003100206653001300237100001800250700001500268700002000283700001500303700001700318700001400335700001300349856011200362 2009 eng d00aVisual appearance mapping for optimal vision based servoing0 aVisual appearance mapping for optimal vision based servoing bSpringercMarch 28 a353 - 3620 v54 - Experimental Robotics10aRobotics1 aFontanelli, D1 aSalaris, P1 aBelo, F., A. W.1 aBicchi, A.1 aSiciliano, B1 aKhatib, O1 aGroen, F uhttp://www.centropiaggio.unipi.it/publications/visual-appearance-mapping-optimal-vision-based-servoing.html01530nas a2200205 4500008004100000245003300041210003300074260000900107300001400116490000700130520099300137653002101130653001301151100001801164700001401182700002001196700001501216700001501231856007801246 2009 eng d00aVisual Servoing in the Large0 aVisual Servoing in the Large cJune a802 - 8140 v283 a

In this paper we consider the problem of maneuvering an autonomous robot in complex unknown environments using vision. The goal is to accurately servo a wheeled vehicle to a desired posture using only feedback from an on-board camera, taking into account the nonholonomic nature of the vehicle kinematics and the limited field-ofview of the camera. With respect to existing visual servoing schemes, which achieve similar goals locally (i.e. when the desired and actual camera views are sufficiently similar), we propose a method to visually navigate the robot through an extended visual map before eventually reaching the desired goal. The map comprises a set of images, previously stored in an exploratory phase, that convey both topological and metric information regarding the connectivity through feasible robot paths and the geometry of the environment, respectively. Experimental results on a laboratory setup are reported showing the practicality of the proposed approach.

10aEmbedded Control10aRobotics1 aFontanelli, D1 aDanesi, A1 aBelo, F., A. W.1 aSalaris, P1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/visual-servoing-large.html01482nas a2200205 4500008004100000245006200041210006100103260003500164300001400199490001400213520082800227653002101055653001301076100001801089700001301107700001501120700001701135700001401152856011001166 2008 eng d00aAnytime Control Algorithms for Real-Time Embedded Systems0 aAnytime Control Algorithms for RealTime Embedded Systems aSt. Louis, MObSpringer-Verlag a158 - 1710 v4981/20083 a

In this paper we consider the problem of designing controllers for linear plants to be implemented in embedded platforms under stringent real-time constraints. These include preemptive scheduling schemes, under which the maximum execution time allowed for control software tasks is uncertain. We propose an ``anytime control'' design approach, consisting in a hierarchy of controllers for the same plant. Higher controllers in the hierarchy provide better closed-loop performance, while typically requiring a larger worst-case execution time. We provide a procedure for the design of controllers which, together with a conditioning process of the stochastic scheduling, provides better performance than prevailing worst case-based design, while guaranteeing almost sure stability of the resulting switching system.

10aEmbedded Control10aRobotics1 aFontanelli, D1 aGreco, L1 aBicchi, A.1 aEgerstedt, M1 aMishra, B uhttp://www.centropiaggio.unipi.it/publications/anytime-control-algorithms-real-time-embedded-systems.html01635nas a2200181 4500008004100000245007600041210006900117300001400186520101800200653002101218653001301239100001701252700001801269700001501287700001201302700001501314856012401329 2008 eng d00aConsensus-based Distributed Intrusion Detection for Multi-Robot Systems0 aConsensusbased Distributed Intrusion Detection for MultiRobot Sy a120 - 1273 a

This paper addresses a security problem in robotic multi-agent systems, where agents are supposed to cooperate according to a shared protocol. A distributed Intrusion Detection System (IDS) is proposed here, that detects possible non- cooperative agents. Previous work by the authors showed how single monitors embedded on-board the agents can detect non- cooperative behavior, using only locally available information. In this paper, we allow such monitors to share the collected information in order to overcome their sensing limitation. In this perspective, we show how an agreement on the type of behavior of a target-robot may be reached by the monitors, through execution of a suitable consensus algorithm. After formulating a consensus problem over non-scalar quantities, and with a generic update function, we provide conditions for the consensus convergence and an upper bound to its transient duration. Effectiveness of the proposed solution is finally shown through simulation of a case study.

10aEmbedded Control10aRobotics1 aFagiolini, A1 aPellinacci, M1 aValenti, M1 aDini, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/consensus-based-distributed-intrusion-detection-multi-robot-systems.html00562nas a2200145 4500008004100000245008000041210006900121300001600190653002100206653001300227100001500240700001700255700001500272856012900287 2008 eng d00aControllability Decompositions of Networked Systems Through Quotient Graphs0 aControllability Decompositions of Networked Systems Through Quot a5244 - 524910aEmbedded Control10aRobotics1 aMartini, S1 aEgerstedt, M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllability-decompositions-networked-systems-through-quotient-graphs.html01034nas a2200193 4500008004100000245008600041210006900127260003300196300001400229490001400243520044200257653002100699653001300720100001700733700001200750700001500762700001200777856005100789 2008 eng d00aDecentralized Deployment of Mobile Sensors for Optimal Connected Sensing Coverage0 aDecentralized Deployment of Mobile Sensors for Optimal Connected bSpringer Berlin / Heidelberg a486 - 4910 v5067/20083 a

In this paper, we address the optimal connected sensing coverage problem, i.e., how mobile sensors with limited sensing capabilities can cooperatively adjust their locations so as to maximize the extension of the covered area while avoiding any internal "holes", areas that are not covered by any sensor. Our solution consists in a distributed motion algorithm that is based on an original extension of the Voronoi tessellation.

10aEmbedded Control10aRobotics1 aFagiolini, A1 aTani, L1 aBicchi, A.1 aDini, G uhttp://dx.doi.org/10.1007/978-3-540-69170-9_3400518nas a2200133 4500008004100000245007200041210006900113300001600182653002100198653001300219100001600232700001500248856012100263 2008 eng d00aDelay compensation in packet-switching networked controlled systems0 aDelay compensation in packetswitching networked controlled syste a3620 - 362510aEmbedded Control10aRobotics1 aChaillet, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/delay-compensation-packet-switching-networked-controlled-systems.html00511nas a2200193 4500008004100000245004500041210004500086300001200131490000700143653001300150100001500163700001400178700001200192700001600204700001900220700001600239700001500255856004700270 2008 eng d00aHeterogeneous Wireless Multirobot System0 aHeterogeneous Wireless Multirobot System a62–700 v1510aRobotics1 aBicchi, A.1 aDanesi, A1 aDini, G1 aLa Porta, S1 aPallottino, L.1 aSavino, I M1 aSchiavi, R uhttp://dx.doi.org/10.1109/M-RA.2007.91492500458nas a2200157 4500008004100000245002800041210002800069300001300097653002100110653001300131100001300144700003200157700001600189700001500205856008000220 2008 eng d00aHybrid system reduction0 aHybrid system reduction a227 -23210aEmbedded Control10aRobotics1 aMazzi, E1 aVincentelli, Sangiovanni, A1 aBalluchi, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/hybrid-system-reduction.html01573nas a2200145 4500008004100000245011000041210006900151300001200220520099600232653002101228653001301249100001501262700001501277856013501292 2008 eng d00aHypercubes are minimal controlled invariants for discrete-time linear systems with quantized scalar input0 aHypercubes are minimal controlled invariants for discretetime li a706-7203 a

Quantized linear systems are a widely studied class of nonlinear dynamics resulting from the control of a linear system through finite inputs. The stabilization problem for these models shall be studied in terms of the so called practical stability notion that essentially consists in confining the trajectories into sufficiently small neighborhoods of the equilibrium (ultimate boundedness) . In this paper, we study the problem of describing the smallest sets into which any feedback can ultimately confine the state, for a given linear single-input system with an assigned finite set of admissible input values (quantization). We show that a controlled invariant set of minimal size is contained in a family of sets (namely, hypercubes in controller-canonical form), previously introduced in [14, 15] . A comparison is presented which quantifies the improvement in tightness of the proposed analysis technique with respect to classical results using quadratic Lyapunov functions.

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/hypercubes-are-minimal-controlled-invariants-discrete-time-linear-systems-quantized01875nas a2200157 4500008004100000245008300041210006900124300001600193520130000209653002101509653001301530100001501543700001501558700001501573856012901588 2008 eng d00aLeft invertibility of discrete systems with finite inputs and quantized output0 aLeft invertibility of discrete systems with finite inputs and qu a4687 - 46923 a

The aim of this paper is to address left invertibility for dynamical systems with inputs and outputs in discrete sets. We study systems that evolve in discrete time within a continuous state-space. Quantized outputs are generated by the system according to a given partition of the state-space, while inputs are arbitrary sequences of symbols in a finite alphabet, which are associated to specific actions on the system. We restrict to the case of contractive dynamics for fixed inputs. The problem of left invertibility, i.e. recovering an unknown input sequence from the knowledge of the corresponding output string, is addressed using the theory of Iterated Function Systems (IFS), a tool developed for the study of fractals. We show how the IFS naturally associated to a system and the geometric properties of its attractor are linked to the left invertibility property of the system. Our main results are a necessary and sufficient condition for a given system to be left invertible with probability one on the space of inputs (i.e. for almost all input sequences), and necessary and sufficient conditions for left invertibility and uniform left invertibility under some weak additional hypotheses. A few examples are presented to illustrate the application of the proposed method.

10aEmbedded Control10aRobotics1 aDubbini, N1 aPiccoli, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/left-invertibility-discrete-systems-finite-inputs-and-quantized-output.html-000504nas a2200145 4500008004100000245005600041210005600097300001600153653002100169653001300190100001700203700001900220700001500239856010400254 2008 eng d00aLogical Consensus for Distributed Network Agreement0 aLogical Consensus for Distributed Network Agreement a5250 - 525510aEmbedded Control10aRobotics1 aFagiolini, A1 aVisibelli, E M1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/logical-consensus-distributed-network-agreement.html00432nas a2200121 4500008004100000245005700041210005500098300001000153653001200163653001300175100001500188856010700203 2008 eng d00aMacchine e Mani: Immagini, Immaginazione e Creazione0 aMacchine e Mani Immagini Immaginazione e Creazione a13-2110aHaptics10aRobotics1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/macchine-e-mani-immagini-immaginazione-e-creazione.html01569nas a2200157 4500008004100000245008300041210006900124300001600193520099700209653002101206653001301227100001101240700001601251700001501267856012901282 2008 eng d00aNeural network based robust adaptive control for a variable stiffness actuator0 aNeural network based robust adaptive control for a variable stif a1028 - 10343 a

In this paper we present a robust adaptive controller based on a neural network (NN) for a variable stiffness actuator (VSA). The controller is able to independently set the mechanical stiffness and position at the joint shaft to guarantee robustness with respect to slowly time-varying and unmodeled friction coefficients affecting the dynamics of the actuator. The lumped uncertainties of the VSA including unmodeled dynamics are considered and approximated by a simple NN so that the controlled system is asymptotically stable, and remains effective while process conditions vary. To cope with the reconstruction error of the NN, a sliding mode like additional robust control term is introduced. The proofs for the uniformly ultimately bounded (UUB) and uniform asymptotic (UAS) stabilities for the closed-loop system are provided in detail via Lyapunov theory. Simulation and experimental results are reported in support of both validity and performance of the proposed approach.

10aEmbedded Control10aRobotics1 aHuh, S1 aTonietti, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/neural-network-based-robust-adaptive-control-variable-stiffness-actuator.html01496nas a2200181 4500008004100000245007800041210006900119260001500188300001400203520088200217653001301099100001501112700002001127700001801147700001301165700001501178856012101193 2008 eng d00aOptimal Paths in a Constrained Image Plane for Purely Image-Based Parking0 aOptimal Paths in a Constrained Image Plane for Purely ImageBased c22-26 Sept a1673-16803 a

This paper presents a correct solution to the optimal feedback control for a nonholonomic vehicle with limited field-of-view. Previous work on this subject has shown that the search for a shortest path can be limited to simple families of trajectories. We preliminarily provide an extension of the alphabet of optimal control words, to cover some regions of the vehicle plane where the synthesis of turns out to be suboptimal. The main contribution of this paper is an algorithm to translate the optimal synthesis to the image plane, thus enabling a purely image-based optimal control scheme. This allows better performance and increases the robustness of the overall process, avoiding the need of slowly-converging and error-prone parameter estimation algorithms. Simulations and experiments are reported which demonstrate the effectiveness of the proposed technique.

10aRobotics1 aSalaris, P1 aBelo, F., A. W.1 aFontanelli, D1 aGreco, L1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-paths-constrained-image-plane-purely-image-based-parking.html01584nas a2200265 4500008004100000245007700041210006900118300000900187520075100196653002100947653004400968653001301012100001501025700001401040700001701054700001701071700001701088700001501105700001801120700001201138700001501150700001101165700001601176856012601192 2008 eng d00aPhysical Human-Robot Interaction: Dependability, Safety, and Performance0 aPhysical HumanRobot Interaction Dependability Safety and Perform a9-143 a

In this paper we discuss the problem of achieving good performance in accuracy and promptness by a robot manipulator under the condition that safety is guaranteed throughout task execution. Intuitively, while a rigid and powerful structure of the arm would favor its performance, lightweight compliant structures are more suitable for safe operation. The quantitative analysis of the resulting design trade-off between safety and performance has a strong impact on how robot mechanisms and controllers should be designed for human-interactive applications. We discuss few different possible concepts for safely actuating joints, and focus on aspects related to the implementation of the mechanics and control of this new class of robots.

10aEmbedded Control10aPhysical Human-Robot Interaction (pHRI)10aRobotics1 aBicchi, A.1 aBavaro, M1 aBoccadamo, G1 aCarli, De, D1 aFilippini, R1 aGrioli, G.1 aPiccigallo, M1 aRosi, A1 aSchiavi, R1 aSen, S1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/physical-human-robot-interaction-dependability-safety-and-performance.html00731nas a2200145 4500008004100000245009200041210006900133300001400202520017500216653001300391100001800404700001300422700001500435856013500450 2008 eng d00aRobust Almost Sure Stability for Uncertain Stochastically Scheduled Anytime Controllers0 aRobust Almost Sure Stability for Uncertain Stochastically Schedu a249 - 2543 a

In this paper we consider closed loop stability of a number of different software tasks implementing a hierarchy of real-time controllers for a given plant, i.e.

10aRobotics1 aFontanelli, D1 aGreco, L1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/robust-almost-sure-stability-uncertain-stochastically-scheduled-anytime-controllers04318nas a2200181 4500008004100000245007300041210006800114260003300182490001200215520371700227653001203944653001303956100001503969700001203984700001403996700001204010856011404022 2008 eng d00aThe Sense of Touch and its Rendering: Progresses in Haptics Research0 aSense of Touch and its Rendering Progresses in Haptics Research aBerlin, HeidelbergbSpringer0 v45/20083 a

Preface: It is no coincidence that in many languages, deeply involving emotions and feelings are described as "touching". Touch appears indeed to be the most direct, less intellectually mediated sense. As such, it should be a fundamental ingredient of any system aimed at providing compelling sensations of remote presence. Generation of high-definition haptic feedback will be crucially important for driving a sense of Presence in next generation immersive VR and teleoperation systems. The perspective in which this book is conceived is that of understanding and enabling an experience of presence not limited to "being there", but extended to "being in touch" with the virtual or remote surroundings. Despite of numerous technological advances in this field it appears that the development of fully immersive haptic displays cannot proceed by technological innovations alone but requires a deep understanding and utilization of the psychophysical mechanisms of human haptic perception. On one hand, technological innovations are needed to increase the richness and accuracy of physically generated haptic stimuli. The generation of a one-to-one copy of the real world seems, however, to be unfeasible due to the inherent complexity of the necessary devices and stringent physiological and mechanical constraints. On the other hand, advances in the understanding of the information processing of the multidimensional sense of touch contribute to overcome these fundamental technological constraints. Limitations of the human perceptual system can be exploited to provide a realistic haptic sensation without getting all the physical parameters completely right. Perceptual limitations already helped in the design of advanced visual and auditory displays. This book summarizes main results of the TOUCH-HapSys research project financially supported by the 5th Framework IST Programme of the European Union. It provides an important contribution towards a new generation of high-fidelity haptic display technologies. The uniqueness of this book is its interdisciplinary approach highlighting the field of haptic research from a neuropsychological as well as a technological point of view. It provides readers with recent advances in the study of human haptic (kinesthetic, tactile, temperature) and mul-timodal (visual, auditory, haptic) perception mechanisms and with innovations in the field of haptic display technology. It shows that both lines of research are intimately connected, not only because biological sciences inspire and enable technology improvement, but also because novel devices offer new facilities for the experimental testing of psychophysical hypotheses. This book is structured in two parts: A. Fundamental Psychophysical and Neuropsychological Research and B. Technology and Applications. Chapters in part A. concentrate on the study of the basic mechanisms of touch, involving neurophysiology, psychophysics, and functional mappings in the brain. In-depth study of the psychophysiology of the sense of touch establishes connections between haptic fundamental perception and virtual-reality oriented technology. Part B. addresses new technologies to significantly improve haptic and multimodal feedback systems. These include novel actuator designs, software solutions for haptic rendering, and applications. The two parts are not however separated, and the many connections and synergies between the two complementary domains of research are highlighted in the text. Finally the editors would like to thank all the authors for their valuable contributions to this book. The quality and freshness found in each chapter are due to the excellent work carried out by the authors.

10aHaptics10aRobotics1 aBicchi, A.1 aBuss, M1 aErnst, M.1 aPeer, A uhttp://www.centropiaggio.unipi.it/publications/sense-touch-and-its-rendering-progresses-haptics-research.html01613nas a2200229 4500008004100000245007300041210006800114260003300182300001200215490001200227520089600239653001201135653001301147100002001160700001901180700001501199700001501214700001201229700001401241700001201255856011601267 2008 eng d00aThe Sense of Touch and its Rendering: Progresses in Haptics Research0 aSense of Touch and its Rendering Progresses in Haptics Research aBerlin, HeidelbergbSpringer a39 - 600 v45/20083 a

Dynamic stimuli in visual and tactile sensory modalities share fundamental psychophysical features that can be explained by similar computational models. In vision, information about relative motion between objects and the observer are mainly processed by optic flow, which is a 2D field of velocities associated with variation of brightness patterns in the image plane. It provides important information about cues for region and boundary segmentation, shape recovery, and so on. For instance, radial patterns of optic flow are often used to estimate time before contact with an approaching object. We put forward the hypothesis that a similar behavior can be present in the tactile domain, in which an analogous paradigm to optic flow might exist. Moreover, as optic flow is also invoked to explain several visual illusions, including the well-known "barber-pole" effect and Ouchi

10aHaptics10aRobotics1 aScilingo, E. P.1 aSgambelluri, N1 aBicchi, A.1 aBicchi, A.1 aBuss, M1 aErnst, M.1 aPeer, A uhttp://www.centropiaggio.unipi.it/publications/sense-touch-and-its-rendering-progresses-haptics-research.html-001547nas a2200241 4500008004100000245007300041210006800114260003300182300001200215490001200227520080500239653001201044653001301056100001901069700002001088700001301108700001501121700001501136700001201151700001401163700001201177856011601189 2008 eng d00aThe Sense of Touch and its Rendering: Progresses in Haptics Research0 aSense of Touch and its Rendering Progresses in Haptics Research aBerlin, HeidelbergbSpringer a155-1780 v45/20083 a

In this work we investigate the possibility of mimicking haptic perception by using rheological materials. An analysis of the rheological behaviour of some "smart fluids", such as Electro-rheological Fluids (ERFs) and Magneto-rheological Fluids (MRFs), is provided to design new haptic interfaces capable of reproducing shape and compliance of some virtual objects. Some theoretical design considerations are discussed and supported by magnetic simulations implemented by means of a numerical code. Several prototypes were designed and realized through a progressive enhancement of performance up to a final 3D immersive device. Furthermore, to assess performance a set of psychophysical tests was carried out and experimental results in terms of softness and shape recognition are reported.

10aHaptics10aRobotics1 aSgambelluri, N1 aScilingo, E. P.1 aRizzo, R1 aBicchi, A.1 aBicchi, A.1 aBuss, M1 aErnst, M.1 aPeer, A uhttp://www.centropiaggio.unipi.it/publications/sense-touch-and-its-rendering-progresses-haptics-research.html-102165nas a2200337 4500008004100000245010800041210006900149300001200218490000700230520114700237653001201384653001301396100001501409700001501424700001501439700001701454700001701471700001401488700001501502700001501517700001901532700002001551700001901571700001601590700002201606700001501628700001601643700001701659700001501676856013601691 2008 eng d00aSensing Glove for Brain Studies: Design and assessment of its Compatibility for fMRI with a Robust Test0 aSensing Glove for Brain Studies Design and assessment of its Com a345-3540 v133 a

In this paper, we describe a biomimetic-fabric-based sensing glove that can be used tomonitor hand posture and gesture. Our device is made of a distributed sensor network of piezoresistive conductive elastomers integrated into an elastic fabric. This solution does not affect natural movement and hand gestures, and can be worn for a long time with no discomfort. The glove could be fruitfully employed in behavioral and functional studies with functional MRI (fMRI) during specific tactile or motor tasks. To assess MR compatibility of the system, a statistical test on phantoms is introduced. This test can also be used for testing the compatibility of mechatronic devices designed to produce different stimuli inside the MR environment. We propose a statistical test to evaluate changes in SNR and time-domain standard deviations between image sequences acquired under different experimental conditions. fMRI experiments on subjects wearing the glove are reported. The reproducibility of fMRIresults obtained with andwithout the glove was estimated. A good similarity between the activated regions was found in the two conditions.

10aHaptics10aRobotics1 aVanello, N1 aHartwig, V1 aTesconi, M1 aRicciardi, E1 aTognetti, A.1 aZupone, G1 aGassert, R1 aChapuis, D1 aSgambelluri, N1 aScilingo, E. P.1 aGiovannetti, G1 aPositano, V1 aSantarelli, M. F.1 aBicchi, A.1 aPietrini, P1 aDe Rossi, D.1 aLandini, L uhttp://www.centropiaggio.unipi.it/publications/sensing-glove-brain-studies-design-and-assessment-its-compatibility-fmri-robust-test01102nas a2200205 4500008004100000245005700041210005600098260002000154300001200174490001400186520047900200653002100679653001300700100001900713700001500732700001500747700001700762700001400779856010300793 2008 eng d00aSteering a Leader-Follower Team via Linear Consensus0 aSteering a LeaderFollower Team via Linear Consensus bSpringer-Verlag a642-6450 v4981/20083 a

The paper considers the problem of driving a formation of autonomous mobile agents. The group of mobile devices is described as a leader–follower network, where the followers update their position using a simple local consensus procedure, while the leaders, whose positions represent the control inputs of the network, are free to move. We characterize the transient behavior of the network, and solve the containment problem without relying on auxiliary sensors.

10aEmbedded Control10aRobotics1 aPasqualetti, F1 aMartini, S1 aBicchi, A.1 aEgerstedt, M1 aMishra, B uhttp://www.centropiaggio.unipi.it/publications/steering-leader-follower-team-linear-consensus.html02206nas a2200193 4500008004100000245007300041210006900114260001300183300001200196490000700208520158200215653001201797653001301809100001501822700002001837700001701857700001601874856012201890 2008 eng d00aTactile flow explains haptic counterparts of common visual illusions0 aTactile flow explains haptic counterparts of common visual illus cApril 15 a737-7410 v753 a

Interaction with the external world requires the ability to perceive dynamic changes in complex sensorial input and react promptly. Here we show that perception of dynamic stimuli in the visual and tactile sensory modalities share fundamental psychophysical aspects that can be explained by similar computational models. In vision, optic flow provides information on relative motion between the individual and the content of percept. For instance, radial patterns of optic flow are used to estimate time before contact with an approaching object4. Similarly, in the tactile modality, radial patterns of stimuli provide information on softness of probed objects3. Optic flow is also invoked to explain several visual illusions, including the well-known "barber-pole" effect10. Here we introduce a computational model of tactile flow, which is intimately related to existing models for the visual counterpart. The model accounts for psychophysical aspects of dynamic tactile perception and predicts illusory phenomena in the tactile domain, analogous to the barber-pole effect. When subjects touched translating pads with differently oriented gratings, they perceived a direction of motion that was significantly biased towards the orientation of the gratings. Therefore, these findings indicate that visual and tactile flow share similarities at the psychophysical and computational level and may be intended for similar perceptive goals. Results of this analysis have impact on the engineering of better haptic and multimodal interfaces for human-computer interaction.

10aHaptics10aRobotics1 aBicchi, A.1 aScilingo, E. P.1 aRicciardi, E1 aPietrini, P uhttp://www.centropiaggio.unipi.it/publications/tactile-flow-explains-haptic-counterparts-common-visual-illusions.html00619nas a2200169 4500008004100000245006600041210006600107260005300173300001400226653002100240653001300261100001700274700001500291700001200306700001600318856011500334 2008 eng d00aTolerating Malicious Monitors in Detecting Misbehaving Robots0 aTolerating Malicious Monitors in Detecting Misbehaving Robots aTohoku University Aobayama Campus, Sendai, Japan a108 - 11410aEmbedded Control10aRobotics1 aFagiolini, A1 aBicchi, A.1 aDini, G1 aSavino, I M uhttp://www.centropiaggio.unipi.it/publications/tolerating-malicious-monitors-detecting-misbehaving-robots.html00464nas a2200157 4500008004100000245004000041210004000081300001200121490000700133653002100140653001300161100001700174700001100191700001500202856008900217 2008 eng d00aToward Soft Robot you can Depend on0 aToward Soft Robot you can Depend on a31 - 410 v1510aEmbedded Control10aRobotics1 aFilippini, R1 aSen, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/toward-soft-robot-you-can-depend.html00464nas a2200157 4500008004100000245003400041210003400075260003300109300001400142490000700156653001300163100001400176700001800190700001500208856008300223 2008 eng d00aVisual Servoing on Image Maps0 aVisual Servoing on Image Maps bSpringer Berlin / Heidelberg a277 - 2860 v3910aRobotics1 aDanesi, A1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/visual-servoing-image-maps.html00581nas a2200169 4500008004100000245006700041210006700108300001200175490001200187653001300199100001500212700002000227700001800247700001500265700002000280856011100300 2008 eng d00aVisual SLAM for Servoing for Appearance Based Topological Maps0 aVisual SLAM for Servoing for Appearance Based Topological Maps a277-2860 v39/200810aRobotics1 aSalaris, P1 aBelo, F., A. W.1 aFontanelli, D1 aBicchi, A.1 aSpringer-Verlag uhttp://www.centropiaggio.unipi.it/publications/visual-slam-servoing-appearance-based-topological-maps.html01822nas a2200157 4500008004100000245011600041210006900157300001600226520122400242653001301466100001501479700001501494700001101509700001501520856012901535 2008 eng d00aVSA-II: A Novel Prototype of Variable Stiffness Actuator for Safe and Performing Robots Interacting with Humans0 aVSAII A Novel Prototype of Variable Stiffness Actuator for Safe  a2171 - 21763 a

This paper presents design and performance of a novel joint based actuator for a robot run by variable stiffness actuation, meant for systems physically interacting with humans. This new actuator prototype (VSA-II) is developed as an improvement over our previously developed one reported in [9], where an optimal mechanical-control co-design principle established in [7] is followed as well. While the first version was built in a way to demonstrate effectiveness of variable impedance actuation (VIA), it had limitations in torque capacities, life cycle and implementability in a real robot. VSA-II overcomes the problem of implementability with higher capacities and robustness in design for longer life. The paper discusses design and stiffness behaviour of VSA-II in theory and experiments. A comparison of stiffness characteristics between the two actuator is discussed, highlighting the advantages of the new design. A simple, but effective PD scheme is employed to independently control joint-stiffness and joint-position of a 1-link arm. Finally, results from performed impact tests of 1- link arm are reported, showing the effectiveness of stiffness variation in controlling value of a safety metric.

10aRobotics1 aSchiavi, R1 aGrioli, G.1 aSen, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/vsa-ii-novel-prototype-variable-stiffness-actuator-safe-and-performing-robots01487nas a2200169 4500008004100000245007500041210006900116260001300185300001400198520090500212653002101117653001301138100001301151700001801164700001501182856012001197 2007 eng d00aAlmost Sure Stability of Anytime Controllers via Stochastic Scheduling0 aAlmost Sure Stability of Anytime Controllers via Stochastic Sche cDecember a5640-56453 a

In this paper we consider scheduling the execution of a number of different software tasks implementing a hierarchy of real-time controllers for a given plant. Controllers are considered to be given and ordered according to a measure of the performance they provide. Software tasks implementing higher-performance controllers are assumed to require a larger worst-case execution time. Control tasks are to be scheduled within given availability limits on execution time, which change stochastically in time. The ensuing switching system is prone to instability, unless a very conservative policy is enforced of always using the simplest, least performant controller. The presented method allows to condition the stochastic scheduling of control tasks so as to obtain a better exploitation of computing capabilities, while guaranteeing almost sure stability of the resulting switching system.

10aEmbedded Control10aRobotics1 aGreco, L1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/almost-sure-stability-anytime-controllers-stochastic-scheduling.html00907nas a2200181 4500008004100000245004900041210004500090300001200135490000700147520035500154653004400509653001300553100001700566700001700583700001500600700001500615856009500630 2007 eng d00aAn atlas of physical human-robot interaction0 aatlas of physical humanrobot interaction a253-2700 v433 a

A broad spectrum of issues have to be addressed in order to tackle the problem of a safe and dependable physical Human-Robot Interaction (pHRI). In the immediate future, metrics related to safety and dependability have to be found in order to successfully introduce robots in everyday enviornments. While there are certainly also ``cognitive

10aPhysical Human-Robot Interaction (pHRI)10aRobotics1 aDe Santis, A1 aSiciliano, B1 aLuca, A.De1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/atlas-physical-human-robot-interaction.html01564nas a2200157 4500008004100000245010800041210006900149300001600218520096100234653001301195100001701208700001101225700001601236700001501252856013901267 2007 eng d00aA Comparative Dependability Analysis of Antagonistic Actuation Arrangements for Enhanced Robotic Safety0 aComparative Dependability Analysis of Antagonistic Actuation Arr a4349–43543 aIn this paper we introduce an analysis of dependability of an elementary yet critical component of robotic systems designed to operate in environments shared with humans, i.e. the joint-level actuation system. We consider robot joints that implement the Variable Impedance Actuation (VIA) paradigm. The VIA has been demonstrated to be an effective mean to achieve high performance while constantly keeping injury risks to humans by accidental impacts below a given threshold. The paper describe possible implementations of the VIA concept which use the Antagonistic Actuation (AA) in three different arrangements. This study follows a previously reported paper dealing with safety. Here a detailed comparative dependability and performability analysis in front of possible specific failure modes is conducted, whose results provide additional and useful guidelines for design of safe and dependable actuation systems for physical human-robot interaction. 10aRobotics1 aFilippini, R1 aSen, S1 aTonietti, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/comparative-dependability-analysis-antagonistic-actuation-arrangements-enhanced-robotic01224nas a2200217 4500008004100000245010200041210006900143260000900212300001400221520049500235653002100730653001300751100001700764700001300781700001700794700001500811700001400826700001500840700001900855856013200874 2007 eng d00aA Component-Based Approach to Localization and Collision Avoidance for Mobile Multi-Agent Systems0 aComponentBased Approach to Localization and Collision Avoidance  cJuly a4285-42923 a

In the RUNES project a disaster relief tunnel scenario is being developed in which mobile robots are used to restore the radio network connectivity in a stationary sensor network. A component-based software development approach has been adopted. Two components are described in this paper. A localization component that uses ultrasound and dead reckoning to decide the robot positions and a collision avoidance component that ensures that the robots do not collide with each other.

10aEmbedded Control10aRobotics1 aAlriksson, P1 aNordh, J1 aArzén, K -E1 aBicchi, A.1 aDanesi, A1 aSchiavi, R1 aPallottino, L. uhttp://www.centropiaggio.unipi.it/publications/component-based-approach-localization-and-collision-avoidance-mobile-multi-agent02022nas a2200217 4500008004100000245007400041210006900115300001200184490000700196520134900203653002101552653001301573100001701586700001501603700001201618700001401630700001901644700001501663700001201678856011401690 2007 eng d00aA component-based approach to the design of networked control systems0 acomponentbased approach to the design of networked control syste a261-2790 v133 a

Component-based techniques revolve around composable, reusable software objects that shield the application level software from the details of the hardware and lowlevel software implementation and vice versa. Components provide many benefits that have led to their wide adoption in software and middleware developed for embedded systems: They are well-defined entities that can be replaced without affecting the rest of the systems, they can be developed and tested separately and integrated later, and they are reusable. Clearly such features are important for the design of large-scale complex systems more generally, beyond software architectures. We propose the use of a component approach to address embedded control problems. We outline a general componentbased framework to embedded control and show how it can be instantiated in specific problems that arise in the control over/of sensor networks. Building on the middleware component framework developed under the European project RUNES, we develop a number of control-oriented components necessary for the implementation of control applications and design their integration. The paper provides the overview of the approach, discusses a real life application where the approach has been tested and outlines a number of specific control problems that arise in this application.

10aEmbedded Control10aRobotics1 aArzén, K -E1 aBicchi, A.1 aDini, G1 aHailes, S1 aJohansson, K H1 aLygeros, J1 aTzes, A uhttp://www.centropiaggio.unipi.it/publications/component-based-approach-design-networked-control-systems.html02131nas a2200181 4500008004100000245008600041210006900127300001400196490000700210520150000217653002101717653001301738100001901751700001701770700001601787700001501803856013101818 2007 eng d00aDecentralized cooperative policy for conflict resolution in multi-vehicle systems0 aDecentralized cooperative policy for conflict resolution in mult a1170-11830 v233 a

In this paper we propose a novel policy for steering multiple vehicles between assigned independent start and goal configurations and ensuring collision avoidance. The policy rests on the assumption that agents are all cooperating by implementing the same traffic rules. However, the policy is completely decentralized, as each agent decides its own motion by applying those rules only on locally available information, and totally scalable, in the sense that the amount of information processed by each agent and the computational complexity of the algorithms are not increasing with the number of agents in the scenario. The proposed policy applies to systems in which new vehicle may enter the scene and start interacting with existing ones at any time, while others may leave. Under mild conditions on the initial configurations, the policy is shown to be safe, i.e. to guarantee collision avoidance throughout the system evolution. In the paper, conditions are discussed on the desired configurations of agents under which the ultimate convergence of all vehicles to their goals can also be guaranteed. To show that such conditions are actually necessary and sufficient, which turns out to be a challenging liveness verification problem for a complex hybrid automaton, we employ a probabilistic verification method. The paper finally reports on simulations for systems of several tens of vehicles, and with some experimental implementation showing the practicality of the approach.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aScordio, V G1 aFrazzoli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-cooperative-policy-conflict-resolution-multi-vehicle-systems.html00841nas a2200181 4500008004100000245008100041210006900122300001400191520021300205653002100418653001300439100001700452700001500469700001900484700001200503700001500515856012900530 2007 eng d00aDecentralized Intrusion Detection for Secure Cooperative Multi-Agent Systems0 aDecentralized Intrusion Detection for Secure Cooperative MultiAg a1553-15583 a

In this paper we address the problem of detecting faulty behaviors of cooperative mobile agents. A novel decentralized and scalable architecture that can be adopted to realize a monitor of the agents

10aEmbedded Control10aRobotics1 aFagiolini, A1 aValenti, G1 aPallottino, L.1 aDini, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-intrusion-detection-secure-cooperative-multi-agent-systems.html01344nas a2200169 4500008004100000245007000041210006900111260001300180300001400193520076800207653002100975653001300996100001901009700001501028700001301043856011801056 2007 eng d00aDistributed intrusion detection for secure consensus computations0 aDistributed intrusion detection for secure consensus computation cDecember a5594-55993 a

This paper focuses on trustworthy computation systems and proposes a novel intrusion detection scheme for averaging networks with misbehaving nodes. This prototypical control problem is relevant in network security applications. The objective is for each node to detect and isolate the misbehaving nodes using only the information flow adopted by standard averaging protocols. We focus on the single misbehaving node problem. Our technical approach is based on the theory of Unknown Input Observability. First, we give necessary and sufficient conditions for the misbehavior to be observable and for the identity of the faulty node to be detectable. Second, we design a distributed unknown input estimator, and we characterize its convergence rate in the

10aEmbedded Control10aRobotics1 aPasqualetti, F1 aBicchi, A.1 aBullo, F uhttp://www.centropiaggio.unipi.it/publications/distributed-intrusion-detection-secure-consensus-computations.html01142nas a2200145 4500008004100000245008200041210006900123300001600192520060000208653002100808653001300829100001900842700001500861856012000876 2007 eng d00aA Dynamic Programming Approach to Optimal Planning for Vehicles with Trailers0 aDynamic Programming Approach to Optimal Planning for Vehicles wi a3098 - 31033 a

In this paper we deal with the optimal feedback synthesis problem for robotic vehicles with trailers which can be modeled by differential equations in chained-form. With respect to classical methods for numerical evolution of optimal feedback synthesis via Dynamic Programming which are based on both input and state discretization, our method exploits the lattice structure naturally imposed on the reachable set by input quantization. A generalized Dijkstra algorithm can be used to obtain optimal feedback control laws, for chained-form vehicles with n-trailers, in an effective way.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/dynamic-programming-approach-optimal-planning-vehicles-trailers.html01199nas a2200145 4500008004100000245008200041210006900123260002700192520064800219653001300867100001500880700001900895700001500914856012400929 2007 eng d00aAn experimental study of exploiting multipath fading for robot communications0 aexperimental study of exploiting multipath fading for robot comm aAtlanta, GA, USAcJune3 a

A simple approach for mobile robots to exploit multipath fading in order to improve received radio signal strength (RSS), is presented. The strategy is to sample the RSS at discrete points, without deviating too far from the desired position. We first solve the problem of how many samples are needed for given communications performance and how they should be spaced. Second, we propose a circular and a grid trajectory for sampling and give lower bounds on how many samples they will yield. Third, we estimate the parameters of our strategy from measurements. Finally we demonstrate the validity of our analysis through experiments.

10aRobotics1 aLindhè, M1 aJohansson, K H1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/experimental-study-exploiting-multipath-fading-robot-communications.html01762nas a2200181 4500008004100000245004900041210004700090300001000137520121700147653002101364653001301385100001601398700001501414700001301429700003101442700001301473856009401486 2007 eng d00aHybrid Multi-rate Control of the Common-Rail0 aHybrid Multirate Control of the CommonRail a54-613 a

We present an industrial case study in automotive control of significant complexity: the new common-rail fuel- injection system for Diesel engines developed by Magneti Marelli Powertrain. In this system, an inlet metering valve, inserted before the High Pressure (HP) pump, regulates the fuel flow that supplies the common rail according to the engine operating point (e.g. engine speed and torque). The standard approach to controller design adopted in the automotive in- dustry is based on mean-value models of the plant. However, the fuel injection system exhibits complex discrete-continuous interactions, due to the slow time-varying frequency of the HP pump cycles and the fast sampling frequency of sensing and actuation. Hence, a hybrid approach to controller design is very promising. In this paper, we present the synthesis of a hybrid multi-rate controller for a Magneti Marelli Powertrain common-rail fuel- injection system for four-cylinder multi-jet engines. Controller design is based on a hybrid model of the injection system. The resulting hybrid controller performs significantly better then previous controllers developed in the company on the basis of mean-value models of the plant.

10aEmbedded Control10aRobotics1 aBalluchi, A1 aBicchi, A.1 aMazzi, E1 aSangiovanni-Vincentelli, A1 aSerra, G uhttp://www.centropiaggio.unipi.it/publications/hybrid-multi-rate-control-common-rail.html01037nas a2200181 4500008004100000245010100041210006900142300001400211520038500225653002100610653001300631100001700644700001500661700001900676700001200695700001500707856013300722 2007 eng d00aLocal Monitor Implementation for Decentralized Intrusion Detection in Secure Multi-Agent Systems0 aLocal Monitor Implementation for Decentralized Intrusion Detecti a454–4593 a

This paper focuses on the detection of misbehaving agents within a group of mobile robots. A novel approach to automatically synthesize a decentralized Intrusion Detection System (IDS) as well as an efficient implementation of local monitors are presented. In our scenario, agents perform possibly different independent tasks, but cooperate to guarantee the entire system

10aEmbedded Control10aRobotics1 aFagiolini, A1 aValenti, G1 aPallottino, L.1 aDini, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/local-monitor-implementation-decentralized-intrusion-detection-secure-multi-agent01750nas a2200157 4500008004100000245011500041210006900156300001200225520113700237653002101374653001301395100001901408700001501427700001601442856013401458 2007 eng d00aProbabilistic verification of decentralized multi-agent control strategies: a case study in conflict avoidance0 aProbabilistic verification of decentralized multiagent control s a170-1753 a

Many challenging verification problems arise from complex hybrid automata that model decentralized control systems. As an example, we will consider decentralized policies that steer multiple vehicles in a shared environment: properties of safety and liveness, such as collision avoidance and ultimate convergence of all vehicles to their goals, must be verified. To formally verify the behavior of proposed policies, it is desired to identify the broadest class of start and goal configurations, such that safety and liveness would be guaranteed. Simple conditions are proposed to identify such a class: ideally, a formal proof that such conditions are necessary and sufficient for safety and liveness is requested. Unfortunately, in decentralized control frameworks classical approaches are difficult to apply. Hence, probabilistic verification method can be applied to quantify the accuracy and the confidence of the veridicity of the desired predicate. The probabilistic verification method is applied to a recently proposed cooperative and completely decentralized collision avoidance policy for non-holonomic vehicles.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aBicchi, A.1 aFrazzoli, E uhttp://www.centropiaggio.unipi.it/publications/probabilistic-verification-decentralized-multi-agent-control-strategies-case-study01483nas a2200157 4500008004100000245007500041210006700116300001400183490000700197520094100204653002101145653001301166100001501179700001501194856011601209 2007 eng d00aOn the Stabilization of Linear Systems Under Assigned I/O Quantization0 aStabilization of Linear Systems Under Assigned IO Quantization a1994-20000 v523 a

This paper is concerned with the stabilization of discrete-time linear systems with quantization of the input and output spaces, i.e., when available values of inputs and outputs are discrete. Unlike most of the existing literature, we assume that how the input and output spaces are quantized is a datum of the problem, rather than a degree of freedom in design. Our focus is hence on the existence and synthesis of symbolic feedback controllers, mapping output words into the input alphabet, to steer a quantized I/O system to within small invariant neighborhoods of the equilibrium starting from large attraction basins. We provide a detailed analysis of the practical stabilizability of systems in terms of the size of hypercubes bounding the initial conditions, the state transient and the steady state evolution. We also provide an explicit construction of a practically stabilizing controller for the quantized I/O case.

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/stabilization-linear-systems-under-assigned-io-quantization.html01537nas a2200169 4500008004100000245007300041210006900114300001400183520095600197653002101153653001301174100001301187700001701200700001501217700001501232856012001247 2007 eng d00aSteering Dynamical Systems with Finite Plans and Limited Path Length0 aSteering Dynamical Systems with Finite Plans and Limited Path Le a4686-46903 a

Complex dynamical systems can be steered by using symbolic input plans. These plans must have a finite descriptive length, and can be expressed by means of words chosen in an alphabet of symbols. In this way, such plans can be sent through a limited capacity channel to a remote system, where they are decoded in suitable control actions. The choice of this symbols is essential to efficiently encode steering plans. To this aim, in this paper, we state the problem of finding symbols maximizing the interval of points reachable by the system along paths with constrained length. We focus on the problem with two symbols, and compare the results with those produced by plans not accounting for the length constraint. Moreover, the behavior of a simple helicopter, steered by both kinds of plans, has been simulated, in order to illustrate the power of the overall control system, and to emphasize the improvements introduced by the new plans.

10aEmbedded Control10aRobotics1 aGreco, L1 aFagiolini, A1 aBicchi, A.1 aPiccoli, B uhttp://www.centropiaggio.unipi.it/publications/steering-dynamical-systems-finite-plans-and-limited-path-length.html01046nas a2200205 4500008004100000245010700041210006900148300001000217490000700227520034300234653002100577653001300598100001300611700001500624700001700639700001600656700001500672700001600687856013700703 2007 eng d00aSymbolic Planning and Control of Robot Motion: Finding the Missing Pieces of Current Methods and Ideas0 aSymbolic Planning and Control of Robot Motion Finding the Missin a61-700 v143 a

Approaches to robot motion planning and control that involve tools such as automata, languages, temporal logics, and grammars, have been recently termed "symbolic." In this article, we review some existing results, discuss their relevance and applicability, and outline some of the main open questions and challenges in the area.

10aEmbedded Control10aRobotics1 aBelta, C1 aBicchi, A.1 aEgerstedt, M1 aFrazzoli, E1 aKlavins, E1 aPappas, G J uhttp://www.centropiaggio.unipi.it/publications/symbolic-planning-and-control-robot-motion-finding-missing-pieces-current-methods-and00990nas a2200145 4500008004100000245013700041210006900178260001000247520039500257653001300652100001700665700001100682700001500693856013600708 2007 eng d00aVariable Impedance Actuations for Physical Human Cooperating Robots: a Comparative Analysis of Performance, Safety and Dependability0 aVariable Impedance Actuations for Physical Human Cooperating Rob cApril3 a

An antagonistic actuation with variable stiffness is proposed for ensuring safety and performance in human friendly robotic applications. Various arrangements are analysed with respect to performance, safety and dependability. The results are expected to provide useful guidelines for choosing an actuation mechanism and its implementation for human-robot interactive applications.

10aRobotics1 aFilippini, R1 aSen, S1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/variable-impedance-actuations-physical-human-cooperating-robots-comparative-analysis01428nas a2200181 4500008004100000245008500041210006900126260003000195520078400225653002101009653001301030100001801043700001501061700001301076700001301089700001501102856012901117 2006 eng d00aAdaptive non Linear Control of Dynamic Mobile Robots with Parameters Uncertainty0 aAdaptive non Linear Control of Dynamic Mobile Robots with Parame aBologna, ItalycSeptember3 a

Research of a modular stabilizing control law for uncertain, nonholonomic mobile systems with actuators limitation has been investigated. Modular design allows the definition of a stabilizing control law for the kinematic model. The presence of uncertainties in the actuators parameters or in the vehicle dynamics has been treated both adding suitable components to the Lyapunov function and using parameters adaptation laws (e.g. adaptive control and backstepping techniques). Simulations are reported for the set point stabilization of a unicycle like vehicle showing the feasibility of the proposed approach. Torque limitations for a unicycle like vehicle has been investigated using backstepping techniques for the vehicle tracking problem. Simulations are reported.

10aEmbedded Control10aRobotics1 aFontanelli, D1 aViviani, R1 aGreco, L1 aCaiti, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-non-linear-control-dynamic-mobile-robots-parameters-uncertainty.html00534nas a2200133 4500008004100000245008700041210006900128300001000197653001300207100001700220700001500237700001500252856013300267 2006 eng d00aCasting Robotic end-effectors to reach far objects in space and planetary missions0 aCasting Robotic endeffectors to reach far objects in space and p a28-3010aRobotics1 aFagiolini, A1 aTorelli, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/casting-robotic-end-effectors-reach-far-objects-space-and-planetary-missions.html00442nas a2200133 4500008004100000245002600041210002500067250003300092260005700125653002100182653001300203100001500216856007700231 2006 eng d00aControllo, Teoria del0 aControllo Teoria del aXXI Secolo – Aggiornamento bIstituto della Enciclopedia Italiana ``G. Treccani''10aEmbedded Control10aRobotics1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllo-teoria-del.html01455nas a2200157 4500008004100000245008500041210006900126520086800195653002101063653001301084100001901097700001701116700001601133700001501149856013301164 2006 eng d00aDecentralized and scalable conflict resolution strategy for multi-agents systems0 aDecentralized and scalable conflict resolution strategy for mult3 a

A decentralized cooperative collision avoidance control policy for planar vehicle recently proposed is herein considered. Given some simple conditions on initial configurations of agents, the policy is known to ensure safety (i.e., collision avoidance) for an arbitrarily large number of vehicles. The method is highly scalable, and effective solutions can be obtained for several tens of autonomous agents. On the other hand, the liveness property of the policy, i.e. the capability of negotiating a solution in finite time, is not yet completely understood. First a 3D workspace extension is proposed. Furthermore, based on a condition on target configuration previously proposed, some general results on the liveness property are reported. Finally, qualitative evaluations on the strategy and on the proposed target sparsity condition are pointed out.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aScordio, V G1 aFrazzoli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-and-scalable-conflict-resolution-strategy-multi-agents-systems.html01565nas a2200193 4500008004100000245006900041210006200110260000900172300001200181520095300193653002101146653001301167100001701180700001501197700001401212700001901226700001501245856011101260 2006 eng d00aOn the Design and Control of Wireless Networked Embedded Systems0 aDesign and Control of Wireless Networked Embedded Systems bIEEE a440-4453 a

Wireless networked embedded systems are becoming increasingly important in a wide area of technical fields. In this tutorial paper we present recent results on design and control of these systems developed within the project Reconfigurable Ubiquitous Networked Embedded Systems (RUNES), which is an European Integrated Project with the aim to control complexity in networked embedded systems by developing robust and scalable middleware systems. New components for control under varying network conditions are discussed for the RUNES architecture. The complexity of the closed-loop system is increased due to the coupling with the disturbances introduced by the communication system. The network may introduce additional delays, jitter, data rate limitations, packet losses etc. Experimental work on integration test beds that demonstrates these results is shown together with motivating links to the RUNES disaster relief tunnel scenario.

10aEmbedded Control10aRobotics1 aArzén, K -E1 aBicchi, A.1 aHailes, S1 aJohansson, K H1 aLygeros, J uhttp://www.centropiaggio.unipi.it/publications/design-and-control-wireless-networked-embedded-systems.html01455nas a2200169 4500008004100000245007400041210006900115300000900184490000700193520088800200653002101088653001301109100001501122700001401137700001501151856011901166 2006 eng d00aFeedback Encoding for Efficient Symbolic Control of Dynamical Systems0 aFeedback Encoding for Efficient Symbolic Control of Dynamical Sy a1-160 v513 a

The problem of efficiently steering dynamical systems by generating finite input plans is considered. Finite plans are finite–length words constructed on a finite alphabet of input symbols, which could be e.g. transmitted through a limited capacity channel to a remote system, where they can be decoded in suitable control actions. Efficiency is considered in terms of the computational complexity of plans, and in terms of their description length (in number of bits). We show that, by suitable choice of the control encoding, finite plans can be efficiently built for a wide class of dynamical systems, computing arbitrarily close approximations of a desired equilibrium in polynomial time. The paper also investigates how the efficiency of planning is affected by the choice of inputs, and provides some results as to optimal performance in terms of accuracy and range.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aMarigo, A1 aPiccoli, B uhttp://www.centropiaggio.unipi.it/publications/feedback-encoding-efficient-symbolic-control-dynamical-systems.html01946nas a2200229 4500008004100000245006900041210006900110260002000179300001000199490001600209520122400225653002101449653001301470100001601483700001501499700001301514700003201527700001301559700001601572700001401588856011401602 2006 eng d00aHybrid Modelling and Control of the Common Rail Injection System0 aHybrid Modelling and Control of the Common Rail Injection System bSpringer-Verlag a79-920 v3927 / 20063 a

We present an industrial case study in automotive control of significant complexity: the new common rail fuel injection system for Diesel engines, currently under production by Magneti Marelli Powertrain. In this system, a flow-rate valve, introduced before the High Pressure (HP) pump, regulates the fuel flow that supplies the common rail according to the engine operating point. The standard approach followed in automotive control is to use a mean-value model for the plant and to develop a controller based on this model. In this particular case, this approach does not provide a satisfactory solution as the discrete-continuous interactions in the fuel injection system, due to the slow time-varying frequency of the HP pump cycles and the fast sampling frequency of sensing and actuation, play a fundamental role. We present a design approach based on a hybrid model of the Magneti Marelli Powertrain common-rail fuel-injection system for four-cylinder multi-jet engines and a hybrid approach to the design of a rail pressure controller. The hybrid controller is compared with a classical mean-value based approach to automotive control design whereby the quality of the hybrid solution is demonstrated.

10aEmbedded Control10aRobotics1 aBalluchi, A1 aBicchi, A.1 aMazzi, E1 aVincentelli, Sangiovanni, A1 aSerra, G1 aHespanha, J1 aTiwari, A uhttp://www.centropiaggio.unipi.it/publications/hybrid-modelling-and-control-common-rail-injection-system.html01362nas a2200205 4500008004100000245007300041210006900114260002000183300001200203490001600215520070100231653002100932653001300953100001500966700001400981700001500995700001601010700001401026856011601040 2006 eng d00aImproving efficiency of finite plans by optimal choice of input sets0 aImproving efficiency of finite plans by optimal choice of input  bSpringer-Verlag a108-1220 v3927 / 20063 a

Finite plans proved to be an efficient method to steer complex control systems via feedback quantization. Such finite plans can be encoded by finite–length words constructed on suitable alphabets, thus permitting transmission on limited capacity channels. In particular flat systems can be steered computing arbitrarily close approximations of a desired equilibrium in polynomial time. The paper investigates how the efficiency of planning is affected by the choice of inputs, and provides some results as to optimal performance in terms of accuracy and range. Efficiency is here measured in terms of computational complexity and description length (in number of bits) of finite plans.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aMarigo, A1 aPiccoli, B1 aHespanha, J1 aTiwari, A uhttp://www.centropiaggio.unipi.it/publications/improving-efficiency-finite-plans-optimal-choice-input-sets.html01493nas a2200193 4500008004100000245006500041210006400106260003300170300001400203490000700217520082500224653004401049653001301093100001601106700001501122700001501137700003501152856011201187 2006 eng d00aOptimal Mechanical/Control Design for Safe and Fast Robotics0 aOptimal MechanicalControl Design for Safe and Fast Robotics bSpringer Berlin / Heidelberg a311 - 3200 v213 a

The problem to ensure safety of performant robot arms during task execution was previously investigated by authors. The problem can be approached by studying an optimal control policy, the "Safe Brachistocrone", whose solutions are joint impedance trajectories coordinated with desired joint velocities. Transmission stiffness is chosen so as to achieve minimum-time task execution for the robot, while guaranteeing an intrinsic safety level in case of an unexpected collision between a link of the arm and a human operator. In this paper we extend this approach to more general classes of robot actuation systems, whereby other impedance parameters beside stiffness (such as e.g. joint damping and/or plasticity) can vary. We report on a rather extensive experimental campaign validating the proposed approach.

10aPhysical Human-Robot Interaction (pHRI)10aRobotics1 aTonietti, G1 aSchiavi, R1 aBicchi, A.1 aMarcelo H. Ang, Oussama Khatib uhttp://www.centropiaggio.unipi.it/publications/optimal-mechanicalcontrol-design-safe-and-fast-robotics.html01824nas a2200217 4500008004100000245007700041210006900118260003300187300001400220490000700234520109300241653004401334653001301378100001701391700001501408700001101423700001601434700001501450700001901465856012201484 2006 eng d00aOptimization and Fail-Safety Analysis of Antagonistic Actuation for pHRI0 aOptimization and FailSafety Analysis of Antagonistic Actuation f bSpringer Berlin / Heidelberg a109 - 1180 v223 a

In this paper we consider some questions in the design of actuators for physical Human-Robot Interaction (pHRI) under strict safety requirements in all circumstances, including unexpected impacts and HW/SW failures. We present the design and optimization of agonistic-antagonistic actuation systems realizing the concept of variable impedance actuation (VIA). With respect to previous results in the literature, in this paper we consider a realistic physical model of antagonistic systems, and include the analysis of the effects of cross-coupling between actuators. We show that antagonistic systems compare well with other possible approaches in terms of the achievable performance while guaranteeing limited risks of impacts. Antagonistic actuation systems however are more complex in both hardware and software than other schemes. Issues are therefore raised, as to fault tolerance and fail safety of different actuation schemes. In this paper, we analyze these issues and show that the antagonistic implementation of the VIA concept fares very well under these regards also.

10aPhysical Human-Robot Interaction (pHRI)10aRobotics1 aBoccadamo, G1 aSchiavi, R1 aSen, S1 aTonietti, G1 aBicchi, A.1 aChristensen, H uhttp://www.centropiaggio.unipi.it/publications/optimization-and-fail-safety-analysis-antagonistic-actuation-phri.html01394nas a2200157 4500008004100000245009300041210006900134260000900203300001200212520081100224653002101035653001301056100001501069700001501084856013701099 2006 eng d00aPractical stabilization of LTI SISO systems under assigned Input and Output quantization0 aPractical stabilization of LTI SISO systems under assigned Input cJuly a353-3583 a

This work is concerned with the practical stabilization of discrete–time SISO linear systems under assigned quantization of the input and output spaces. A controller is designed which guarantees effective practical stability properties. Unlike most of the existing literature, quantization is supposed to be a problem datum rather than a degree of freedom in design. Moreover, in the framework of control under assigned quantization, results are concerned with state quantization only and do not include the quantized output feedback case considered here. While standard stability analysis techniques are based on Lyapunov theory and invariant ellipsoids, our study of the closed loop dynamics involves a particularly suitable family of sets, which are hypercubes in controller form coordinates.

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/practical-stabilization-lti-siso-systems-under-assigned-input-and-output-quantization01650nas a2200169 4500008004100000245010400041210006900145300001400214520101200228653002101240653001301261100001901274700001701293700001601310700001501326856013901341 2006 eng d00aProbabilistic verification of a decentralized policy for conflict resolution in multi-agent systems0 aProbabilistic verification of a decentralized policy for conflic a2448-24533 a

In this paper, we consider a decentralized cooperative control policy proposed recently for steering multiple non-holonomic vehicles between assigned start and goal configurations while avoiding collisions. The policy is known to ensure safety (i.e., collision avoidance) for an arbitrarily large number of vehicles, if initial configurations satisfy certain conditions. The method is highly scalable, and effective solutions can be obtained for several tens of autonomous agents. On the other hand, the liveness property of the policy, i.e. the capability of negotiating a solution in finite time, is not yet completely understood. In this paper, we introduce a condition on the final vehicle configurations, which we conjecture to be sufficient for guaranteeing liveness. Because of the overwhelming complexity of proving the sufficiency of such condition, we assess the correctness of the conjecture in probability through the analysis of the results of a large number of randomized experiments.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aScordio, V G1 aFrazzoli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/probabilistic-verification-decentralized-policy-conflict-resolution-multi-agent-systems01029nas a2200337 4500008004100000245011100041210006900152260000900221653001300230100001300243700002200256700001500278700001600293700001500309700001600324700001700340700001400357700001600371700001700387700001500404700001700419700001500436700001400451700001100465700001700476700001600493700001500509700001500524700001600539856013600555 2006 eng d00aSafe and Dependable Physical Human-Robot Interaction in Anthropic Domains: State of the Art and Challenges0 aSafe and Dependable Physical HumanRobot Interaction in Anthropic bIEEE10aRobotics1 aAlami, R1 aAlbu-Schaeffer, A1 aBicchi, A.1 aBischoff, R1 aChatila, R1 aDe Luca, A.1 aDe Santis, A1 aGiralt, G1 aGuiochet, J1 aHirzinger, G1 aIngrand, F1 aLippiello, V1 aMattone, R1 aPowell, D1 aSen, S1 aSiciliano, B1 aTonietti, G1 aVillani, L1 aBicchi, A.1 aDe Luca, A. uhttp://www.centropiaggio.unipi.it/publications/safe-and-dependable-physical-human-robot-interaction-anthropic-domains-state-art-and01910nas a2200193 4500008004100000245010600041210006900147520122400216653002101440653001301461100001401474700001701488700001401505700001901519700001501538700001201553700001501565856013601580 2006 eng d00aA scalable platform for safe and secure decentralized traffic management of multiagent mobile systems0 ascalable platform for safe and secure decentralized traffic mana3 a

In this paper we describe the application of wireless sensor networking techniques to address the realization of a safe and secure decentralized traffic management system. We consider systems of many heterogeneous autonomous vehicles moving in a shared environment. Each vehicle is assumed to have different and possibly unspecified tasks, but they cooperate to avoid collisions. We are interested in designing a scalable architecture capable of accommodating a very large and dynamically changing number of vehicles, guaranteeing their safety (i.e., collision avoidance), the achievement of their goals, and security against potential adversaries. By properly distributing and revoking cryptographic keys we are able to protect communications from an external adversary as well as to detect non-cooperative, possibly malicious vehicles and trigger suitable countermeasures. In our architecture, scalability is obtained by decentralization, i.e. each vehicle is regarded as an autonomous agent capable of processing information concerning its own state and the state of only a fixed, small number of ``neighboring'' agents. Ad-hoc wireless sensor networks are employed to provide support for this architecture.

10aEmbedded Control10aRobotics1 aDanesi, A1 aFagiolini, A1 aSavino, I1 aPallottino, L.1 aSchiavi, R1 aDini, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/scalable-platform-safe-and-secure-decentralized-traffic-management-multiagent-mobile00759nas a2200169 4500008004100000245008900041210006900130520015200199653002100351653001300372100001400385700001600399700001500415700001500430700001200445856013200457 2006 eng d00aSecurity and Advanced Control Issues in a Robotic Platform for Monitoring and Relief0 aSecurity and Advanced Control Issues in a Robotic Platform for M3 a

This paper provides an architectural overview and a first implementation of an heterogeneous agent network composed by mobile robots of di

10aEmbedded Control10aRobotics1 aDanesi, A1 aSavino, I M1 aSchiavi, R1 aBicchi, A.1 aDini, G uhttp://www.centropiaggio.unipi.it/publications/security-and-advanced-control-issues-robotic-platform-monitoring-and-relief.html01436nas a2200181 4500008004100000245006700041210006700108300001400175520084200189653002101031653001301052100001701065700001301082700001501095700001501110700001401125856011501139 2006 eng d00aSymbolic Control for Underactuated Differentially Flat Systems0 aSymbolic Control for Underactuated Differentially Flat Systems a1649-16543 a

In this paper we address the problem of generating input plans to steer complex dynamical systems in an obstacle-free environment. Plans considered admit a finite description length and are constructed by words on an alphabet of input symbols, which could be e.g. transmitted through a limited capacity channel to a remote system, where they can be decoded in suitable control actions. We show that, by suitable choice of the control encoding, finite plans can be efficiently built for a wide class of dynamical systems, computing arbitrarily close approximations of a desired equilibrium in polynomial time. Moreover, we illustrate by simulations the power of the proposed method, solving the steering problem for two examples in the class of underactuated systems, which have attracted wide attention in the recent literature.

10aEmbedded Control10aRobotics1 aFagiolini, A1 aGreco, L1 aBicchi, A.1 aPiccoli, B1 aMarigo, A uhttp://www.centropiaggio.unipi.it/publications/symbolic-control-underactuated-differentially-flat-systems.html01504nas a2200181 4500008004100000245008400041210006900125260007900194520081300273653002101086653001301107100001501120700001301135700001801148700001301166700001501179856012801194 2005 eng d00aAdaptive nonlinear control of dynamic mobile robots with parameters uncertainty0 aAdaptive nonlinear control of dynamic mobile robots with paramet bDipartimento di Sistemi Elettrici e Automazione, Università di Pisa3 a

Research of a modular stabilizing control law for uncertain, nonholonomic mobile systems with actuators limitation has been investigated. Modular design allows the definition of a stabilizing control law for the kinematic model. The presence of uncertainties in the actuators parameters or in the vehicle dynamics has been treated both adding suitable components to the Lyapunov function and using parameters adaptation laws (e.g. adaptive control and backstepping techniques). Simulations are reported for the set point stabilization of a unicycle like vehicle showing the feasibility of the proposed approach. Torque limitations for a unicycle like vehicle has been investigated using backstepping techniques for the vehicle tracking problem. Simulations are reported.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aCaiti, A1 aFontanelli, D1 aGreco, L1 aViviani, R uhttp://www.centropiaggio.unipi.it/publications/adaptive-nonlinear-control-dynamic-mobile-robots-parameters-uncertainty.html01558nas a2200157 4500008004100000245007800041210006900119300001400188490000700202520100400209653002101213653001301234100001501247700001501262856012301277 2005 eng d00aControl synthesis for practical stabilization of quantized linear systems0 aControl synthesis for practical stabilization of quantized linea a397–4100 v633 a

In this work we face the stability problem for quantized control systems (QCS). A discrete–time single–input linear model is considered and, motivated by technological applications, we assume that a uniform quantization of the control set is a priori fixed. As it is well known, for QCS only practical stability properties can be achieved, therefore we focus on the existence and construction of quantized controllers capable of steering a system to within invariant neighborhoods of the equilibrium. The main contribution of the paper consists in a theorem which provides a condition for the practical stabilization in a fixed number of steps: not only the result is interesting in itself, but also it enables to construct a family of stabilizing controllers by means of Model Predictive Control (MPC) techniques. In the last part of the paper some results on the characterization of controlled–invariant sets are reviewed and a lower bound on the size of invariant sets is provided.

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/control-synthesis-practical-stabilization-quantized-linear-systems.html01297nas a2200157 4500008004100000245008500041210006900126520071000195653002100905653001300926100001900939700001700958700001600975700001500991856013301006 2005 eng d00aDecentralized Cooperative Conflict Resolution for Multiple Nonholonomic Vehicles0 aDecentralized Cooperative Conflict Resolution for Multiple Nonho3 a

In this paper, we consider the problem of collision-free motion planning for multiple nonholonomic planar vehicles. Each vehicle is capable of moving at constant speed along paths with bounded curvature, and is aware of the position and heading of other vehicles within a certain sensing radius. No other information exchange is required between vehicles. We propose a spatially decentralized, cooperative hybrid control policy that ensures safety for arbitrary numbers of vehicles. Furthermore, we show that under certain conditions, the policy avoids dead- and livelock, and eventually all vehicles reach their intended targets. Simulations and experimental results are presented and discussed.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aScordio, V G1 aFrazzoli, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-cooperative-conflict-resolution-multiple-nonholonomic-vehicles.html01504nas a2200145 4500008004100000245010700041210006900148300001200217520093800229653001301167100001601180700001501196700001501211856013201226 2005 eng d00aDesign and Control of a Variable Stiffness Actuator for Safe and Fast Physical Human/Robot Interaction0 aDesign and Control of a Variable Stiffness Actuator for Safe and a528-5333 a

This paper is concerned with the design and control of actuators for machines and robots physically interacting with humans. According to criteria established in our previous work on mechanical-control co-design for intrinsically safe, yet performant machines, we pursue the Variable Impedance Actuation (VIA) approach, purporting actuators that can control in real-time both the reference position and the mechanical impedance of the moving parts in the machine. In this paper we describe an implementation of such concepts, consisting of a novel electromechanical Variable Stiffness Actuation (VSA) motor. The design and the functioning principle of the VSA are reported, along with the analysis of its dynamic behavior. A novel scheme for feedback control of this device is presented, along with experimental results showing performance and safety of a one-link arm actuated by the VSA motor.

10aRobotics1 aTonietti, G1 aSchiavi, R1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/design-and-control-variable-stiffness-actuator-safe-and-fast-physical-humanrobot00461nas a2200145 4500008004100000245004300041210004300084260002100127300001200148653001200160653001300172100001500185700002000200856009500220 2005 eng d00aFlusso tattile ed illusione sensoriale0 aFlusso tattile ed illusione sensoriale aRoma, ItalycMay a245-24910aHaptics10aRobotics1 aBicchi, A.1 aScilingo, E. P. uhttp://www.centropiaggio.unipi.it/publications/flusso-tattile-ed-illusione-sensoriale.html01218nas a2200193 4500008004100000245008900041210006900130520056300199653001300762100001800775700001500793700001300808700001600821700001600837700001600853700001900869700001600888856012000904 2005 eng d00aFrom tele-laboratory to e-learning in automation curricula at the university of Pisa0 aFrom telelaboratory to elearning in automation curricula at the 3 a

The design and development of computational infrastructures supporting existing tele-laboratory experiences in the field of automation and robotics are described. The goal of the activity is to provide a proper e-learning environment in which remote laboratory experiences are integrated in a coherent way. The addition of e-learning features, as self-assessment and progress monitoring tools, asynchronous tutor interaction, authentication, evaluation and follow-up features, has led also to the modification of the original tele-laboratory set-up.

10aRobotics1 aBalestrino, A1 aBicchi, A.1 aCaiti, A1 aCalabrò, V1 aCecchini, T1 aCoppelli, A1 aPallottino, L.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/tele-laboratory-e-learning-automation-curricula-university-pisa.html00586nas a2200157 4500008004100000245007900041210006900120260001900189653002100208653001300229100001500242700001300257700001700270700001600287856012500303 2005 eng d00aHybrid Modelling of an Electronically Controlled Limited Slip Differential0 aHybrid Modelling of an Electronically Controlled Limited Slip Di c8-10 September10aEmbedded Control10aRobotics1 aBicchi, A.1 aGreco, G1 aGuiggiani, M1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/hybrid-modelling-electronically-controlled-limited-slip-differential.html01737nas a2200193 4500008004100000245009500041210006900136260001800205300001600223490000700239520104900246653002101295653001301316100001601329700001501345700001501360700003301375856013501408 2005 eng d00aMaximizing the stability radius of a set of systems under real-time scheduling constraints0 aMaximizing the stability radius of a set of systems under realti cNovember 2005 a1790–17950 v503 a

We address the problem of synthesising real-time embedded controllers taking into account constraints deriving from the implementation platform. Assuming a time-triggered model of computation for tasks controlling a set of independent systems and a real-time preemptive scheduling policy managing a single CPU processor board, we deal with two problems: 1- deciding whether a performance specification can be met on a given platform, 2- optimising performance on a platform. Decision variables of the design problems are the activation periods of the tasks , while the considered performance metric is the minimum stability radius attained over the different feedback loops, which is related to the technological feasibility of the controller and to the robustness of the controlled systems. The analytical formulation of the design problems enables efficient numerical solutions. The resulting control policies are directly implementable without performance degradation that may otherwise arise due to scheduling and execution delays.

10aEmbedded Control10aRobotics1 aPalopoli, L1 aPinello, C1 aBicchi, A.1 aSangiovanni-Vincentelli, A L uhttp://www.centropiaggio.unipi.it/publications/maximizing-stability-radius-set-systems-under-real-time-scheduling-constraints.html01003nas a2200169 4500008004100000245007700041210006900118300001200187490000700199520043900206653001300645100001500658700001300673700001900686700001600705856011200721 2005 eng d00aOn-line Robotic Experiments for Tele-Education at the University of Pisa0 aOnline Robotic Experiments for TeleEducation at the University o a217-2300 v223 a

In this paper we describe work being done at our department to make the Robotics Laboratory accessible to student and colleagues, to execute and watch real-time experiments at any time and from anywhere. We describe few different installations, and highlight the underlying philosophy, wich is aimed at enlarging the lab in all the dimensions of space, time, and available resources, through the use of Internet technologies.

10aRobotics1 aBicchi, A.1 aCaiti, A1 aPallottino, L.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/line-robotic-experiments-tele-education-university-pisa.html02054nas a2200181 4500008004100000245007900041210006900120260001200189300001400201490000700215520144800222653002101670653001301691100001601704700001501720700001601735856012101751 2005 eng d00aPath-Following with a Bounded-Curvature Vehicle: a Hybrid Control Approach0 aPathFollowing with a BoundedCurvature Vehicle a Hybrid Control A cOctober a1228-12470 v783 a

In this paper, we consider the problem of stabilizing the kinematic model of a car to a path in the plane under rather general conditions. The path is subject to very mild restrictions, while the car model, although rather simplified, contains the most relevant limitations inherent in wheeled robots kinematics. Namely, the car can only move forward, its steering radius is lower bounded and a limited sensory information only provides a partial knowledge of some state parameters. In particular, we consider the case that the current distance and the heading angle error with respect to the closest point on the reference path can be measured but only the sign of the path curvature is detected. These constraints are such to make classical control techniques inefficient. As the feedback information is both continuous and discrete, the hybrid systems formalism turns out to be well appropriate to model the problem. The proposed approach is based on optimal control techniques successfully applied in a previous work for following rectilinear path. We propose here an extension to the tracking of more general paths with moderate curvature. The stability of the closed-loop system is proved by means of the hybrid system formalism and hybrid formal verification techniques. Finally, the practicality of the proposed approach, in spite of non–idealities in real-world applications, is discussed by reporting experimental results.

10aEmbedded Control10aRobotics1 aBalluchi, A1 aBicchi, A.1 aSouères, P uhttp://www.centropiaggio.unipi.it/publications/path-following-bounded-curvature-vehicle-hybrid-control-approach.html01617nas a2200265 4500008004100000245008400041210006900125520078400194653001300978100002200991700001501013700001701028700001501045700001601060700001701076700001401093700001701107700001701124700001501141700001501156700001701171700001601188700001501204856013201219 2005 eng d00aPhysical Human-Robot Interaction in Anthropic Domains: Safety and Dependability0 aPhysical HumanRobot Interaction in Anthropic Domains Safety and 3 a

In this paper we describe the motivations and the aim ofthe EURON-2 research project ``\underline{P}hysical \underline{H}uman-\underline{R}obot \underline{I}nteraction in Anthropic \underline{Dom}ains'' (PRHIDOM). This project, which moves along the lines indicated by the 1$^{st}$ IARP/IEEE-RAS Workshop on Technical Challenge for Dependable Robots in Human Environments \cite{iarp01}, is about ``charting'' the new ``territory'' of physical Human-Robot Interaction (pHRI). To ensure these goals, the integration competences in control, robotics, design and realization of mechanical systems, human-machine interaction, and in safety-dependability of mechatronic systems is required. The PHRIDOM Consortium is composed of 5 partners from 3 different European countries.

10aRobotics1 aAlbu-Schaeffer, A1 aBicchi, A.1 aBoccadamo, G1 aChatila, R1 aDe Luca, A.1 aDe Santis, A1 aGiralt, G1 aHirzinger, G1 aLippiello, V1 aMattone, R1 aSchiavi, R1 aSiciliano, B1 aTonietti, G1 aVillani, L uhttp://www.centropiaggio.unipi.it/publications/physical-human-robot-interaction-anthropic-domains-safety-and-dependability.html01449nas a2200193 4500008004100000245005400041210005400095300001600149520083600165653002101001653001301022100001601035700001601051700001501067700001501082700003101097700001901128856010801147 2005 eng d00aRandomized Algorithms for Platform–based Design0 aRandomized Algorithms for Platform–based Design a6638 - 66433 a

The design of automotive control systems is becoming increasingly complex as the level of performance required by car manufactures grows continuously and the constraints on cost and development time imposed by the market become tighter. A successful design, without costly and time consuming re-design cycles, can be achieved only by using an efficient design methodology that allows for component re-use and evaluation of platform requirements at the early stages of the design flow. In this paper, we illustrate a control-implementation design methodology for the development of embedded controllers by composition of algorithms picked up from libraries. Randomized algorithms and hybrid system theory are used to develop techniques for functional and architecture evaluations, which are implemented in a prototype tool.

10aEmbedded Control10aRobotics1 aAgostini, A1 aBalluchi, A1 aBicchi, A.1 aPiccoli, B1 aSangiovanni Vincentelli, A1 aZadarnowska, K uhttp://www.centropiaggio.unipi.it/publications/randomized-algorithms-platform%E2%80%93based-design.html01616nas a2200145 4500008004100000245005800041210005700099300001400156520113300170653001301303100001701316700001501333700001501348856010701363 2005 eng d00aVisual-based Feedback Control of Casting Manipulation0 aVisualbased Feedback Control of Casting Manipulation a2203-22083 a

In this paper, we present a method to control casting manipulation by means of real-time visual feedback. Casting manipulation is a technique to deploy a robotic end-effector at large distances from the robot's base, by throwing the end-effector and controlling its ballistic flight using forces transmitted through a light tether connected to the end-effector itself. The tether cable can also be used to retrieve the end-effector and exert forces on the robot's environment. Previous work has shown that casting manipulation is able to catch objects at a large distance, proving it viable for applications such as sample acquisition and return, rescue, etc. In previous experiments, the position of the target object was known exactly. In this paper, we present a first attempt at closing a real-time control loop on casting manipulation using visual feedback of moving targets. As accurate planning methods developed for off-line open-loop planning cannot be used in real-time, we develop a simplified model and control algorithm, whose effectiveness is demonstrated through experiments.

10aRobotics1 aFagiolini, A1 aArisumi, H1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/visual-based-feedback-control-casting-manipulation.html01667nas a2200169 4500008004100000245009300041210006900134300001400203520104000217653002101257653001301278100001501291700001601306700001501322700001901337856014101356 2004 eng d00aControl of Distributed Embedded Systems in the Presence of Unknown–but–Bounded Noise0 aControl of Distributed Embedded Systems in the Presence of Unkno a1448-14533 a

In this paper we consider the problem of controlling multiple scalar systems through a limited capacity shared channel. Each system is affected by process noise and can be controlled byactuators with values in a {\em fixed}inite set. The control objective is to bound the evolution of the systems in specified sets (controlled invariance). Our goal is to find an optimal allocation of the shared communication resource to the different control activities and to identify correct choices for the design parameters. The paper provides fundamental conceptual tools to attack the design problem in the formal framework of an optimization problem. Namely, we give a feasibility criterion to decide whether a set of design parameters conforms with a control specification (i.e., with the controlled invariance of a specified set for each system). Moreover, we offer the explicit computation of the minimum bit rate necessary for the controlled invariance of a set, which is of utmost importance for solving the optimization problem.

10aEmbedded Control10aRobotics1 aPicasso, B1 aPalopoli, L1 aBicchi, A.1 aJohansson, K H uhttp://www.centropiaggio.unipi.it/publications/control-distributed-embedded-systems-presence-unknown%E2%80%93%E2%80%93bounded-noise.html01283nas a2200157 4500008004100000245009000041210006900131300001400200520068900214653002100903653001300924100001900937700001700956700001500973856013700988 2004 eng d00aDecentralized Cooperative Conflict Resolution Among Multiple Autonomous Mobile Agents0 aDecentralized Cooperative Conflict Resolution Among Multiple Aut a4758-47633 a

In this paper we consider policies for cooperative, decentralized traffic management among a number of autonomous mobile agents. The conflict resolution problem is addressed considering realistic restrictions on possible maneuvers. We formulate this problem as one in Mixed Integer Linear Programming (MILP). The method, which proves successful in a centralized implementation with a large number of cooperating agents, is also extended to a decentralized setting. Conditions for the existence of conflict avoidance maneuvers for a system of 5 autonomous agents with a transitive information structure are provided, along with the explicit policy to be applied by each agent.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aScordio, V G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/decentralized-cooperative-conflict-resolution-among-multiple-autonomous-mobile-agents01260nas a2200205 4500008004100000245003600041210003600077260002000113300001200133490000900145520070800154653002100862653001300883100001500896700001400911700001500925700001200940700001400952856008800966 2004 eng d00aDiscrete and Hybrid Nonholonomy0 aDiscrete and Hybrid Nonholonomy bSpringer-Verlag a157-1720 v29933 a

In this paper we consider the generalization of the classical notion of nonholonomy of smooth constraints in analytical mechanics, to a substantially wider set of systems, allowing for discrete and hybrid (mixed continuous and discrete) configurations and transitions. We show that the general notion of nonholonomy can be captured by the definition of two different types of nonholonomicbehaviours, which we call {\em internal}nd {\em external}, respectively. Examples are reported of systems exhibiting either the former only, or the latter only, or both. For some classes of systems, we provide equivalent or sufficient characterizations of such definitions, which allow for practical tests.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aMarigo, A1 aPiccoli, B1 aAlur, R1 aPappas, G uhttp://www.centropiaggio.unipi.it/publications/discrete-and-hybrid-nonholonomy.html01523nas a2200145 4500008004100000245011000041210006900151300001200220490000700232520096200239653001301201100001501214700001601229856013201245 2004 eng d00aFast and Soft Arm Tactics: Dealing with the Safety-Performance Trade-Off in Robot Arms Design and Control0 aFast and Soft Arm Tactics Dealing with the SafetyPerformance Tra a22–330 v113 a

In this paper we discuss the problem of achieving good performance in accuracy and promptness by a robot manipulator under the condition that safety is guaranteed throughout task execution. The particular but basic problem of single-joint actuation is considered in detail. Intuitively, while a rigid and powerful structure of the arm would favour its performance, lightweight compliant structures are more suitable to safe operation. The quantitative analysis of the resulting design trade-off between safety and performance is one of the objectives of our work. Such analysis has a strong impact on how robot mechanisms and controllers should be designed for human-interactive applications. We discuss few different possible concepts for safely actuating joints, and focus our attention on one, the Variable-Stiffness Transmission (VST) approach. Some aspects related to the implementation of the mechanics and control of VST joints are reported.

10aRobotics1 aBicchi, A.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/fast-and-soft-arm-tactics-dealing-safety-performance-trade-robot-arms-design-and01480nas a2200181 4500008004100000245011500041210006900156260001400225300001200239490000700251520081800258653002101076653001301097100001601110700001801126700001501144856013901159 2004 eng d00aA Hybrid-Control Approach to the Parking Problem of a Wheeled Vehicle Using Limited View-Angle Visual Feedback0 aHybridControl Approach to the Parking Problem of a Wheeled Vehic cApril-May a437-4480 v233 a

In this paper we consider the mobile robot parking problem, i.e. the stabilization of a wheeled vehicle to a given position and orientation, using only visual feedback from low-cost cameras. The practically most relevant problem of keeping the tracked features in sight of the camera while maneuvering to park the vehicle is taken into account. This constraint, often neglected in the literature, combines with the nonholonomic nature of the vehicle kinematics in a challenging controller design problem. We provide an effective solution to such problem by using a combination of previous results on non-smooth control synthesis and recently developed hybrid control techniques. Simulations and experimental results on a laboratory vehicle are reported, showing the practicality of the proposed approach.

10aEmbedded Control10aRobotics1 aMurrieri, P1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/hybrid-control-approach-parking-problem-wheeled-vehicle-using-limited-view-angle-visual00524nas a2200133 4500008004100000022001800041245007900059210006900138260001000207653001300217100001500230700001600245856012900261 2004 eng d aPI2004A00007700aMeccanismo motoriduttore a rigidezza variabile e rapidamente controllabile0 aMeccanismo motoriduttore a rigidezza variabile e rapidamente con aItaly10aRobotics1 aBicchi, A.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/meccanismo-motoriduttore-rigidezza-variabile-e-rapidamente-controllabile.html01424nas a2200169 4500008004100000245004900041210004900090300001400139520089700153653002101050653001301071100001601084700001901100700001901119700001501138856010101153 2004 eng d00aMotion Planning through Symbols and Lattices0 aMotion Planning through Symbols and Lattices a3914-39193 a

In this paper we propose a new approach to motion planning, based on the introduction of a lattice structure in the workspace of the robot, leading to efficient computations of plans for rather complex vehicles, and allowing for the implementation of optimization procedures in a rather straightforward way. The basic idea is the purposeful restriction of the set of possible inputfunctions to the vehicle to a finite set of symbols, or {\em control quanta},which, under suitable conditions, generate a regular lattice of reachable points. Once the lattice is generated and a convenient description computed, standard techniques in integer linear programming can be used to find a plan very efficiently. We also provide a correct and complete algorithm to the problem of finding an optimized plan (with respect e.g. to length minimization) consisting in a sequence of graph searches.

10aEmbedded Control10aRobotics1 aPancanti, S1 aPallottino, L.1 aSalvadorini, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/motion-planning-through-symbols-and-lattices.html01556nas a2200229 4500008004100000245009900041210006900140260002000209300001200229520078400241653002101025653001301046100001501059700001601074700001601090700001701106700001701123700001601140700001801156700001601174856013601190 2004 eng d00aOn The Problem of Simultaneous Localization, Map Building, and Servoing of Autonomous Vehicles0 aProblem of Simultaneous Localization Map Building and Servoing o bSpringer Verlag a223-2393 a

In this chapter, we consider three of the main problems that arise in the navigation of autonomous vehicles in partially or totally unknown environments, i.e. building a map of the environment, self-localizing, and servoing the robot so as to achieve given goals based on sensorial information. As compared to most part of the existing literature on SLAM, we privilege here a system-theoretic view to the problem, which allows the localization and mapping problems to be cast in a unified framework with the control problem. The chapter is an overview of existing results in this vein, and of some interesting directions for research in the field. All chapters of this volume were revised and published online March 2005. The volume number was corrected from 4010 to 10.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aLorussi, F.1 aMurrieri, P1 aScordio, V G1 aSiciliano, B1 aDe Luca, A.1 aMelchiorri, C1 aCasalino, G uhttp://www.centropiaggio.unipi.it/publications/problem-simultaneous-localization-map-building-and-servoing-autonomous-vehicles.html01297nas a2200157 4500008004100000245005500041210005400096520078700150653002100937653001300958100001500971700001900986700001601005700001501021856010301036 2004 eng d00aQuantised Control in Distributed Embedded Systems.0 aQuantised Control in Distributed Embedded Systems3 a

Traditional control design is based on ideal assumptions concerning the amount, type and accuracy of the information flow that can be circulated across the controller. Unfortunately, real implementation platforms exhibit non-idealities that may substantially invalidate such assumptions. As a result, the system’s closed-loop performance can be severely affected and sometimes stability itself is jeopardised. These problems show up with particular strength when multiple feedback loops share a limited pool of computation and communication resources. In this case the designer is confronted with the challenging task of choosing at the same time the control law and the optimal allocation policy for the shared resources (control algortihm/system architecture co-design).

10aEmbedded Control10aRobotics1 aBicchi, A.1 aJohansson, K H1 aPalopoli, L1 aPicasso, B uhttp://www.centropiaggio.unipi.it/publications/quantised-control-distributed-embedded-systems.html02137nas a2200181 4500008004100000245008900041210006900130260000800199300001200207490000700219520151900226653002101745653001301766100001501779700001501794700001401809856013201823 2004 eng d00aReachability and Steering of Rolling Polyhedra: A Case Study in Discrete Nonholonomy0 aReachability and Steering of Rolling Polyhedra A Case Study in D cMay a710-7260 v493 a

Rolling a ball on a plane is a standard example of nonholonomy reported in many textbooks, and the problem is also well understood for any smooth deformation of the surfaces. For non-smoothly deformed surfaces, however, much less is known. Although it may seem intuitive that nonholonomy is conserved (think e.g. to polyhedral approximations of smooth surfaces), current definitions of ``nonholonomy'' are inherently referred to systems described by ordinary differential equations, and are thus inapplicable to such systems. \İn this paper we study the set of positions and orientations that a polyhedral part can reach by rolling on a plane through sequences of adjacent faces. We provide a description of such reachable set, discuss conditions under which the set is dense, or discrete, or has a compound structure, and provide a method for steering the system to a desired reachable configuration, robustly with respect to model uncertainties. \\Based on ideas and concepts encountered in this case study, and in some other examples we provide, we turn back to the most general aspects of the problem and investigate the possible generalization of the notion of (kinematic) nonholonomy to non-smooth, discrete, and hybrid dynamical systems. To capture the essence of phenomena commonly regarded as ``nonholonomic'', at least two irreducible concepts are to be defined, of ``internal'' and ``external'' nonholonomy, which may coexist in the same system. These definitions are instantiated by examples.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aChitour, Y1 aMarigo, A uhttp://www.centropiaggio.unipi.it/publications/reachability-and-steering-rolling-polyhedra-case-study-discrete-nonholonomy.html01230nas a2200229 4500008004100000245010300041210006900144300001400213520047100227653001300698100001800711700001500729700001300744700001600757700001900773700001400792700001600806700001300822700001300835700001500848856013700863 2004 eng d00aA Robotic Set-Up with Remote Access for ``Pick and Place'' Operations Under Uncertainty Conditions0 aRobotic SetUp with Remote Access for Pick and Place Operations U a144–1493 a

The work describes on-going work at the University of Pisa on the field of tele-laboratories and distance learning. In particular, the group is working at the evolution of existing tele-laboratory experiments in the field of robotics and control into learning units of a self-consistent didactic project. The pick-and-place system described has been designed to provide the set-up for robot arm motion planning with specific objectives and evaluation tools.

10aRobotics1 aBalestrino, A1 aBicchi, A.1 aCaiti, A1 aCecchini, T1 aPallottino, L.1 aPisani, A1 aTonietti, G1 aBorza, P1 aGomes, L1 aScutaru, G uhttp://www.centropiaggio.unipi.it/publications/robotic-set-remote-access-pick-and-place-operations-under-uncertainty-conditions.html01254nas a2200145 4500008004100000245006500041210006500106300001500171520075500186653001300941100001500954700001600969700001500985856010801000 2004 eng d00aSafe and Fast Actuators for Machines Interacting with Humans0 aSafe and Fast Actuators for Machines Interacting with Humans a(in press)3 a

This paper describes a new generation of actuators for robotic applications, and more generally for machines that are designed to interact with humans. Such actuators, called Variable Impedance Actuators, are designed to achieve fast motion control while guaranteeing safety of human operators in worst-case impact situation. The fundamental innovation is to implement safety by purely mechanical, passive means, to guarantee intrinsic safety, while active control is used to recover performance. The design concept, which is the subject of a patent application, has led to the experimental implementation of a Variable Stiffness Actuator. The effectiveness of the VSA has been recently validated theoretically and experimentally by authors.

10aRobotics1 aBicchi, A.1 aTonietti, G1 aSchiavi, R uhttp://www.centropiaggio.unipi.it/publications/safe-and-fast-actuators-machines-interacting-humans.html01703nas a2200145 4500008004100000245011100041210006900152260002500221520111100246653002101357653001301378100001501391700001501406856013601421 2004 eng d00aSome relations between ergodicity and minimality properties of invariant sets in quantized control systems0 aSome relations between ergodicity and minimality properties of i aMilanc21-22 October3 a

Linear dynamical systems controlled by quantized inputs exhibit phenomena which are typically non-linear, including chaotic behaviours. We consider discrete-time single-input models of the type x(k+1)=Ax(k)+bu(k). The construction of invariant sets for this class of hybrid systems is of utmost importance for the stabilization problem. We first review a technique to construct invariant sets when an arbitrary quantized input set is assigned. We hence study minimality properties for invariant sets when inputs take integer values. There is a relation between a so-called strong minimality property and ergodicity of the closed-loop dynamics, in particular, ergodicity implies strong minimality. A condition ensuring strong minimality is given in terms of the coefficients of the characteristic polynomial of the matrix 'A'. Two examples are presented: the first one shows that strong minimality does not imply ergodicity. The second one shows that our condition for strong minimality is only sufficient: this is done by exhibition of an ergodic dynamics for which our condition is not satisfied.

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/some-relations-between-ergodicity-and-minimality-properties-invariant-sets-quantized00603nas a2200169 4500008004100000245007200041210006900113260001700182653002100199653001300220100001400233700001800247700001600265700001700281700001500298856012000313 2003 eng d00aCooperative Simultaneous Localization and Map Building for Servoing0 aCooperative Simultaneous Localization and Map Building for Servo aPadovacJuly10aEmbedded Control10aRobotics1 aDanesi, A1 aFontanelli, D1 aMurrieri, P1 aScordio, V G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/cooperative-simultaneous-localization-and-map-building-servoing.html01245nas a2200157 4500008004100000245004300041210004300084300001400127520077800141653002100919653001300940100001500953700001400968700001500982856009000997 2003 eng d00aEncoding steering control with symbols0 aEncoding steering control with symbols a3343-33483 a

In this paper, we consider the problem of steering complex dynamical systems among equilibria in their state space in efficient ways. Efficiency is considered as the possibility of compactly representing the (typically very large, or infinite) set of reachable equilibria and quickly computing plans to move among them. To this purpose, we consider the possibility of building lattice structures by purposefully introducing quantization of inputs. We consider different ways in which control actions can be encoded in a finite or numerable set of symbols, review different applications where symbolic encoding of control actions can be employed with success, and provide a unified framework in which to study the many different possible manifestations of the idea.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aMarigo, A1 aPiccoli, B uhttp://www.centropiaggio.unipi.it/publications/encoding-steering-control-symbols.html01453nas a2200181 4500008004100000245007200041210006900113260002400182300001400206520084400220653002101064653001301085100001401098700001901112700001401131700001501145856011101160 2003 eng d00aFrom nominal to robust planning: The plate-ball manipulation system0 aFrom nominal to robust planning The plateball manipulation syste aTaipei, TaiwancMay a3175-31803 a

Robotic manipulation by rolling contacts is an appealing method for achieving dexterity with relatively simple hardware. While there exist techniques for planning motions of rigid bodies in rolling contact under nominal conditions, an inescapable challenge is the design of robust controllers of provable performance in the presence of model perturbations. As a preliminary step in this direction, we present in this paper an iterative robust planner of arbitrary accuracy for the plate-ball manipulation system subject to perturbations on the sphere radius. The basic tool is an exact geometric planner for the nominal system, whose repeated application guarantees the desired robustness property on the basis of the Iterative Steering paradigm. Simulation results under perturbed conditions show the effectiveness of the method.

10aEmbedded Control10aRobotics1 aOriolo, G1 aVendittelli, M1 aMarigo, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/nominal-robust-planning-plate-ball-manipulation-system.html00972nas a2200169 4500008004100000245010100041210006900142260001200211300001200223490000700235520035900242653002100601653001300622100001600635700001500651856013600666 2003 eng d00aNecessary and Sufficient Conditions for Robust Perfect Tracking under Variable Structure Control0 aNecessary and Sufficient Conditions for Robust Perfect Tracking  c02/2003 a141-1510 v133 a

The tracking control of linear MIMO systems with structured uncertainty is considered. A necessary and sufficient condition for robust asymptotic tracking employing variable structure techniques in the presence of multiplicative uncertainty is derived. The constructive proof of the theorem provides an explicit formula for controller synthesis.

10aEmbedded Control10aRobotics1 aBalluchi, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/necessary-and-sufficient-conditions-robust-perfect-tracking-under-variable-structure01407nas a2200157 4500008004100000245006200041210006100103300001200164520088300176653002101059653001301080100001601093700001701109700001501126856010801141 2003 eng d00aQuality of service control in soft real-time applications0 aQuality of service control in soft realtime applications a664-6693 a

In this paper we present results obtained in the context of Quality of Service (QoS) control for soft real-time applications. The discussion addresses the issue of dynamically adjusting the bandwidth for a set of periodic tasks, when a reservation-based (RB) CPU scheduling policy is used. RB techniques are particularly suitable for this kind of applications since they allow an accurate mathematical modelling of the dynamic evolution of the QoS experienced by tasks. Based on this model, a control policy guaranteeing specified QoS levels for different tasks is illustrated, along with necessary and sufficient conditions for its existence. Moreover, the problem of steering a task QoS back into its nominal level is tackled, in response to deviations due to temporary overload conditions. Simulation results are reported, for the purpose of validating the approach.

10aEmbedded Control10aRobotics1 aPalopoli, L1 aCucinotta, T1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/quality-service-control-soft-real-time-applications.html01751nas a2200205 4500008004100000245006600041210006500107260001300172300001200185520111000197653002101307653001301328100001501341700001601356700001601372700001501388700002001403700001201423856011001435 2003 eng d00aReceding-Horizon Control of LTI Systems with Quantized Inputs0 aRecedingHorizon Control of LTI Systems with Quantized Inputs bElsevier a259-2643 a

This paper deals with the stabilization problem for a particular class of hybrid systems, namely discrete-time linear systems subject to a uniform (a priori fixed) quantization of the control set. Results of our previous work on the subject provided a description of minimal (in a specific sense) invariant sets that could be rendered maximally attractive under any quantized feedback strategy. In this paper, we consider the design of stabilizing laws that optimize a given cost index on the state and input evolution on a finite, receding horizon. Application of Model Predictive Control techniques for the solution of similar hybrid control problems through Mixed Logical Dynamical reformulations can provide a stabilizing control law, provided that the feasibility hypotheses are met. In this paper, we discuss precisely what are the shortest horizon length and the minimal invariant terminal set for which it can be guaranteed a stabilizing MPC scheme. The final paper will provide an example and simulations of the application of the control scheme to a practical quantized control problem.

10aEmbedded Control10aRobotics1 aPicasso, B1 aPancanti, S1 aBemporad, A1 aBicchi, A.1 aEngell, Gueguen1 aZaytoon uhttp://www.centropiaggio.unipi.it/publications/receding-horizon-control-lti-systems-quantized-inputs.html01002nas a2200169 4500008004100000245006200041210006100103300001400164520043800178653002100616653001300637100001300650700001600663700003200679700001500711856010600726 2003 eng d00aStabilization of a class of discrete-time hybrid automata0 aStabilization of a class of discretetime hybrid automata a1147-11523 a

In this paper, the problem of stabilizing linear discrete time hybrid automata is considered. A synthesis methodology is obtained by extending to hybrid systems the stabilization techniques based on stable convex combinations, originally developed for switching systems. An algorithm to explore the candidate stabilizing controller actions is proposed and an application to an automotive engine control problem is described.

10aEmbedded Control10aRobotics1 aZoncu, M1 aBalluchi, A1 aVincentelli, Sangiovanni, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/stabilization-class-discrete-time-hybrid-automata.html01422nas a2200193 4500008004100000245008600041210006900127260004100196300001200237490001400249520074400263653002101007653001301028100001501041700001501056700001401071700001301085856013001098 2003 eng d00aStabilization of LTI Systems with Quantized State-Quantized Input Static Feedback0 aStabilization of LTI Systems with Quantized StateQuantized Input aHeidelberg, GermanybSpringer-Verlag a405-4160 vLNCS 26233 a

This paper is concerned with the stabilization problem for discrete-time linear systems subject to a uniform quantization of the control set and to a regular state quantization, both fixed a priori. As it is well known, for quantized systems only weak (practical) stability properties can be achieved. Therefore, we focus on the existence and construction of quantized controllers (mapping a quantized state into a quantized input set) capable of steering a system to within invariant neighbourhoods of the equilibrium. Such analysis is helpful because it allows to decide a priori whether adesired control objective can be achieved by using a \textit{given} technology (actuators, sensors, communication and computational means).

10aEmbedded Control10aRobotics1 aPicasso, B1 aBicchi, A.1 aPnueli, A1 aMaler, O uhttp://www.centropiaggio.unipi.it/publications/stabilization-lti-systems-quantized-state-quantized-input-static-feedback.html01083nas a2200193 4500008004100000245006600041210006600107260002000173520046200193653001300655100001500668700001600683700001400699700001800713700001700731700001400748700001300762856011400775 2003 eng d00aVariable Stiffness Actuators for Fast and Safe Motion Control0 aVariable Stiffness Actuators for Fast and Safe Motion Control bSpringer Verlag3 a

In this paper we propose Variable Stiffness actuation as a viable mechanical/control co-design approach for guaranteeing control performance for robot arms that are inherently safe to humans in their environment. A new actuator under development in our Lab is then proposed, which incorporate the possibility to vary transmission stiffness during motion execution, thus allowing substantial motion speed-up while maintaining low injury risk levels.

10aRobotics1 aBicchi, A.1 aTonietti, G1 aBavaro, M1 aPiccigallo, M1 aSiciliano, B1 aKhatib, O1 aGroen, F uhttp://www.centropiaggio.unipi.it/publications/variable-stiffness-actuators-fast-and-safe-motion-control.html01176nas a2200145 4500008004100000245007800041210006900119260001200188300001400200520064800214653001300862100001600875700001500891856012400906 2002 eng d00aAdaptive Simultaneous Position and Stiffness Control for a Soft Robot Arm0 aAdaptive Simultaneous Position and Stiffness Control for a Soft  cOctober a1992-19973 a

In this paper, an independent joint position and stiffness adaptive control for a robot arm actuated by McKibbenartificial muscles is reported. In particular, {\em muscular} nd {\em dynamic} parameters of the system are supposed unknown. Adaptive control performance is tested in a one degree of freedom experimental setup and compared with PID control performance. The adaptive control scheme is then applied to a robot arm that is conceived to perform tasks in an anthropic environment. The adaptive control developed is such that performance of the robot arm is very similar to this of human arm. Experimental results are reported.

10aRobotics1 aTonietti, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-simultaneous-position-and-stiffness-control-soft-robot-arm.html01569nas a2200181 4500008004100000245010600041210006900147260001000216300000900226490000600235520093300241653002101174653001301195100001901208700001301227700001501240856013201255 2002 eng d00aConflict Resolution Problems for Air Traffic Management Systems Solved with Mixed Integer Programming0 aConflict Resolution Problems for Air Traffic Management Systems  cMarch a3-110 v33 a

This paper considers the problem of solving conflicts arising among several aircraft that are assumed to move in a shared airspace. Aircraft can not get closer to each other than a given safety distance in order to avoid possible conflicts between different airplanes. For such system of multiple aircraft, we consider the path planning problem among given waypoints avoiding all possible conflicts. In particular we are interested in optimal paths, i.e. we want to minimize the total flight time. We propose two different formulations of the multi-aircraft conflict avoidance problem as a mixed-integer linear program: in the first case only velocity changes are admissible maneuvers, in the second one only heading angle changes are allowed. Due to the linear formulation of the two problems, solutions may be obtained quickly with standard optimization software, allowing our approach to be implemented in real time.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aFeron, E1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/conflict-resolution-problems-air-traffic-management-systems-solved-mixed-integer01663nas a2200169 4500008004100000245008500041210006900126260001300195300001200208520106100220653002101281653001301302100001501315700001801330700001501348856013001363 2002 eng d00aConstruction of invariant and attractive sets for quantized-input linear systems0 aConstruction of invariant and attractive sets for quantizedinput cDecember a824-8293 a

In this paper, the problem of the stabilization of a discrete-time linear system subject to a fixed and uniformly quantized control set is considered. It is well known that, working with quantized inputs, the states of the system (except for a negligible set of initial conditions) cannot reach asymptotically the equilibrium point. Our aim is then to find an invariant and attractive neighborhood of the equilibrium and provide with a controller which steers the system into it. We construct a continuous and increasing family of invariant sets including one which is, in a specific sense, minimal. The invariance and attractivity properties of such sets are revised in the finite control set case: we propose a family of controllers taking on a finite number of values and ensuring the system convergence to the minimal invariant set. Some consequences of our technique are underlined with particular regard to the usage of Model Predictive Control tools. In the last section an example which shows the effectiveness of our results is presented.

10aEmbedded Control10aRobotics1 aPicasso, B1 aGouaisbaut, F1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/construction-invariant-and-attractive-sets-quantized-input-linear-systems.html00447nam a2200145 4500008004100000245003300041210003300074260003900107490000600146653001300152100001500165700001900180700002000199856008200219 2002 eng d00aControl Problems in Robotics0 aControl Problems in Robotics aBerlin HeidelbergbSpringer Verlag0 v410aRobotics1 aBicchi, A.1 aChristensen, H1 aPrattichizzo, D uhttp://www.centropiaggio.unipi.it/publications/control-problems-robotics.html00566nas a2200157 4500008004100000245006400041210006400105260002800169300001200197653002100209653001300230100001600243700001800259700001500277856011600292 2002 eng d00aControllo Ibrido di Veicoli su Ruote con Retroazione Visiva0 aControllo Ibrido di Veicoli su Ruote con Retroazione Visiva aENEA, FrascaticOctober a197-19910aEmbedded Control10aRobotics1 aMurrieri, P1 aFontanelli, D1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/controllo-ibrido-di-veicoli-su-ruote-con-retroazione-visiva.html00548nas a2200133 4500008004100000245010200041210006900143260001200212300001000224653001300234100001500247700001600262856013600278 2002 eng d00aDesign, Realization and Control of Soft Robot Arms for Intrinsically Safe Interaction with Humans0 aDesign Realization and Control of Soft Robot Arms for Intrinsica cOctober a79-8710aRobotics1 aBicchi, A.1 aTonietti, G uhttp://www.centropiaggio.unipi.it/publications/design-realization-and-control-soft-robot-arms-intrinsically-safe-interaction-humans00522nas a2200145 4500008004100000245007400041210006900115260001300184300001200197490000700209653001300216100001500229700001400244856011800258 2002 eng d00aDexterous Grippers: Putting Nonholonomy to Work for Fine Manipulation0 aDexterous Grippers Putting Nonholonomy to Work for Fine Manipula cMay-June a427-4420 v2110aRobotics1 aBicchi, A.1 aMarigo, A uhttp://www.centropiaggio.unipi.it/publications/dexterous-grippers-putting-nonholonomy-work-fine-manipulation.html00483nas a2200145 4500008004100000245006200041210006200103260001300165300001200178490000700190653001300197100001500210700001200225856010000237 2002 eng d00aEditorial for the Special Issue on Nonholonomy on Purpose0 aEditorial for the Special Issue on Nonholonomy on Purpose cMay-June a387-3880 v2110aRobotics1 aBicchi, A.1 aArai, H uhttp://www.centropiaggio.unipi.it/publications/editorial-special-issue-nonholonomy-purpose.html00579nas a2200169 4500008004100000245005800041210005700099260003900156653001200195653001300207100002000220700001500240700001800255700001400273700001500287856010700302 2002 eng d00aGrasp Control: a General Manipulation System Approach0 aGrasp Control a General Manipulation System Approach aLausannebIEEE/RSJ IROScSeptember10aHaptics10aRobotics1 aPrattichizzo, D1 aBicchi, A.1 aMelchiorri, C1 aSanz, P J1 aMolfino, R uhttp://www.centropiaggio.unipi.it/publications/grasp-control-general-manipulation-system-approach.html01158nas a2200169 4500008004100000245006800041210006500109260001300174300001200187520059600199653002100795653001300816100001400829700001500843700001500858856011500873 2002 eng d00aA Group-Theoretic Characterization of Quantized Control Systems0 aGroupTheoretic Characterization of Quantized Control Systems cDecember a811-8163 a

In this paper we consider the reachability problem for quantized control systems, i.e. systems that take inputs from a finite set of symbols. Previous work addressed this problem for linear systems and for some specific classes of nonlinear driftless systems. In this paper we attack the study of more general nonlinear systems. To do so we find it useful to pose the problem in more abstract terms, and make use of the wealth of tools available in group theory, which enables us to proceed in our agenda of better understanding effects of quantization of inputs on dynamic systems.

10aEmbedded Control10aRobotics1 aMarigo, A1 aPiccoli, B1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/group-theoretic-characterization-quantized-control-systems.html01142nas a2200157 4500008004100000245005700041210005400098260000800152300001400160520064400174653002100818653001300839100001400852700001500866856010300881 2002 eng d00aA local-local planning algorithm for rolling objects0 alocallocal planning algorithm for rolling objects cMay a1759-17643 a

In this paper, we consider planning motions of objects of regular shape rolling on a plane among obstacles. Theoretical foundations and applications of this type of operations in robotic manipulation and locomotion have been discussed elsewhere. In this paper, we propose a novel algorithm that improves upon existing techniques in that: i) it is finitely computable and predictable (an upper bound on the computations necessary to reach a given goal within a tolerance can be given), and ii) it possesses a topological (local-local) property which enables obstacles and workspace limitations to be dealt with in an effective way.

10aEmbedded Control10aRobotics1 aMarigo, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/local-local-planning-algorithm-rolling-objects.html01380nas a2200169 4500008004100000245007600041210006900117260001300186300001400199520077900213653002100992653001301013100001601026700001501042700003301057856012001090 2002 eng d00aNumerically efficient control of systems with communication constraints0 aNumerically efficient control of systems with communication cons cDecember a1626-16313 a

The problem of stabilization to the trivial equilibrium of a system with communication constraints is addressed. The communication constraints are related to the fact that commands are issued to different groups of actuators through a shared resource. We tackle the problem by using a Model Predictive Control scheme, which,at every step, decides the allocation of the bus {\em and} he control command values. After discussing two different alternatives for dealing with the scheduling constraints, we develop a formulation based on the generalized linear complementarity problem, which enables the application of efficient numerical solutions. Finally, we give some preliminary result on the parametric dependence of the problem's solution from the system's state.

10aEmbedded Control10aRobotics1 aPalopoli, L1 aBicchi, A.1 aSangiovanni-Vincentelli, A L uhttp://www.centropiaggio.unipi.it/publications/numerically-efficient-control-systems-communication-constraints.html01569nas a2200217 4500008004100000245004700041210004700088260004100135300001200176490001400188520092000202653002101122653001301143100001601156700001601172700001901188700001501207700001401222700001901236856009601255 2002 eng d00aOptimal control of quantized input systems0 aOptimal control of quantized input systems aHeidelberg, GermanybSpringer-Verlag a351-3630 vLNCS 22893 a

In this paper we consider the problem of optimal control (specifically, minimum-time steering) for systems with quantized inputs. In particular, we propose a new approach to the solution of the optimal control problem for an important class of nonlinear systems, i.e. chained-form systems. By exploiting results on the structure of the reachability set of these systems under quantized control, the optimal solution is determined solving an integer linear programming problem. Our algorithm represents an improvement with respect to classical approaches in terms of exactness, as it does not resort to any a priori state-space discretization. Although the computational complexity of the problem in our formulation is still formally exponential, it lends itself to application of Branch and Bound techniques, which substantially cuts down computations in many cases, as it has been experimentally observed.

10aEmbedded Control10aRobotics1 aPancanti, S1 aLeonardi, L1 aPallottino, L.1 aBicchi, A.1 aTomlin, C1 aGreenstreet, M uhttp://www.centropiaggio.unipi.it/publications/optimal-control-quantized-input-systems.html01415nas a2200157 4500008004100000245005100041210004800092260001600140520092000156653002101076653001301097100001601110700001901126700001501145856009701160 2002 eng d00aOn Optimal Steering of Quantized Input Systems0 aOptimal Steering of Quantized Input Systems aUrbana, IL.3 a

In this paper we consider the problem of optimal control (specifically, minimum-time steering) for systems with quantized inputs. In particular, we propose a new approach to the solution of the optimal control problem for an important class of nonlinear systems, i.e. chained-form systems. By exploiting results on the structure of the reachability set of these systems under quantized control, the optimal solution is determined solving an integer linear programming problem. Our algorithm represents an improvement with respect to classical approaches in terms of exactness, as it does not resort to any a priori state-space discretization. Although the computational complexity of the problem in our formulation is still formally exponential, it lends itself to application of Branch and Bound techniques, which substantially cuts down computations in many cases, as it has been experimentally observed.

10aEmbedded Control10aRobotics1 aPancanti, S1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-steering-quantized-input-systems.html01271nas a2200181 4500008004100000245005300041210004600094260001000140300001200150490000600162520074800168653002100916653001300937100001500950700001400965700001500979856009500994 2002 eng d00aOn the reachability of quantized control systems0 areachability of quantized control systems cApril a546-5630 v43 a

In this paper we study control systems whose input sets are quantized, i.e. finite or regularly distributed on a mesh. We specifically focus on problems relating to the structure of the reachable set of such systems, which may turn out to be either dense or discrete. We report results on the reachable set of linear quantized systems, and on a particular but interesting class of nonlinear systems, i.e. nonholonomic chained-form systems. For such systems, we provide a complete characterization of the reachable set, and, in the case the set is discrete, a computable method to completely and succinctly describe its structure. Implications and open problems in the analysis and synthesis of quantized control systems are addressed.

10aEmbedded Control10aRobotics1 aBicchi, A.1 aMarigo, A1 aPiccoli, B uhttp://www.centropiaggio.unipi.it/publications/reachability-quantized-control-systems.html00601nas a2200145 4500008004100000245010300041210006900144260002800213300001200241653002100253653001300274100001900287700001500306856013400321 2002 eng d00aRisoluzione ottima dei conflitti tra agenti autonomi: applicazione al controllo del traffico aereo0 aRisoluzione ottima dei conflitti tra agenti autonomi applicazion aENEA, FrascaticOctober a193-19710aEmbedded Control10aRobotics1 aPallottino, L.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/risoluzione-ottima-dei-conflitti-tra-agenti-autonomi-applicazione-al-controllo-del01471nas a2200169 4500008004100000245009700041210006900138260000800207300001200215520085500227653002101082653001301103100001901116700001501135700001601150856013501166 2002 eng d00aSafety of a decentralized scheme for Free-Flight ATMS using Mixed Integer Linear Programming0 aSafety of a decentralized scheme for FreeFlight ATMS using Mixed cMay a742-7473 a

In this paper we consider policies for free-flight management of air traffic. We consider instantaneous and bounded heading angle deviation as conflict avoidance maneuvers. The corresponding model, resulting in a Mixed Integer Linear Programming (MILP) problem allow to solve both conflict detection and conflict resolution problems. The developed algorithm proved successful in a centralized implementation with a large number of cooperating aircraft. However, the application of such algorithm to a Free Flight environment, where cooperation can only be expected from neighboring aircraft, poses many challenges. We consider a model of the decentralized conflict resolution strategy that is based on a hybrid system, and sufficient conditions under which a 3-aircraft Free Flight MILP-based scheme guarantees safety of flight are provided.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aBicchi, A.1 aPancanti, S uhttp://www.centropiaggio.unipi.it/publications/safety-decentralized-scheme-free-flight-atms-using-mixed-integer-linear-programming00739nas a2200217 4500008004100000245006700041210006700108260004100175300001200216490001400228653002100242653001300263100001600276700001500292700003300307700001700340700001500357700001900372700001400391856011600405 2002 eng d00aSynthesis of robust control systems under resource constraints0 aSynthesis of robust control systems under resource constraints aHeidelberg, GermanybSpringer-Verlag a337-3500 vLNCS 228910aEmbedded Control10aRobotics1 aPalopoli, L1 aPinello, C1 aSangiovanni-Vincentelli, A L1 aEl-Ghaoui, L1 aBicchi, A.1 aGreenstreet, M1 aTomlin, C uhttp://www.centropiaggio.unipi.it/publications/synthesis-robust-control-systems-under-resource-constraints.html01360nas a2200205 4500008004100000245005100041210005000092260002000142300001200162490000600174520076300180653002100943653001300964100001600977700001800993700001501011700001701026700001301043856009801056 2002 eng d00aVisual-servoed parking with limited view angle0 aVisualservoed parking with limited view angle bSpringer Verlag a254-2630 v53 a

In this paper the problem of stabilizing a wheeled vehicle of unicycle type to a set point, using only visual feedback, is considered. The practically most relevant problem of keeping the tracked features in sight of the camera while maneuvering to park the vehicle is taken into account. This constraint, often neglected in the literature, combines with the nonholonomic nature of the vehicle kinematics in a challenging controller design problem. We provide an effective solution to such problem by using a combination of previous results on non-smooth control synthesis, and recently developed hybrid control techniques. Simulations and experimental results on a laboratory vehicle are reported, showing the practicality of the proposed approach.

10aEmbedded Control10aRobotics1 aMurrieri, P1 aFontanelli, D1 aBicchi, A.1 aSiciliano, B1 aDario, P uhttp://www.centropiaggio.unipi.it/publications/visual-servoed-parking-limited-view-angle.html00517nas a2200157 4500008004100000245005500041210005200096260002300148300000800171653001900179653001200198653001300210100002000223700001500243856010100258 2001 eng d00aTactile Flow: Does it exist, is it useful and how?0 aTactile Flow Does it exist is it useful and how aLucca, ItalycJuly a14210aBioengineering10aHaptics10aRobotics1 aScilingo, E. P.1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/tactile-flow-does-it-exist-it-useful-and-how.html00603nas a2200145 4500008004100000245011400041210006900155260002000224653001200244653001300256100001500269700002000284700001700304856013600321 2000 eng d00aExperimental Validation of a Psychophysical Conjecture on a Simplified Model of the Haptic Perceptual Channel0 aExperimental Validation of a Psychophysical Conjecture on a Simp bSpringer-Verlag10aHaptics10aRobotics1 aBicchi, A.1 aScilingo, E. P.1 aDe Rossi, D. uhttp://www.centropiaggio.unipi.it/publications/experimental-validation-psychophysical-conjecture-simplified-model-haptic-perceptual00567nas a2200145 4500008004100000245008100041210006900122260003400191300001400225653001300239100001600252700001600268700001500284856012200299 2000 eng d00aOptimal Feedback Control for Route Tracking with a Bounded-Curvature Vehicle0 aOptimal Feedback Control for Route Tracking with a BoundedCurvat aSan Francisco, CA, USAcApril a2473-247810aRobotics1 aSouères, P1 aBalluchi, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/optimal-feedback-control-route-tracking-bounded-curvature-vehicle.html00959nas a2200169 4500008004100000245004100041210004100082260000900123300001200132520047300144653002100617653001300638100001900651700001800670700001500688856008600703 2000 eng d00aShortest paths for teams of vehicles0 aShortest paths for teams of vehicles cJune a124-1293 a

In this paper we consider the problem of planning motions of a team of vehicles that move in a planar environment. Each vehicle is modelled as a kinematic system with velocity constraints and curvature bounds. Vehicles can not get closer to each other than a predefined safety distance. When manipulating a common object cooperatively, further constraints apply. For such systems, we consider the problem of planning optimal paths in the absence of obstacles.

10aEmbedded Control10aRobotics1 aPallottino, L.1 aParlangeli, G1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/shortest-paths-teams-vehicles.html00666nas a2200169 4500008004100000245010000041210006900141260004800210300001200258653002100270653001300291100001500304700001500319700001200334700001400346856013600360 1999 eng d00aAn experimental study of performance and fault tolerance of a hybrid free-flight control scheme0 aexperimental study of performance and fault tolerance of a hybri aBerlin Heidelberg, GermanybSpringer Verlag a449-46310aEmbedded Control10aRobotics1 aBicchi, A.1 aGarulli, A1 aTesi, A1 aVicino, A uhttp://www.centropiaggio.unipi.it/publications/experimental-study-performance-and-fault-tolerance-hybrid-free-flight-control-scheme01299nas a2200169 4500008004100000245006800041210006800109260002000177520071900197653001900916653001200935653001300947100001500960700001700975700002000992856011701012 1999 eng d00aPsychophysical Evaluation of Simplified Haptic Perception Media0 aPsychophysical Evaluation of Simplified Haptic Perception Media aPisacSeptember3 a

Detection of softness by tactile exploration in humans is based on both kinesthetic and cutaneous perception, and haptic displays should be designed so as to address such multimodal perceptual channel. Unfortunately, accurate detection and replication of cutaneous information in all its details is difficlt and costly. In this paper we discuss a simplified model of haptic detection of softness (whereby only information on the rate of spread of the contact area between the finger and the specimen as the contact force increases is transmitted). We provide a thorough set of psychophysical tests, to support the feasibility (in at least some contexts) of a reduced-complicacy display of haptic features.

10aBioengineering10aHaptics10aRobotics1 aBicchi, A.1 aDe Rossi, D.1 aScilingo, E. P. uhttp://www.centropiaggio.unipi.it/publications/psychophysical-evaluation-simplified-haptic-perception-media.html01763nas a2200181 4500008004100000245007800041210006900119300001200188520115100200653001901351653001201370653001301382100001501395700001501410700001701425700002001442856011901462 1999 eng d00aThe Role of Contact Area Spread Rate in Haptic Discrimination of Softness0 aRole of Contact Area Spread Rate in Haptic Discrimination of Sof a305-3103 a

Many applications in teleoperation and virtual reality call for the implementation of effective means of displaying to the human operator information on the softness and other mechanical properties of objects being touched. The ability of humans to detect softness of different objects by tactual exploration is intimately related to both kinesthetic and cutaneous perception, and haptic displays should be designed so as to address such multimodal perceptual channel. Unfortunately, accurate detection and replication of cutaneous information in all its details appears to be a formidable task for current technology, causing most of today's haptic displays to merely address the kinesthetic part of haptic information. In this paper we investigate the possibility of surrogating detailed tactile information for softness discrimination, with information on the rate of spread of the contact area between the finger and the specimen. Devices for implementing this new perceptual channel are described, and some preliminary psychophysical test results are reported, validating the effectiveness and practicality of the proposed approach.

10aBioengineering10aHaptics10aRobotics1 aAmbrosi, G1 aBicchi, A.1 aDe Rossi, D.1 aScilingo, E. P. uhttp://www.centropiaggio.unipi.it/publications/role-contact-area-spread-rate-haptic-discrimination-softness.html-000526nas a2200145 4500008004100000245006300041210006300104653002100167653001300188100002000201700001800221700001500239700001400254856011200268 1998 eng d00aActive Suspensions Decoupling by Algebraic Output Feedback0 aActive Suspensions Decoupling by Algebraic Output Feedback10aEmbedded Control10aRobotics1 aPrattichizzo, D1 aMercorelli, P1 aBicchi, A.1 aVicino, A uhttp://www.centropiaggio.unipi.it/publications/active-suspensions-decoupling-algebraic-output-feedback.html00639nas a2200181 4500008004100000245008300041210006900124260001400193300001400207653001900221653001200240653001300252100002000265700001500285700001700300700001500317856012500332 1998 eng d00aHaptic display able to replicate the rheological behaviour of surgical tissues0 aHaptic display able to replicate the rheological behaviour of su aHong Kong a1738-174110aBioengineering10aHaptics10aRobotics1 aScilingo, E. P.1 aBicchi, A.1 aDe Rossi, D.1 aIacconi, P uhttp://www.centropiaggio.unipi.it/publications/haptic-display-able-replicate-rheological-behaviour-surgical-tissues.html00478nas a2200133 4500008004100000245006000041210005900101653001200160653001300172100001500185700002000200700001800220856010600238 1998 eng d00aOptimization of Internal Forces in Force-Closure Grasps0 aOptimization of Internal Forces in ForceClosure Grasps10aHaptics10aRobotics1 aBicchi, A.1 aPrattichizzo, D1 aAntognetti, G uhttp://www.centropiaggio.unipi.it/publications/optimization-internal-forces-force-closure-grasps.html00533nas a2200157 4500008004100000245005800041210005800099260002000157653001200177653001300189100002000202700001800222700001500240700001400255856010600269 1997 eng d00aGeometric Control Techniques for Manipulation Systems0 aGeometric Control Techniques for Manipulation Systems aBelfort, France10aHaptics10aRobotics1 aPrattichizzo, D1 aMercorelli, P1 aBicchi, A.1 aVicino, A uhttp://www.centropiaggio.unipi.it/publications/geometric-control-techniques-manipulation-systems.html00556nas a2200157 4500008004100000245005600041210005600097260004900153653001200202653001300214100002000227700001800247700001500265700001400280856010400294 1997 eng d00aGeometric Control Techniques for Mechanical Systems0 aGeometric Control Techniques for Mechanical Systems aSiena, Italia, september 29 - October 3 199710aHaptics10aRobotics1 aPrattichizzo, D1 aMercorelli, P1 aBicchi, A.1 aVicino, A uhttp://www.centropiaggio.unipi.it/publications/geometric-control-techniques-mechanical-systems.html00658nas a2200169 4500008004100000245011700041210006900158260001100227653001900238653001200257653001300269100002000282700001700302700001500319700001500334856013900349 1997 eng d00aHaptic display for replication of rheological behaviour of surgical tissues: modelling, control, and experiments0 aHaptic display for replication of rheological behaviour of surgi aDallas10aBioengineering10aHaptics10aRobotics1 aScilingo, E. P.1 aDe Rossi, D.1 aBicchi, A.1 aIaccone, P uhttp://www.centropiaggio.unipi.it/publications/haptic-display-replication-rheological-behaviour-surgical-tissues-modelling-control-and00456nas a2200133 4500008004100000245005100041210005000092260002000142653001300162100001500175700001300190700002000203856009900223 1997 eng d00aOptimal Design of Dynamic Force/Torque Sensors0 aOptimal Design of Dynamic ForceTorque Sensors aBelfort, France10aRobotics1 aBicchi, A.1 aCaiti, A1 aPrattichizzo, D uhttp://www.centropiaggio.unipi.it/publications/optimal-design-dynamic-forcetorque-sensors.html00551nas a2200181 4500008004100000245003800041210003800079260004800117300001000165653001200175653001300187100001500200700001400215700002000229700001700249700001700266856008600283 1997 eng d00aRobotic Dexterity via Nonholonomy0 aRobotic Dexterity via Nonholonomy aBerlin Heidelberg, GermanybSpringer Verlag a35-4910aHaptics10aRobotics1 aBicchi, A.1 aMarigo, A1 aPrattichizzo, D1 aSiciliano, B1 aValavanis, K uhttp://www.centropiaggio.unipi.it/publications/robotic-dexterity-nonholonomy.html00648nas a2200193 4500008004100000245006400041210006300105260004000168300001200208653002100220653001300241100001500254700001400269700002000283700001500303700001700318700001600335856010300351 1997 eng d00aRolling Polyhedra on a Plane: Analysis of the Reachable Set0 aRolling Polyhedra on a Plane Analysis of the Reachable Set aWellesley, MA, U.S.A.bA. K. Peters a277-28610aEmbedded Control10aRobotics1 aChitour, Y1 aMarigo, A1 aPrattichizzo, D1 aBicchi, A.1 aLaumond, J P1 aOvermars, M uhttp://www.centropiaggio.unipi.it/publications/rolling-polyhedra-plane-analysis-reachable-set.html00694nas a2200205 4500008004100000245006600041210006300107260004100170300001200211653001200223653001300235100001500248700002000263700001500283700002000298700001800318700002400336700001600360856011200376 1997 eng d00aOn some structural properties of general manipulation systems0 asome structural properties of general manipulation systems aLondon, U.K.bImperial College Press a187-20210aHaptics10aRobotics1 aBicchi, A.1 aPrattichizzo, D1 aAstolfi, A1 aLimebeer, D J N1 aMelchiorri, C1 aTornambèe, A1 aVinter, R B uhttp://www.centropiaggio.unipi.it/publications/some-structural-properties-general-manipulation-systems.html00593nas a2200205 4500008004100000245003400041210003400075260004800109300001000157653001200167653001300179100001500192700001400207700002000221700001500241700001700256700001800273700001300291856008300304 1996 eng d00aReachability of Rolling Parts0 aReachability of Rolling Parts aSingaporebWorld Scientific Publisher Corp. a51-6010aHaptics10aRobotics1 aChitour, Y1 aMarigo, A1 aPrattichizzo, D1 aBicchi, A.1 aBonivento, C1 aMelchiorri, C1 aTolle, H uhttp://www.centropiaggio.unipi.it/publications/reachability-rolling-parts.html00460nas a2200133 4500008004100000022001600041245005600057210005600113260001000169653001300179100001500192700001500207856010400222 1995 eng d aFI95A00010800aCalibration technique for Intrinsic Tactile Sensors0 aCalibration technique for Intrinsic Tactile Sensors aItaly10aRobotics1 aBicchi, A.1 aGranata, F uhttp://www.centropiaggio.unipi.it/publications/calibration-technique-intrinsic-tactile-sensors.html00442nas a2200145 4500008004100000245005000041210004300091260001100134300001200145490000700157653001200164653001300176100001500189856009200204 1995 eng d00aOn the Closure Properties of Robotic Grasping0 aClosure Properties of Robotic Grasping cAugust a319-3340 v1410aHaptics10aRobotics1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/closure-properties-robotic-grasping.html00405nas a2200133 4500008004100000245004600041210004500087300001200132653001200144653001300156100001500169700002000184856006700204 1994 eng d00aControllability of whole-arm manipulation0 aControllability of wholearm manipulation a373-37410aHaptics10aRobotics1 aBicchi, A.1 aPrattichizzo, D uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=41090000543nas a2200133 4500008004100000245010000041210006900141300001200210490000700222653001300229653001300242100001500255856013900270 1994 eng d00aOn the Problem of Decomposing Grasp and Manipulation Forces in Multiple Whole-Limb Manipulation0 aProblem of Decomposing Grasp and Manipulation Forces in Multiple a127-1470 v1310aGrasping10aRobotics1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/problem-decomposing-grasp-and-manipulation-forces-multiple-whole-limb-manipulation.html00670nas a2200169 4500008004100000245010000041210006900141260004800210653001200258653001300270100001500283700001900298700001500317700001500332700001700347856013600364 1993 eng d00aExperimental Evaluation of Friction Data with an Articulated Hand and Intrinsic Contact Sensors0 aExperimental Evaluation of Friction Data with an Articulated Han aBerlin Heidelberg, GermanybSpringer Verlag10aHaptics10aRobotics1 aBicchi, A.1 aSalisbury, J K1 aBrock, D L1 aChatila, R1 aHirzinger, G uhttp://www.centropiaggio.unipi.it/publications/experimental-evaluation-friction-data-articulated-hand-and-intrinsic-contact-sensors00385nas a2200121 4500008004100000245004800041210004800089653001200137653001300149100001500162700001800177856006800195 1993 eng d00aManipulability Measures of Cooperating Arms0 aManipulability Measures of Cooperating Arms10aHaptics10aRobotics1 aBicchi, A.1 aMelchiorri, C uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=479286700628nas a2200169 4500008004100000245008700041210006900128260002900197300001300226653001200239653001300251100001500264700002000279700001600299700001600315856012700331 1993 eng d00aNew Issues in the Kineto-Statics, Dynamics, and Control of Whole-Hand Manipulation0 aNew Issues in the KinetoStatics Dynamics and Control of WholeHan aAmsterdambNorth Holland a373-379010aHaptics10aRobotics1 aBicchi, A.1 aPrattichizzo, D1 aTakamori, T1 aTsuchiya, K uhttp://www.centropiaggio.unipi.it/publications/new-issues-kineto-statics-dynamics-and-control-whole-hand-manipulation.html00574nas a2200157 4500008004100000022001800041245006000059210006000119260004500179653002100224653001300245100002000258700001500278700001600293856010700309 1993 eng d aO-88986-179-X00aStatically Stable Legged Locomotion with Leg Redundancy0 aStatically Stable Legged Locomotion with Leg Redundancy aOxford, UK, september 23-25 1993bIASTED10aEmbedded Control10aRobotics1 aPrattichizzo, D1 aBicchi, A.1 aCasalino, G uhttp://www.centropiaggio.unipi.it/publications/statically-stable-legged-locomotion-leg-redundancy.html00576nas a2200145 4500008004100000245008000041210006900121260003800190653001300228100001800241700001500259700001300274700002000287856012300307 1993 eng d00aA variable structure approach to force/motion control of robot manipulators0 avariable structure approach to forcemotion control of robot mani aMilan, Italy, November 23-25 199310aRobotics1 aBalestrino, A1 aBicchi, A.1 aLandi, A1 aPrattichizzo, D uhttp://www.centropiaggio.unipi.it/publications/variable-structure-approach-forcemotion-control-robot-manipulators.html00667nas a2200169 4500008004100000245010600041210006900147260004800216653001200264653001300276100001500289700001500304700001300319700001700332700001500349856013300364 1993 eng d00aWhole Hand Manipulation: Design of an Articulated Hand Exploiting All Its Parts To Increase Dexterity0 aWhole Hand Manipulation Design of an Articulated Hand Exploiting aBerlin Heidelberg, GermanybSpringer Verlag10aHaptics10aRobotics1 aVassura, G1 aBicchi, A.1 aDario, P1 aAebischer, P1 aSandini, G uhttp://www.centropiaggio.unipi.it/publications/whole-hand-manipulation-design-articulated-hand-exploiting-all-its-parts-increase00570nas a2200157 4500008004100000245006500041210006500106260003200171653001300203100001900216700001500235700001900250700001300269700001700282856011300299 1992 eng d00aAdaptive neural state observer for unknown non linear plants0 aAdaptive neural state observer for unknown non linear plants aKobe, Japan, Sep 16-20 199210aRobotics1 aBini Verona, F1 aBicchi, A.1 aDe Gasperis, G1 aLandi, A1 aSilvestri, G uhttp://www.centropiaggio.unipi.it/publications/adaptive-neural-state-observer-unknown-non-linear-plants.html00557nas a2200169 4500008004100000245004900041210004900090260004800139653001200187653001300199100001300212700001800225700001500243700001600258700001600274856009700290 1992 eng d00aMultiple Sensing for Dexterous End Effectors0 aMultiple Sensing for Dexterous End Effectors aBerlin Heidelberg, GermanybSpringer Verlag10aHaptics10aRobotics1 aDario, P1 aBergamasco, M1 aBicchi, A.1 aFiorillo, A1 aBejczy, A K uhttp://www.centropiaggio.unipi.it/publications/multiple-sensing-dexterous-end-effectors.html00608nas a2200169 4500008004100000245007200041210006900113260003900182300001200221653001300233100001500246700001800261700001300279700001400292700001500306856011700321 1992 eng d00aQuasi-Static Compensation of Force Errors for Flexible Manipulators0 aQuasiStatic Compensation of Force Errors for Flexible Manipulato aOxford, U.K.bPergamon Press Books a381-38510aRobotics1 aBicchi, A.1 aMelchiorri, C1 aTroch, I1 aDesoer, K1 aKopacek, P uhttp://www.centropiaggio.unipi.it/publications/quasi-static-compensation-force-errors-flexible-manipulators.html00470nas a2200157 4500008004100000245002900041210002900070260004800099653001200147653001300159100001600172700001500188700001300203700001500216856008100231 1992 eng d00aRobot Tactile Perception0 aRobot Tactile Perception aBerlin Heidelberg, GermanybSpringer Verlag10aHaptics10aRobotics1 aButtazzo, G1 aBicchi, A.1 aDario, P1 aLee, C S G uhttp://www.centropiaggio.unipi.it/publications/robot-tactile-perception.html00543nas a2200145 4500008004100000245007300041210006900114260001700183653002100200653001300221100001800234700001500252700001300267856011700280 1992 eng d00aTrajectory Planning of Industrial Robots in a Structured Environment0 aTrajectory Planning of Industrial Robots in a Structured Environ aMetz, France10aEmbedded Control10aRobotics1 aBalestrino, A1 aBicchi, A.1 aLandi, A uhttp://www.centropiaggio.unipi.it/publications/trajectory-planning-industrial-robots-structured-environment.html00527nas a2200145 4500008004100000245006200041210006000103260003700163653001200200653001300212100001500225700001600240700001700256856010800273 1991 eng d00aRobotic Tactile Sensing: Skin-like and Intrinsic Approach0 aRobotic Tactile Sensing Skinlike and Intrinsic Approach aNew York, NY, USAbMarcel Dekker10aHaptics10aRobotics1 aBicchi, A.1 aButtazzo, G1 aTzafestas, S uhttp://www.centropiaggio.unipi.it/publications/robotic-tactile-sensing-skin-and-intrinsic-approach.html00630nas a2200205 4500008004100000245005100041210005100092260004800143300001000191490000700201653001200208653001300220100001800233700001300251700001500264700001600279700001300295700001700308856009900325 1990 eng d00aMulti Sensor Integration for Fine Manipulation0 aMulti Sensor Integration for Fine Manipulation aBerlin Heidelberg, GermanybSpringer Verlag a55-660 v5810aHaptics10aRobotics1 aBergamasco, M1 aDario, P1 aBicchi, A.1 aButtazzo, G1 aTou, J T1 aBalchen, J G uhttp://www.centropiaggio.unipi.it/publications/multi-sensor-integration-fine-manipulation.html00538nas a2200133 4500008004100000245008200041210006900123260002000192653001200212653001300224100001800237700001500255856013400270 1989 eng d00aAdaptive Surface Following and Reconstruction Using Intrinsic Tactile Sensing0 aAdaptive Surface Following and Reconstruction Using Intrinsic Ta aZaragoza, Spain10aHaptics10aRobotics1 aBalestrino, A1 aBicchi, A. uhttp://www.centropiaggio.unipi.it/publications/adaptive-surface-following-and-reconstruction-using-intrinsic-tactile-sensing.html00578nas a2200181 4500008004100000245007500041210006900116260001900185653002100204653001300225100001500238700001300253700001300266700001700279700001600296700001700312856006700329 1989 eng d00aLeg-Ankle-Foot System for Investigating Sensor Based Legged Locomotion0 aLegAnkleFoot System for Investigating Sensor Based Legged Locomo aTsukuba, Japan10aEmbedded Control10aRobotics1 aBicchi, A.1 aBosio, L1 aDario, P1 aGuiggiani, M1 aManfredi, E1 aPinotti, P C uhttp://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=63797000535nas a2200169 4500008004100000245005100041210005100092260003400143300001000177653001200187653001300199100001500212700001300227700001400240700001200254856009900266 1988 eng d00aIntrinsic Tactile Sensing for Artificial Hands0 aIntrinsic Tactile Sensing for Artificial Hands aCambridge, MA, USAbMIT Press a83-9010aHaptics10aRobotics1 aBicchi, A.1 aDario, P1 aBolles, R1 aRoth, B uhttp://www.centropiaggio.unipi.it/publications/intrinsic-tactile-sensing-artificial-hands.html00662nas a2200193 4500008004100000245006600041210006400107260005700171300001200228653001200240653001300252100001300265700001500278700001600293700001600309700001900325700001500344856010900359 1986 eng d00aA Sensorized Scenario for Basic Investigation on Active Touch0 aSensorized Scenario for Basic Investigation on Active Touch aKempston, Bedford, U. K.bI. F. S. Publications Ltd. a237-24510aHaptics10aRobotics1 aDario, P1 aBicchi, A.1 aFiorillo, A1 aButtazzo, G1 aFrancesconi, R1 aPugh, Alan uhttp://www.centropiaggio.unipi.it/publications/sensorized-scenario-basic-investigation-active-touch.html00575nas a2200145 4500008003900000245008800039210006900127260004000196653001200236653001300248100001500261700001300276700001700289856012300306 1985 d00aOn the Control of a Sensorized Artificial Finger for Tactile Exploration of Objects0 aControl of a Sensorized Artificial Finger for Tactile Exploratio aBarcelona, Spain, 6-8 November 198510aHaptics10aRobotics1 aBicchi, A.1 aDario, P1 aPinotti, P C uhttp://www.centropiaggio.unipi.it/publications/control-sensorized-artificial-finger-tactile-exploration-objects.html-000630nas a2200181 4500008004100000245008000041210006900121260002400190653001200214653001600226653001300242653001200255100001300267700001500280700001500295700001700310856012100327 1985 eng d00aTendon Actuated Exploratory Finger With Polymeric, Skin-like Tactile Sensor0 aTendon Actuated Exploratory Finger With Polymeric Skinlike Tacti aSt. Louis, MO, USA.10aHaptics10aRobot Hands10aRobotics10aSensors1 aDario, P1 aBicchi, A.1 aVivaldi, F1 aPinotti, P C uhttp://www.centropiaggio.unipi.it/publications/tendon-actuated-exploratory-finger-polymeric-skin-tactile-sensor.html