@article {3326, title = {Decentralized Trajectory Tracking Control for Soft Robots Interacting with the Environment}, journal = {IEEE Transactions on Robotics (T-RO).}, volume = {Early Access}, year = {2018}, month = {06/2018}, abstract = {

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.

}, keywords = {Robotics}, author = {F. Angelini and C. Della Santina and M. Garabini and M. Bianchi and G M Gasparri and G. Grioli and M. G. Catalano and A. Bicchi} } @article {3119, title = {Controlling Soft Robots: Balancing Feedback and Feedforward Elements}, journal = {IEEE Robotics and Automation Magazine}, volume = {24}, year = {2017}, note = {

This work is supported by European Commission grant H2020-ICT-645599 ({\textquotedblleft}SOMA{\textquotedblright}: SOft Manipulation) and European Research Council Advanced grant 291166 ({\textquotedblleft}SoftHands{\textquotedblright}).

}, month = {05/2017}, pages = {75 - 83}, abstract = {

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{\textemdash}e.g., high-gain robust control, feedback linearization, backstepping, and active impedance control{\textemdash}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.

}, keywords = {Robotics}, issn = {1070-9932}, doi = {10.1109/MRA.2016.2636360}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7930438}, author = {C. Della Santina and M. Bianchi and G. Grioli and F. Angelini and M. G. Catalano and M. Garabini and A. Bicchi} } @conference {3218, title = {Design and characterization of a novel high-compliance spring for robots with soft joints}, booktitle = {IEEE International Conference on Advanced Intelligent Mechatronics (AIM)}, year = {2017}, publisher = {IEEE}, organization = {IEEE}, address = {Munich, Germany, 3-7 July 2017}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/AIM.2017.8014029}, url = {http://ieeexplore.ieee.org/document/8014029/}, author = {F. Negrello and M. G. Catalano and M. Garabini and M. Poggiani and D. G. Caldwell and N. G. Tsagarakis and A. Bicchi} } @conference {3219, title = {Design, control and validation of the variable stiffness exoskeleton FLExo}, booktitle = {International Conference on Rehabilitation Robotics (ICORR)}, year = {2017}, pages = {539 - 546}, publisher = {IEEE}, organization = {IEEE}, address = {London, UK, 17-20 July 2017}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/ICORR.2017.8009304}, url = {http://ieeexplore.ieee.org/document/8009304/}, author = {S. Mghames and M. Laghi and C. Della Santina and M. Garabini and M. G. Catalano and G. Grioli and A. Bicchi} } @article {2875, title = {The Quest for Natural Machine Motion: An Open Platform to Fast-Prototyping Articulated Soft Robots}, journal = {IEEE Robotics and Automation Magazine }, volume = {24}, year = {2017}, note = {

Open access

e wish to thank Samuele Batazzi, Fabio Bonomo, Alberto
Brando, Andrea Di Basco, Tommaso Pardi, Riccardo Persichi-
ni, and Alessandro Raugi for their valuable support in the
development of the hardware prototype. This work was sup-
ported by SOFTPRO (grant 688857) and SOMA (grant
645599){\textemdash}projects of the European Commission{\textquoteright}s Horizon
2020 research program{\textemdash}and by Walk-Man grant 611832.
Support also came from the European Research Council
under an Advanced Grant for {\textquotedblleft}SoftHands: A Theory of Soft
Synergies for a New Generation of Artificial Hands{\textquotedblright} (grant
ERC-291166).
}, pages = {48 - 56}, abstract = {
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.
}, keywords = {Robotics}, issn = {1070-9932 }, doi = {10.1109/MRA.2016.2636366}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7857692}, author = {C. Della Santina and C. Piazza and Gasparri, G. M. and M. Bonilla and M. G. Catalano and G. Grioli and M. Garabini and A. Bicchi} } @article {3137, title = {WALK-MAN: A High-Performance Humanoid Platform for Realistic Environments}, journal = {Journal of Field Robotics}, volume = {34}, year = {2017}, month = {06/2017}, pages = {1 - 34}, abstract = {

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.

}, keywords = {Robotics}, issn = {1556-4967}, doi = {10.1002/rob.21702}, url = {http://onlinelibrary.wiley.com/doi/10.1002/rob.21702/epdf}, author = {N. G. Tsagarakis and D. G. Caldwell and F. Negrello and W. Choi and L. Baccelliere and V. G. Loc and J. Noorden and L. Muratore and A. Margan and A. Cardellino and L. Natale and E. Mingo Hoffman and H. Dallali and N. Kashiri and J. Malzahn and J. Lee and P. Kryczka and D. Kanoulas and M. Garabini and M. G. Catalano and M. Ferrati and V. Varricchio and L. Pallottino and C. Pavan and A. Bicchi and A Settimi and A. Rocchi and A. Ajoudani} } @conference {2545, title = {A Modular Compliant Actuator for Emerging High Performance and Fall-Resilient Humanoids}, booktitle = {15th IEEE RAS Humanoids Conference (HUMANOIDS2015)}, year = {2016}, note = {

This work is supported by the WALK-MAN FP7-ICT-2013-10 European Commission project.

}, publisher = {IEEE}, organization = {IEEE}, keywords = {Robotics}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7363567}, author = {F. Negrello and M. Garabini and M. G. Catalano and J. Malzahn and D. G. Caldwell and A. Bicchi and N. G. Tsagarakis} } @conference {2889, title = {Robust Optimization of System Compliance for Physical Interaction in Uncertain Scenarios}, booktitle = {IEEE International Conference on Humanoid Robots (HUMANOIDS2016)}, year = {2016}, note = {
This work was supported by the European Commission projects (FP7 framework) Walk-Man and the European Commission Grant no. H2020- ICT-645599 {\textquotedblleft}SOMA{\textquotedblright}: SOft MAnipulation
}, publisher = {IEEE}, organization = {IEEE}, address = {Cancun, Mexico, 15-17 Nov. 2016 }, abstract = {

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.

}, keywords = {Robotics}, isbn = {978-1-5090-4718-5 }, doi = { 10.1109/HUMANOIDS.2016.7803381}, url = {http://ieeexplore.ieee.org/document/7803381/}, author = {Gasparri, G. M. and F. Fabiani and M. Garabini and L. Pallottino and M. G. Catalano and G. Grioli and R. Persichini and A. Bicchi} } @conference {3086, title = {Soft Robots that Mimic the Neuromusculoskeletal System}, booktitle = {3rd International Conference on NeuroRehabilitation (ICNR2016)}, volume = {Converging Clinical and Engineering Research on Neurorehabilitation}, year = {2016}, month = {10/2016}, pages = {259-263}, publisher = {Springer}, organization = {Springer}, abstract = {

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.

}, keywords = {Robotics}, doi = { 10.1007/978-3-319-46669-9_45}, url = {http://link.springer.com/chapter/10.1007/978-3-319-46669-9_45}, author = {M. Garabini and C. Della Santina and M. Bianchi and M. G. Catalano and G. Grioli and A. Bicchi} } @conference {2725, title = {SoftHand Pro-D: Matching Dynamic Content of Natural User Commands with Hand Embodiment for Enhanced Prosthesis Control}, booktitle = {IEEE International Conference of Robotics and Automation (ICRA2016)}, year = {2016}, note = {

softpro soma softhands

}, pages = {3516 - 3523}, publisher = {IEEE}, organization = {IEEE}, address = {Stockholm, Sweden, May 16-21}, abstract = {

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

}, keywords = {Haptics, Robotics}, doi = {10.1109/ICRA.2016.7487532}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7487532}, author = {C. Piazza and C. Della Santina and M. G. Catalano and G. Grioli and M. Garabini and A. Bicchi} } @conference {2881, title = {Toward an Adaptive Foot for Natural Walking}, booktitle = {International Conference on Humanoid Robots (HUMANOIDS2016)}, year = {2016}, address = {Cancun, Mexico, November 15-17, 2016}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/HUMANOIDS.2016.7803423}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7803423}, author = {C. Piazza and C. Della Santina and Gasparri, G. M. and M. G. Catalano and G. Grioli and M. Garabini and A. Bicchi} } @conference {2788, title = { WALK-MAN humanoid lower body design optimization for enhanced physical performance}, booktitle = {IEEE International Conference of Robotics and Automation (ICRA2016)}, year = {2016}, pages = {1817 - 1824}, publisher = {IEEE}, organization = {IEEE}, address = {Stockholm, Sweden, May 16-21, 2016 }, abstract = {
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.
}, keywords = {Robotics}, doi = {10.1109/ICRA.2016.7487327}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7487327}, author = {F. Negrello and M. Garabini and M. G. Catalano and P. Kryczka and W. Choi and D. G. Caldwell and A. Bicchi and N. G. Tsagarakis} } @conference {2478, title = {Potential merits for space robotics from novel concepts of actuation for soft robotics}, booktitle = {Advanced Space Technologies for Robotics and Automation (ASTRA) }, year = {2015}, address = {Noordwijk, The Netherlands May 11-13, 2015}, keywords = {Robotics}, author = {G. Mathijssen and S. Terryn and R. Funemont and M. Garabini and M. G. Catalano and G. Grioli and D. Lefeber and A. Bicchi and B. Vanderborght} } @conference {2543, title = {Soft Actuation in Cyclic Motions: Stiffness Profile Optimization for Energy Efficiency}, booktitle = {15th IEEE RAS Humanoids Conference (HUMANOIDS2015)}, year = {2015}, note = {

saphari walkman

}, pages = {107 - 113}, publisher = {IEEE}, organization = {IEEE}, abstract = {
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.
}, keywords = {Robotics}, doi = {10.1109/HUMANOIDS.2015.7363522}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7363522}, author = {A. Velasco and M. Garabini and M. G. Catalano and A. Bicchi} } @article {2080, title = {Variable Stiffness Actuators: the user{\textquoteright}s point of view}, journal = {Int. J. Robotics Research}, volume = {34}, year = {2015}, note = {

Extensions.zip

}, month = {05/2015}, pages = {727-743}, keywords = {Robotics}, doi = {10.1177/0278364914566515}, url = {http://ijr.sagepub.com/cgi/reprint/0278364914566515v1.pdf?ijkey=anmgudvoLz7ZloP\&keytype=finite}, author = {G. Grioli and S. Wolf and M. Garabini and M. G. Catalano and E. Burdet and D. G. Caldwell and R. Carloni and W. Friedl and M. Grebenstein and M. Laffranchi and D. Lefeber and S. Stramigioli and N G Tsagarakis and M. Van Damme and B. Vanderborght and A Albu-Schaeffer and A. Bicchi} } @conference {2450, title = {Variable Stiffness Control for Oscillation Damping}, booktitle = {IEEE International Conference of Intelligent Robots and Systems (IROS2015)}, year = {2015}, note = {
This work is supported by the EC under the grant agreements no.611832 Walk-Man and ICT-287513 {\textquotedblleft}SAPHARI{\textquotedblright}
}, pages = {6543 - 6550}, publisher = {IEEE}, organization = {IEEE}, address = {Hamburg, Germany, September 28 - October 02, 2015}, keywords = {Robotics}, doi = {10.1109/IROS.2015.7354312}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7354312}, author = {G M Gasparri and M. Garabini and L. Pallottino and L. Malagia and M. G. Catalano and G. Grioli and A. Bicchi} } @conference {2113, title = {Drum Stroke Variation Using Variable Stiffness Actuators}, booktitle = {IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2014)}, year = {2014}, pages = {3892 - 3897 }, publisher = {IEEE}, organization = {IEEE}, address = {Chicago, IL, USA}, abstract = {

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{\textquoteright}s response also changes. We implemented the specific stroke which is called {\textquotedblleft}double stroke{\textquotedblright} using 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.

}, keywords = {Robotics}, doi = {10.1109/IROS.2014.6943109}, author = {Y. Kim and M. Garabini and J. Park and A. Bicchi} } @conference {2232, title = {Grasping with Soft Hands}, booktitle = {IEEE-RAS International Conference on Humanoid Robots (HUMANOIDS 2014)}, year = {2014}, pages = {581 - 587}, address = {Madrid, Spain, November 18 - 20}, abstract = {

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 {\textemdash} in the sense of low number of actuated degrees of freedom (one for the Pisa/IIT SoftHand) {\textemdash} 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.

}, keywords = {Haptics, Robotics}, doi = {10.1109/HUMANOIDS.2014.7041421}, url = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=\&arnumber=7041421\&queryText\%3DGrasping+with+Soft+Hands}, author = {M. Bonilla and E. Farnioli and C. Piazza and M. G. Catalano and G. Grioli and M. Garabini and M Gabiccini and A. Bicchi} } @conference {2151, title = {Open Source VSA-CubeBots for Rapid Soft Robot Prototyping }, booktitle = { Robot Makers - Workshop in conjunction with 2014 Robotics Science and Systems}, year = {2014}, address = { July 12, 2014, Berkeley, California }, keywords = {Robotics}, author = {K. Melo and M. Garabini and G. Grioli and M. G. Catalano and L. Malagia and A. Bicchi} } @conference {1667, title = {Controlling the active surfaces of the Velvet Fingers: sticky to slippy fingers}, booktitle = {IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2013}, year = {2013}, month = {November 3-7}, pages = {5494 - 5499}, address = {Tokyo, Japan}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/IROS.2013.6697152}, url = {http://ieeexplore.ieee.org/xpl/login.jsp?tp=\&arnumber=6697152\&url=http\%3A\%2F\%2Fieeexplore.ieee.org\%2Fxpls\%2Fabs_all.jsp\%3Farnumber\%3D6697152}, author = {V. Tincani and G. Grioli and M. G. Catalano and M. Bonilla and M. Garabini and G Fantoni and A. Bicchi} } @conference {1438, title = {Implementation and Control of the Velvet Fingers: a Dexterous Gripper with Active Surfaces}, booktitle = {IEEE International Conference on Robotics and Automation (ICRA2013)}, year = {2013}, pages = {2744 - 2750}, keywords = {Haptics, Robotics}, url = {10.1109/ICRA.2013.6630955 }, author = {V. Tincani and G. Grioli and M. G. Catalano and M. Garabini and S. Grechi and G Fantoni and A. Bicchi} } @conference {1437, title = {Optimal Control and Design Guidelines for Soft Jumping Robots: Series Elastic Actuation and Parallel Elastic Actuation in comparison}, booktitle = {IEEE International Conference on Robotics and Automation (ICRA2013)}, year = {2013}, pages = {2477 - 2484}, keywords = {Robotics}, url = {10.1109/ICRA.2013.6630914 }, author = {R. Incaini and L. Sestini and M. Garabini and M. G. Catalano and G. Grioli and A. Bicchi} } @conference {1447, title = {Optimal Control for Maximizing Velocity of the CompActTM Compliant Actuator}, booktitle = {IEEE International Conference on Robotics and Automation (ICRA2013)}, year = {2013}, pages = {516 - 522}, keywords = {Robotics}, url = {10.1109/ICRA.2013.6630623}, author = {L. Chen and M. Garabini and M. Laffranchi and N. Kashiri and N G Tsagarakis and A. Bicchi and D. G. Caldwell} } @conference {1987, title = {Soft-Actuators in Cyclic Motion: Analytical Optimization of Stiffness and Pre-Load}, booktitle = {IEEE-RAS International Conference on Humanoid Robots}, year = {2013}, address = {Atlanta, Georgia, USA}, keywords = {Robotics}, author = {A. Velasco and G M Gasparri and M. Garabini and L. Malagia and P Salaris and A. Bicchi} } @article {1698, title = {Variable Impedance Actuators: a Review}, journal = {Robotics and Autonomous Systems}, volume = {61}, year = {2013}, note = {

Available online 6 August 2013

}, month = {12/2013}, pages = {1601{\textendash}1614}, abstract = {

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{\textquoteright}s to be guided in the design and implementation process for their targeted application.

}, keywords = {Robotics, Soft robotics, Variable Impedance Actuators}, url = {http://www.sciencedirect.com/science/article/pii/S0921889013001188}, author = {B. Vanderborght and A Albu-Schaeffer and A. Bicchi and E. Burdet and D. G. Caldwell and R. Carloni and M. G. Catalano and O. Eiberger and W. Friedl and G. Ganesh and M. Garabini and M. Grebenstein and G. Grioli and S. Haddadin and H. Hoppner and A. Jafari and M. Laffranchi and D. Lefeber and F. Petit and S. Stramigioli and N G Tsagarakis and M. Van Damme and R. Van Ham and L. C. Visser and S. Wolf} } @conference {GBSPB12, title = {Optimality Principles in Stiffness Control: The VSA Kick}, booktitle = {International Conference of Robotics and Automation - ICRA 2012}, year = {2012}, month = {May 14 - 18}, pages = {3341 - 3346 }, address = {Saint Paul, MN, USA}, keywords = {Robotics}, author = {M. Garabini and A. Passaglia and F. A. W. Belo and P Salaris and A. Bicchi} } @conference {MGCGBB12, title = {Passive impedance control of a Qboid multi-DOF VSA-CubeBot manipulator}, booktitle = {International Conference of Robotics and Automation - ICRA 2012}, year = {2012}, month = {May 14 - 18}, pages = {3335 - 3340 }, address = {Saint Paul, MN, USA}, keywords = {Robotics}, doi = {10.1109/ICRA.2012.6225082 }, author = {M. Mancini and G. Grioli and M. G. Catalano and M. Garabini and F. Bonomo and A. Bicchi} } @conference {1239, title = {Towards variable impedance assembly: the VSA peg-in-hole}, booktitle = {IEEE-RAS International Conference on Humanoid Robots}, year = {2012}, address = {Osaka, Japan}, keywords = {Robotics}, author = {L. Balletti and A. Rocchi and F. A. W. Belo and M. G. Catalano and M. Garabini and G. Grioli and A. Bicchi} } @conference {CGGBDBTB12, title = {A Variable Damping module for Variable Impedance Actuation}, booktitle = {International Conference of Robotics and Automation - ICRA 2012}, year = {2012}, month = {May 14 - 18}, pages = {2666 - 2672}, address = {Saint Paul, MN, USA}, keywords = {Robotics}, author = {M. G. Catalano and G. Grioli and M. Garabini and F. A. W. Belo and A. Di Basco and N G Tsagarakis and A. Bicchi} } @article {1245, title = {Variable Impedance Actuators: Moving the Robots of Tomorrow}, year = {2012}, keywords = {Robotics}, author = {B. Vanderborght and A Albu-Schaeffer and A. Bicchi and E. Burdet and D. G. Caldwell and R. Carloni and M. G. Catalano and G. Ganesh and M. Garabini and G. Grioli and S. Haddadin and A. Jafari and M. Laffranchi and D. Lefeber and F. Petit and S. Stramigioli and N G Tsagarakis and M. Van Damme and R. Van Ham and L. C. Visser and S. Wolf} } @conference {1243, title = { Velvet fingers: A dexterous gripper with active surfaces}, booktitle = {International Conference of Intelligent Robots and Systems - IROS 2012}, year = {2012}, month = {October 7 - 12}, pages = {1257 - 1263 }, address = {Vilamoura, Algarve, Portugal}, keywords = {Robotics}, author = {V. Tincani and M. G. Catalano and E. Farnioli and M. Garabini and G. Grioli and G Fantoni and A. Bicchi} } @conference {GPBSB11, title = {Optimality Principles in Variable Stiffness Control: the VSA Hammer}, booktitle = {2011 IEEE/RSJ International Conference on Intelligent RObots and Systems}, year = {2011}, month = {September 25 - 3}, pages = {3770 - 3775}, address = {S. Francisco, USA}, keywords = {Robotics}, author = {M. Garabini and A. Passaglia and F. A. W. Belo and P Salaris and A. Bicchi} } @conference {GCGSSBMBP11, title = {Variable stiffness actuators: muscles for the next generation of robots}, booktitle = {Automatica.it 2011}, year = {2011}, note = {

poster presentation

}, month = {September, 7 - 9}, address = {Pisa, Italy}, keywords = {Robotics}, author = {G. Grioli and M. G. Catalano and M. Garabini and F. Bonomo and A. Serio and P Salaris and F. A. W. Belo and M. Mancini and A. Bicchi and A. Passaglia} } @conference {CGGBB11, title = {VSA - CubeBot. A modular variable stiffness platform for multi degrees of freedom systems}, booktitle = {2011 IEEE International Conference on Robotics and Automation}, year = {2011}, month = {May 9 - 13}, pages = {5090 - 5095}, address = {Shangai, China}, keywords = {Robotics}, author = {M. G. Catalano and G. Grioli and M. Garabini and F. Bonomo and M. Mancini and N G Tsagarakis and A. Bicchi} }