@article {3446, title = {Humanoids at Work: The WALK-MAN Robot in a Postearthquake Scenario}, journal = {IEEE Robotics Automation Magazine}, year = {2018}, pages = {1-1}, keywords = {Buildings, Earthquakes, Hardware, Legged locomotion, Robot sensing systems, Task analysis}, issn = {1070-9932}, doi = {10.1109/MRA.2017.2788801}, author = {F. Negrello and A Settimi and D. Caporale and G. Lentini and M. Poggiani and D. Kanoulas and L. Muratore and Luberto, E. and G. Santaera and L. Ciarleglio and L. Ermini and L. Pallottino and D. G. Caldwell and N. Tsagarakis and A. Bicchi and M. Garabini and M. G. Catalano} } @inbook {3381, title = {WALK-MAN Humanoid Platform}, booktitle = {The DARPA Robotics Challenge Finals: Humanoid Robots To The Rescue}, volume = {121}, number = {The DARPA Robotics Challenge Finals: Humanoid Robots To The Rescue}, year = {2018}, pages = {495{\textendash}548}, publisher = {Springer}, organization = {Springer}, doi = {10.1007/978-3-319-74666-1_13}, author = {N. G. Tsagarakis and F. Negrello and M. Garabini and W. Choi and L. Baccelliere and V. G. Loc and J. Noorden and M. G. Catalano and M. Ferrati and L. Muratore and P. Kryczka and E. Mingo Hoffman and A Settimi and A. Rocchi and A. Margan and S. Cordasco and D. Kanoulas and A. Cardellino and L. Natale and H. Dallali and J. Malzahn and N. Kashiri and V. Varricchio and L. Pallottino and C. Pavan and J. Lee and A. Ajoudani and D. G. Caldwell 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} } @article {2841, title = {An Integrated Approach to Characterize the Behavior of a Human Fingertip in Contact with a Silica Window}, journal = {IEEE Transactions on Haptics}, volume = {10}, year = {2017}, month = {01/2017}, pages = {123-129}, abstract = {

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{\textquoteright}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.

}, keywords = {Haptics, Robotics}, issn = {1939-1412}, doi = { 10.1109/TOH.2016.2614679}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7579582}, author = {M. L. D{\textquoteright}Angelo and F. Cannella and M. Bianchi and M. D{\textquoteright}Imperio and E. Battaglia and M. Poggiani and G. Rossi and A. Bicchi and D. G. Caldwell} } @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} } @article {2904, title = {Variable Stiffness Actuators: Review on Design and Components}, journal = { IEEE/ASME Transactions on Mechatronics }, volume = {21}, year = {2016}, month = {10/2016}, pages = {2418 - 2430}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/TMECH.2015.2501019}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7330025}, author = {S. Wolf and G. Grioli and O. Eiberger and W. Friedl and M. Grebenstein and H. Hoppner and E. Burdet and D. G. Caldwell and R. Carloni and M. G. Catalano and D. Lefeber and S. Stramigioli and N. G. Tsagarakis and M. Van Damme and R. Van Ham and B. Vanderborght and L. C. Visser and A. Bicchi and A Albu-Schaeffer} } @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 {2454, title = {Characterization of Nonlinear Finger Pad Mechanics for Tactile Rendering}, booktitle = {IEEE World Haptics Conference}, year = {2015}, note = {

softhands, werahap

}, pages = {63-68}, address = {Chicago, USA, 22-25 June 2015}, abstract = {

The computation of skin forces and deformations for\ tactilerendering\ 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\ tactilerendering. 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.

}, keywords = {Haptics, Robotics}, doi = {10.1109/WHC.2015.7177692}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7177692}, author = {E. Miguel and M. L. D{\textquoteright}Angelo and F. Cannella and M. Bianchi and M Memeo and A. Bicchi and D. G. Caldwell and M. A. Otaduy} } @conference {2336, title = {Kinematic Analysis and Design Considerations for Optimal Base Frame Arrangement of Humanoid Shoulders}, booktitle = {IEEE International Conference on Robotics and Automation (ICRA2015)}, year = {2015}, pages = {2710 - 2715}, address = {Seattle, USA, 25 - 30 May}, keywords = {Robotics}, doi = {10.1109/ICRA.2015.7139566}, author = {M. Bagheri and A. Ajoudani and J. Lee and D. G. Caldwell and N G Tsagarakis} } @article {2158, title = {Tele- Impedance based Assistive Control for a Compliant Knee Exoskeleton: Stiffness Augmentation and Motion Assistance}, journal = {Robotics and Autonomous Systems}, volume = {73 part A}, year = {2015}, note = {

special issue\ "Wearable Robotics"

}, month = {11/2015}, pages = {78-90}, abstract = {

This paper presents a tele-impedance based assistive control scheme for a knee exoskeleton device. The proposed controller captures the user{\textquoteright}s intent to generate task-related assistive torques by means of the exoskeleton in different phases of the subject{\textquoteright}s normal activity. To do so, a detailed musculoskeletal model of the human knee is developed and experimentally calibrated to best match the user{\textquoteright}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{\textquoteright}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{\textendash}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{\textquoteright}s muscle activity.

}, keywords = {Robotics}, doi = {10.1016/j.robot.2014.09.027}, url = {http://www.sciencedirect.com/science/article/pii/S0921889014002127}, author = {N. Karavas and A. Ajoudani and N G Tsagarakis and J. Saglia and A. Bicchi and D. Caldwell} } @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} } @inbook {1694, title = {HANDS.DVI: A DeVice-Independent programming and control framework for robotic HANDS}, booktitle = {Gearing up and accelerating cross-fertilization between academic and industrial robotics research in Europe - Technology transfer experiments from the ECHORD project}, volume = {94}, number = {Springer Tracts in Advanced Robotics}, year = {2014}, pages = {197-215}, abstract = {

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.

}, keywords = {Haptics, Robotics}, doi = {10.1007/978-3-319-02934-4_10}, author = {G. Salvietti and G. Gioioso and M. Malvezzi and D Prattichizzo and A. Serio and E. Farnioli and M Gabiccini and A. Bicchi and I. Sarakoglou and N G Tsagarakis and D. G. Caldwell} } @conference {2119, title = {Haptic Exploration of Unknown Surfaces with Discontinuities}, booktitle = {Proc. IEEE/RSJ Intl Conf. on Intelligent Robots and Systems (IROS 2014)}, year = {2014}, month = {09/2014}, pages = {1255 - 1260}, address = {Chicago, USA}, keywords = {Haptics, Robotics}, doi = {10.1109/IROS.2014.6942718}, url = {http://kormushev.com/papers/Jamisola_IROS-2014.pdf}, author = {Jamisola, R. S. and Kormushev, P. and A. Bicchi and D. G. Caldwell} } @conference {2159, title = {Manipulation Framework for Compliant Humanoid COMAN: Application to a Valve Turning Task}, booktitle = {IEEE-RAS International Conference on Humanoid Robots (HUMANOIDS 2014)}, year = {2014}, pages = {664 - 670}, publisher = {IEEE}, organization = {IEEE}, address = {Madrid, Spain, November 18 - 20}, abstract = {

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{\textquoteright}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.

}, keywords = {Haptics, Robotics}, doi = {10.1109/HUMANOIDS.2014.7041434}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7041434}, author = {A. Ajoudani and J. Lee and A. Rocchi and M. Ferrati and E. Mingo Hoffman and A Settimi and D. G. Caldwell and A. Bicchi and N G Tsagarakis} } @conference {2160, title = {Upper-body Impedance Control with an Intuitive Stiffness Emulation for a Door Opening Task}, booktitle = {IEEE-RAS International Conference on Humanoid Robots (HUMANOIDS 2014)}, year = {2014}, pages = {713 - 719}, publisher = {IEEE}, organization = {IEEE}, address = {Madrid, Spain, November 18 - 20}, abstract = {

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.

}, keywords = {Robotics}, doi = {10.1109/HUMANOIDS.2014.7041441}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7041441}, author = {J. Lee and A. Ajoudani and E. Mingo Hoffman and A. Rocchi and A Settimi and M. Ferrati and A. Bicchi and N G Tsagarakis and D. G. Caldwell} } @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 {1435, title = {Tele-Impedance based Stiffness and Motion Augmentation for a Knee Exoskeleton Device}, booktitle = {IEEE International Conference on Robotics and Automation (ICRA2013)}, year = {2013}, pages = {2194 - 2200}, keywords = {Robotics}, url = {10.1109/ICRA.2013.6630872}, author = {N. Karavas and A. Ajoudani and N G Tsagarakis and J. Saglia and A. Bicchi and D. G. Caldwell} } @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} } @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} }