TY - JOUR T1 - A Configurable Architecture for Two Degree-of-Freedom Variable Stiffness Actuators to Match the Compliant Behavior of Human Joints JF - Frontiers in Robotics and AI Y1 - 2021 A1 - S. Lemerle A1 - M. G. Catalano A1 - A. Bicchi A1 - G. Grioli KW - articulated soft robotics KW - artificial joints KW - humanoids KW - prostheses KW - variable stiffness AB -

Living beings modulate the impedance of their joints to interact proficiently, robustly, and safely with the environment. These observations inspired the design of soft articulated robots with the development of Variable Impedance and Variable Stiffness Actuators. However, designing them remains a challenging task due to their mechanical complexity, encumbrance, and weight, but also due to the different specifications that the wide range of applications requires. For instance, as prostheses or parts of humanoid systems, there is currently a need for multi-degree-of-freedom joints that have abilities similar to those of human articulations. Toward this goal, we propose a new compact and configurable design for a two-degree-of-freedom variable stiffness joint that can match the passive behavior of a human wrist and ankle. Using only three motors, this joint can control its equilibrium orientation around two perpendicular axes and its overall stiffness as a one-dimensional parameter, like the co-contraction of human muscles. The kinematic architecture builds upon a state-of-the-art rigid parallel mechanism with the addition of nonlinear elastic elements to allow the control of the stiffness. The mechanical parameters of the proposed system can be optimized to match desired passive compliant behaviors and to fit various applications (e.g., prosthetic wrists or ankles, artificial wrists, etc.). After describing the joint structure, we detail the kinetostatic analysis to derive the compliant behavior as a function of the design parameters and to prove the variable stiffness ability of the system. Besides, we provide sets of design parameters to match the passive compliance of either a human wrist or ankle. Moreover, to show the versatility of the proposed joint architecture and as guidelines for the future designer, we describe the influence of the main design parameters on the system stiffness characteristic and show the potential of the design for more complex applications

VL - 8 UR - https://www.frontiersin.org/article/10.3389/frobt.2021.614145 ER - TY - JOUR T1 - Exploring Stiffness Modulation in Prosthetic Hands and Its Perceived Function in Manipulation and Social Interaction. JF - Frontiers in Neurorobotics Y1 - 2020 A1 - Capsi-Morales, Patricia A1 - C. Piazza A1 - M. G. Catalano A1 - A. Bicchi A1 - G. Grioli KW - human-robot social interaction KW - impedance control KW - prosthetics KW - Soft robotics KW - task adaptability AB -

To physically interact with a rich variety of environments and to match situation-dependent requirements, humans adapt both the force and stiffness of their limbs. Reflecting this behavior in prostheses may promote a more natural and intuitive control and, consequently, improve prostheses acceptance in everyday life. This pilot study proposes a method to control a prosthetic robot hand and its impedance, and explores the utility of variable stiffness when performing activities of daily living and physical social interactions. The proposed method is capable of a simultaneous and proportional decoding of position and stiffness intentions from two surface electro-myographic sensors placed over a pair of antagonistic muscles. The feasibility of our approach is validated and compared to existing control modalities in a preliminary study involving one prosthesis user. The algorithm is implemented in a soft under-actuated prosthetic hand (SoftHand Pro). Then, we evaluate the usability of the proposed approach while executing a variety of tasks. Among these tasks, the user interacts with other 12 able-bodied subjects, whose experiences were also assessed. Several statistically significant aspects from the System Usability Scale indicate user's preference of variable stiffness control over low or high constant stiffness due to its reactivity and adaptability. Feedback reported by able-bodied subjects reveal a general tendency to favor soft interaction, i.e., low stiffness, which is perceived more human-like and comfortable. These combined results suggest the use of variable stiffness as a viable compromise between firm control and safe interaction which is worth investigating further.

VL - 14 UR - https://www.frontiersin.org/articles/10.3389/fnbot.2020.00033/full?&utm_source=Email_to_authors_&utm_medium=Email&utm_content=T1_11.5e1_author&utm_campaign=Email_publication&field=&journalName=Frontiers_in_Neurorobotics&id=503842 IS - 33 JO - Exploring Stiffness Modulation in Prosthetic Hand ER - TY - JOUR T1 - Exploring the Role of Palm Concavity and Adaptability in Soft Synergistic Robotic Hands JF - IEEE Robotics and Automation Letters Y1 - 2020 A1 - Capsi-Morales, Patricia A1 - G. Grioli A1 - C. Piazza A1 - A. Bicchi A1 - M. G. Catalano KW - Ellipsoids KW - Grasping KW - Indexes KW - Kinematics KW - Robots KW - Shape KW - Thumb AB -

Robotic hand engineers usually focus on finger capabilities, often disregarding the palm contribution. Inspired by human anatomy, this paper explores the advantages of including a flexible concave palm into the design of a robotic hand actuated by soft synergies. We analyse how the inclusion of an articulated palm improves finger workspace and manipulability. We propose a mechanical design of a modular palm with two elastic rolling-contact palmar joints, that can be integrated on the Pisa/IIT SoftHand, without introducing additional motors. With this prototype, we evaluate experimentally the grasping capabilities of a robotic palm. We compare its performance to that of the same robotic hand with the palm fixed, and to that of a human hand. To assess the effective grasp quality achieved by the three systems, we measure the contact area using paint-transfer patterns in different grasping actions. Preliminary grasping experiments show a closer resemblance of the soft-palm robotic hand to the human hand. Results evidence a higher adaptive capability and a larger involvement of all fingers in grasping.

VL - 5 UR - https://ieeexplore.ieee.org/document/9119822?source=authoralert IS - 3 ER - TY - Generic T1 - SIMULTANEOUS AND PROPORTIONAL DECODING OF STIFFNESS AND POSITION INTENTIONS FROM TWO SEMG CHANNELS FOR UL PROSTHETICS T2 - MEC20 Symposium Y1 - 2020 A1 - Capsi-Morales, Patricia A1 - C. Piazza A1 - M. G. Catalano A1 - A. Bicchi A1 - G. Grioli AB -

To physically interact with a rich variety of environments and situation-oriented requirements, humans continuously adapt both the stiffness and the force of their limbs through antagonistic muscle coactivation. Reflecting this behaviour in prostheses may promote control naturalness and intuitiveness and, consequently, their acceptance in everyday life. We propose a method capable of a simultaneous and proportional decoding of position and stiffness intentions from two surface electro-myographic sensors placed over a pair of antagonistic muscles. First, the algorithm is validated and compared to existing control modalities. Then, the algorithm is implemented in a soft under-actuated prosthetic hand (SoftHand Pro). We investigated the feasibility of our approach in a preliminary study involving one prosthetic user. Our future goal is to evaluate the usability of the proposed approach executing a variety of tasks including physical social interaction with other subjects (see Figure 1). Our hypothesis is that variable stiffness could be a compromise between firm control and safe interaction.

JF - MEC20 Symposium UR - https://conferences.lib.unb.ca/index.php/mec/article/view/35 ER - TY - PAT T1 - Artificial hand Y1 - 2019 A1 - A. Bicchi A1 - M. G. Catalano A1 - C. Piazza A1 - G. Grioli A1 - C. Della Santina A1 - M. Garabini UR - https://patentimages.storage.googleapis.com/4f/2c/07/915e9723cfe164/US20190269528A1.pdf ER - TY - JOUR T1 - A Century of Robotic Hands JF - Annual Review of Control, Robotics, and Autonomous Systems Y1 - 2019 A1 - C. Piazza A1 - G. Grioli A1 - M. G. Catalano A1 - A. Bicchi VL - 2 UR - https://www.annualreviews.org/doi/10.1146/annurev-control-060117-105003 ER - TY - JOUR T1 - Design and Assessment of Control Maps for Multi-Channel sEMG-Driven Prostheses and Supernumerary Limbs JF - Frontiers in neurorobotics Y1 - 2019 A1 - M. Maimeri A1 - C. Della Santina A1 - C. Piazza A1 - M. Rossi A1 - M. G. Catalano A1 - G. Grioli VL - 13 ER - TY - JOUR T1 - Design and Assessment of Control Maps for Multi-Channel sEMG-Driven Prostheses and Supernumerary Limbs JF - Frontiers in neurorobotics Y1 - 2019 A1 - M. Maimeri A1 - C. Della Santina A1 - C. Piazza A1 - M. Rossi A1 - M. G. Catalano A1 - G. Grioli VL - 13 UR - https://www.frontiersin.org/articles/10.3389/fnbot.2019.00026/full ER - TY - JOUR T1 - Dynamic Morphological Computation Through Damping Design of Soft Continuum Robots JF - Frontiers in Robotics and AI Y1 - 2019 A1 - A. Di Lallo A1 - M. G. Catalano A1 - M. Garabini A1 - G. Grioli A1 - M Gabiccini A1 - A. Bicchi ER - TY - JOUR T1 - Exploiting Adaptability in Soft Feet for Sensing Contact Forces JF - IEEE Robotics and Automation Letters Y1 - 2019 A1 - D. Mura A1 - C. Della Santina A1 - C. Piazza A1 - I. Frizza A1 - C. Morandi A1 - M. Garabini A1 - G. Grioli A1 - M. G. Catalano VL - 5 UR - https://ieeexplore.ieee.org/document/8894422 IS - 2 ER - TY - JOUR T1 - A Novel Skin-Stretch Haptic Device for Intuitive Control of Robotic Prostheses and Avatars JF - IEEE Robotics and Automation Letters Y1 - 2019 A1 - N. Colella A1 - M. Bianchi A1 - G. Grioli A1 - A. Bicchi A1 - M. G. Catalano VL - Volume: 4 , Issue: 2 , April 2019 ER - TY - JOUR T1 - Relaying the High-Frequency Contents of TactileFeedback to Robotic Prosthesis Users: Design,Filtering, Implementation, and Validation JF - IEEE Robotics and Automation Letters Y1 - 2019 A1 - S. Fani A1 - K. Di Blasio A1 - M. Bianchi A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi VL - Volume: 4 , Issue: 2 , April 2019 ER - TY - JOUR T1 - A Spherical Active Joint for Humanoids and Humans JF - IEEE Robotics and Automation Letters Y1 - 2019 A1 - S. Mghames A1 - M. G. Catalano A1 - A. Bicchi A1 - G. Grioli VL - Volume: 4 , Issue: 2 , April 2019 ER - TY - CONF T1 - Advanced grasping with the Pisa/IIT softHand T2 - Robotic Grasping and Manipulation Challenge Y1 - 2018 A1 - M. Bonilla A1 - C. Della Santina A1 - A. Rocchi A1 - E. Luberto A1 - G. Santaera A1 - E. Farnioli A1 - C. Piazza A1 - F. Bonomo A1 - A. Brando A1 - A. Raugi A1 - M. G. Catalano A1 - M. Bianchi A1 - M. Garabini A1 - G. Grioli A1 - A. Bicchi JF - Robotic Grasping and Manipulation Challenge ER - TY - JOUR T1 - Decentralized Trajectory Tracking Control for Soft Robots Interacting with the Environment JF - IEEE Transactions on Robotics (T-RO). Y1 - 2018 A1 - F. Angelini A1 - C. Della Santina A1 - M. Garabini A1 - M. Bianchi A1 - G M Gasparri A1 - G. Grioli A1 - M. G. Catalano A1 - A. Bicchi KW - Robotics AB -

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.

VL - Early Access ER - TY - JOUR T1 - Efficient Walking Gait Generation via Principal Component Representation of Optimal Trajectories: Application to a Planar Biped Robot With Elastic Joints JF - IEEE Robotics and Automation Letters Y1 - 2018 A1 - G M Gasparri A1 - S. Manara A1 - D. Caporale A1 - G. Averta A1 - M. Bonilla A1 - H. Marino A1 - M. G. Catalano A1 - G. Grioli A1 - M. Bianchi A1 - A. Bicchi A1 - M. Garabini AB -

Recently, the method of choice to exploit robot dynamics for efficient walking is numerical optimization (NO). The main drawback in NO is the computational complexity, which strongly affects the time demand of the solution. Several strategies can be used to make the optimization more treatable and to efficiently describe the solution set. In this letter, we present an algorithm to encode effective walking references, generated offline via numerical optimization, extracting a limited number of principal components and using them as a basis of optimal motions. By combining these components, a good approximation of the optimal gaits can be generated at run time. The advantages of the presented approach are discussed, and an extensive experimental validation is carried out on a planar legged robot with elastic joints. The biped thus controlled is able to start and stop walking on a treadmill, and to control its speed dynamically as the treadmill speed changes.

VL - 3 ER - TY - CONF T1 - ExoSense: Measuring Manipulation in a Wearable Manner T2 - Proceedings - IEEE International Conference on Robotics and Automation Y1 - 2018 A1 - E. Battaglia A1 - M. G. Catalano A1 - G. Grioli A1 - M. Bianchi A1 - A. Bicchi JF - Proceedings - IEEE International Conference on Robotics and Automation ER - TY - CONF T1 - A Novel Approach to Under-Actuated Control of Fluidic Systems T2 - 2018 IEEE International Conference on Robotics and Automation (ICRA) Y1 - 2018 A1 - A. Di Lallo A1 - M. G. Catalano A1 - M. Garabini A1 - G. Grioli A1 - M. Gabiccini A1 - A. Bicchi JF - 2018 IEEE International Conference on Robotics and Automation (ICRA) UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8460859&isnumber=8460178 ER - TY - JOUR T1 - Simplifying Telerobotics: Wearability and Teleimpedance Improves Human-Robot Interactions in Teleoperation JF - IEEE Robotics Automation Magazine Y1 - 2018 A1 - S. Fani A1 - S. Ciotti A1 - M. G. Catalano A1 - G. Grioli A1 - A. Tognetti A1 - G. Valenza A1 - A. Ajoudani A1 - M. Bianchi KW - application fields KW - augmented teleoperation KW - Autonomous robots KW - communication KW - effective design KW - effective simplification KW - environmental constraints KW - feedback KW - Force feedback KW - fundamental requirement KW - haptic feedback devices KW - haptic interfaces KW - human workspace KW - human-robot interaction KW - human-robot interactions KW - human-robot interfaces KW - ideal scenario KW - integrated approach KW - integrated interface KW - integrated system KW - interaction forces KW - intuitive information exchange KW - Kinematics KW - KUKA lightweight robotic arm KW - lightweight design KW - manipulators KW - master KW - position control KW - reduced versions KW - Robot sensing systems KW - robotic devices KW - robotic hand-arm system KW - robotic manipulator KW - robotic teleoperation KW - simplified information exchange KW - slave robot KW - stiffness control KW - synergy KW - Task analysis KW - teleimpedance techniques KW - Telemedicine KW - teleoperator system KW - telerobotics KW - TI control KW - vision KW - wearability KW - wearable feedback KW - wearable hand/arm VL - 25 ER - TY - JOUR T1 - The SoftHand Pro: Functional evaluation of a novel, flexible, and robust myoelectric prosthesis JF - PLOS One Y1 - 2018 A1 - S. B. Godfrey A1 - K. Zhao A1 - A. Theuer A1 - M. G. Catalano A1 - M. Bianchi A1 - R. Breighner A1 - D. Bhaskaran A1 - R. Lennon A1 - G. Grioli A1 - M. Santello A1 - A. Bicchi A1 - K. Andrews ER - TY - JOUR T1 - Towards Dexterous Manipulation with Augmented Adaptive Synergies: the Pisa/IIT SoftHand 2 JF - IEEE Transactions on Robotics Y1 - 2018 A1 - C. Della Santina A1 - C. Piazza A1 - G. Grioli A1 - M. G. Catalano A1 - A. Bicchi AB -

In the recent years, a clear trend towards simplification emerged in the development of robotic hands. The use of soft robotic approaches has been a useful tool in this prospective, enabling complexity reduction by embodying part of grasping intelligence in the hand mechanical structure. Several hand prototypes designed according to such principles have accomplished good results in terms of grasping simplicity, robustness, and reliability. Among them, the Pisa/IIT SoftHand demonstrated the feasibility of a large variety of grasping tasks, by means of only one actuator and an opportunely designed tendon driven differential mechanism. However, the use of a single degree of actuation prevents the execution of more complex tasks, like fine pre-shaping of fingers and in-hand manipulation. While possible in theory, simply doubling the Pisa/IIT SoftHand actuation system has several disadvantages, e.g. in terms of space and mechanical complexity. To overcome these limitations we propose a novel design framework for tendon driven mechanisms, where the main idea is to turn transmission friction from a disturbance into a design tool. In this way the degrees of actuation can be doubled with little additional complexity.

By leveraging on this idea we design a novel robotic hand, the Pisa/IIT SoftHand 2. We present here its design, modeling, control, and experimental validation. The hand demonstrates that by opportunely combining only two degrees of actuation with hand softness, a large variety of grasping and manipulation tasks can be performed only relying on the intelligence embodied in the mechanism. Examples include rotating objects with different shapes, opening a jar, pouring coffee from a glass.

VL - Early Access ER - TY - PAT T1 - Underactuated robotic hand Y1 - 2018 A1 - A. Bicchi A1 - C. Della Santina A1 - M. G. Catalano A1 - C. Piazza A1 - G. Grioli A1 - A. Brando UR - https://patentimages.storage.googleapis.com/c3/76/f4/3f31e20b15ad53/US20180311827A1.pdf ER - TY - JOUR T1 - Controlling Soft Robots: Balancing Feedback and Feedforward Elements JF - IEEE Robotics and Automation Magazine Y1 - 2017 A1 - C. Della Santina A1 - M. Bianchi A1 - G. Grioli A1 - F. Angelini A1 - M. G. Catalano A1 - M. Garabini A1 - A. Bicchi KW - Robotics AB -

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.

VL - 24 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7930438 IS - 3 N1 -

This work is supported by European Commission grant H2020-ICT-645599 (“SOMA”: SOft Manipulation) and European Research Council Advanced grant 291166 (“SoftHands”).

ER - TY - CONF T1 - Design, control and validation of the variable stiffness exoskeleton FLExo T2 - International Conference on Rehabilitation Robotics (ICORR) Y1 - 2017 A1 - S. Mghames A1 - M. Laghi A1 - C. Della Santina A1 - M. Garabini A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Robotics AB -

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.

JF - International Conference on Rehabilitation Robotics (ICORR) PB - IEEE CY - London, UK, 17-20 July 2017 UR - http://ieeexplore.ieee.org/document/8009304/ ER - TY - CONF T1 - Design of an Under-Actuated Wrist Based on Adaptive Synergies T2 - IEEE International Conference of Robotics and Automation, ICRA2017 Y1 - 2017 A1 - S. Casini A1 - V. Tincani A1 - G. Averta A1 - M. Poggiani A1 - C. Della Santina A1 - E. Battaglia A1 - M. G. Catalano A1 - M. Bianchi A1 - G. Grioli A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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.

JF - IEEE International Conference of Robotics and Automation, ICRA2017 PB - IEEE CY - Singapore, 29 May-3 June 2017 UR - http://ieeexplore.ieee.org/document/7989789/ ER - TY - CONF T1 - Design of an under-actuated wrist based on adaptive synergies T2 - Robotics and Automation (ICRA), 2017 IEEE International Conference on Y1 - 2017 A1 - S. Casini A1 - V. Tincani A1 - G. Averta A1 - M. Poggiani A1 - C. Della Santina A1 - E. Battaglia A1 - M. G. Catalano A1 - M. Bianchi A1 - G. Grioli A1 - A. Bicchi AB -

An effective robotic wrist represents a key en- abling 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 intro- duce 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.

JF - Robotics and Automation (ICRA), 2017 IEEE International Conference on PB - IEEE ER - TY - CONF T1 - Estimating Contact Forces from Postural Measures in a class of Under-Actuated Robotic Hands T2 - IEEE International Conference of Intelligent Robots and Systems (IROS2017) Y1 - 2017 A1 - C. Della Santina A1 - C. Piazza A1 - G. Santaera A1 - G. Grioli A1 - M. G. Catalano A1 - A. Bicchi KW - Robotics JF - IEEE International Conference of Intelligent Robots and Systems (IROS2017) PB - IEEE CY - Vancouver, Canada, September 24–28, 2017 ER - TY - CONF T1 - Preliminary results toward a naturally controlled multi-synergistic prosthetic hand T2 - International Conference on Rehabilitation Robotics (ICORR) Y1 - 2017 A1 - M. Rossi A1 - C. Della Santina A1 - C. Piazza A1 - G. Grioli A1 - M. G. Catalano A1 - A. Bicchi KW - Robotics AB -

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.

JF - International Conference on Rehabilitation Robotics (ICORR) SN - 978-1-5386-2296-4 UR - http://ieeexplore.ieee.org/abstract/document/8009437/ ER - TY - JOUR T1 - The Quest for Natural Machine Motion: An Open Platform to Fast-Prototyping Articulated Soft Robots JF - IEEE Robotics and Automation Magazine Y1 - 2017 A1 - C. Della Santina A1 - C. Piazza A1 - Gasparri, G. M. A1 - M. Bonilla A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - A. Bicchi KW - Robotics AB -
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.
VL - 24 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7857692 IS - 1 N1 -

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)—projects of the European Commission’s Horizon
2020 research program—and by Walk-Man grant 611832.
Support also came from the European Research Council
under an Advanced Grant for “SoftHands: A Theory of Soft
Synergies for a New Generation of Artificial Hands” (grant
ERC-291166).
ER - TY - JOUR T1 - SoftHand at the CYBATHLON: A user's experience JF - JOURNAL OF NEUROENGINEERING AND REHABILITATION Y1 - 2017 A1 - S. B. Godfrey A1 - M. Rossi A1 - C. Piazza A1 - M. G. Catalano A1 - M. Bianchi A1 - G. Grioli A1 - K. Zhao A1 - A. Bicchi ER - TY - JOUR T1 - The SoftHand Pro-H: A Hybrid Body-Controlled, Electrically Powered Hand Prosthesis for Daily Living and Working JF - IEEE Robotics and Automation Magazine Y1 - 2017 A1 - C. Piazza A1 - M. G. Catalano A1 - S. B. Godfrey A1 - M. Rossi A1 - G. Grioli A1 - M. Bianchi A1 - K. Zhao A1 - A. Bicchi KW - Haptics KW - Robotics UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8110634 N1 -

This work was supported by the European Commission project (Horizon 2020 research program) SOFTPRO 688857, the European Research Council under the Advanced Grant SoftHands “A Theory of Soft Synergies for a New Generation of Artificial Hands,” ERC-291166, and the Proof of Concept Project SoftHand Pro-H, ERC-2016-PoC 727536. 

ER - TY - JOUR T1 - Assessment of Myoelectric Controller Performance and Kinematic Behavior of a Novel Soft Synergy-inspired Robotic Hand for Prosthetic Applications JF - Frontiers in Neurorobotics Y1 - 2016 A1 - S. Fani A1 - M. Bianchi A1 - S. Jain A1 - J. Pimenta Neto A1 - S. Boege A1 - G. Grioli A1 - A. Bicchi A1 - M. Santello KW - Haptics KW - Robotics AB -

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.

VL - 10 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5066092/ IS - 11 ER - TY - CHAP T1 - From Soft to Adaptive Synergies: The Pisa/IIT SoftHand T2 - Human and Robot Hands Y1 - 2016 A1 - M. G. Catalano A1 - G. Grioli A1 - E. Farnioli A1 - A. Serio A1 - M. Bonilla A1 - M. Garabini A1 - C. Piazza A1 - M Gabiccini A1 - A. Bicchi AB -

Taking inspiration from the neuroscientific findings on hand synergies discussed in the first part of the book, in this chapter we present the Pisa/IIT SoftHand, a novel robot hand prototype. The design moves under the guidelines of making an hardware robust and easy to control, preserving an high level of grasping capabilities and an aspect as similar as possible to the human counterpart. First, the main theoretical tools used to enable such simplification are presented, as for example the notion of soft synergies. A discussion of some possible actuation schemes shows that a straightforward implementation of the soft synergy idea in an effective design is not trivial. The proposed approach, called adaptive synergy, rests on ideas coming from underactuated hand design, offering a design method to implement the desired set of soft synergies as demonstrated both with simulations and experiments. As a particular instance of application of the synthesis method of adaptive synergies, the Pisa/IIT SoftHand is described in detail. The hand has 19 joints, but only uses one actuator to activate its adaptive synergy. Of particular relevance in its design is the very soft and safe, yet powerful and extremely robust structure, obtained through the use of innovative articulations and ligaments replacing conventional joint design. Moreover, in this work, summarizing results presented in previous papers, a discussion is presented about how a new set of possibilities is open from paradigm shift in manipulation approaches, moving from manipulation with rigid to soft hands.

JF - Human and Robot Hands PB - Springer VL - Springer Series on Touch and Haptic Systems ER - TY - CONF T1 - Natural encoding of user intentions in a soft prosthesis using Dynamic Synergies T2 - International Workshop on Human-Friendly Robotics Y1 - 2016 A1 - C. Piazza A1 - C. Della Santina A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - A. Bicchi JF - International Workshop on Human-Friendly Robotics ER - TY - CONF T1 - Robust Optimization of System Compliance for Physical Interaction in Uncertain Scenarios T2 - IEEE International Conference on Humanoid Robots (HUMANOIDS2016) Y1 - 2016 A1 - Gasparri, G. M. A1 - F. Fabiani A1 - M. Garabini A1 - L. Pallottino A1 - M. G. Catalano A1 - G. Grioli A1 - R. Persichini A1 - A. Bicchi KW - Robotics AB -

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.

JF - IEEE International Conference on Humanoid Robots (HUMANOIDS2016) PB - IEEE CY - Cancun, Mexico, 15-17 Nov. 2016 SN - 978-1-5090-4718-5 UR - http://ieeexplore.ieee.org/document/7803381/ N1 -
This work was supported by the European Commission projects (FP7 framework) Walk-Man and the European Commission Grant no. H2020- ICT-645599 “SOMA”: SOft MAnipulation
ER - TY - CONF T1 - Soft Robots that Mimic the Neuromusculoskeletal System T2 - 3rd International Conference on NeuroRehabilitation (ICNR2016) Y1 - 2016 A1 - M. Garabini A1 - C. Della Santina A1 - M. Bianchi A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Robotics AB -

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.

JF - 3rd International Conference on NeuroRehabilitation (ICNR2016) PB - Springer VL - Converging Clinical and Engineering Research on Neurorehabilitation UR - http://link.springer.com/chapter/10.1007/978-3-319-46669-9_45 ER - TY - CHAP T1 - The SoftHand Pro: Translation from Robotic Hand to Prosthetic Prototype T2 - Converging Clinical and Engineering Research on Neurorehabilitation II Y1 - 2016 A1 - S. B. Godfrey A1 - M. Bianchi A1 - K. Zhao A1 - M. G. Catalano A1 - R. Breighner A1 - A. Theuer A1 - K. Andrews A1 - G. Grioli A1 - M. Santello A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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.

JF - Converging Clinical and Engineering Research on Neurorehabilitation II PB - Springer International Publishing VL - 15 UR - http://link.springer.com/chapter/10.1007/978-3-319-46669-9_78 N1 -

Proceedings of the 3rd International Conference on NeuroRehabilitation (ICNR2016), October 18-21, 2016, Segovia, Spain

ER - TY - CONF T1 - SoftHand Pro-D: Matching Dynamic Content of Natural User Commands with Hand Embodiment for Enhanced Prosthesis Control T2 - IEEE International Conference of Robotics and Automation (ICRA2016) Y1 - 2016 A1 - C. Piazza A1 - C. Della Santina A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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

JF - IEEE International Conference of Robotics and Automation (ICRA2016) PB - IEEE CY - Stockholm, Sweden, May 16-21 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7487532 N1 -

softpro soma softhands

ER - TY - JOUR T1 - ThimbleSense: a fingertip-wearable tactile sensor for grasp analysis JF - IEEE Transactions on Haptics Y1 - 2016 A1 - E. Battaglia A1 - M. Bianchi A1 - Altobelli, A A1 - G. Grioli A1 - M. G. Catalano A1 - A. Serio A1 - M. Santello A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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.

VL - 9 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7294702 IS - 1 N1 -
This work was partially supported by the European Community funded projects WEARHAP, PACMAN and SOMA (contracts 601165, 600918 and 645599 respectively), by the ERC Advanced Grant no. 291166 SoftHands
ER - TY - CONF T1 - Toward an Adaptive Foot for Natural Walking T2 - International Conference on Humanoid Robots (HUMANOIDS2016) Y1 - 2016 A1 - C. Piazza A1 - C. Della Santina A1 - Gasparri, G. M. A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - A. Bicchi KW - Robotics AB -

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.

JF - International Conference on Humanoid Robots (HUMANOIDS2016) CY - Cancun, Mexico, November 15-17, 2016 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7803423 ER - TY - JOUR T1 - Variable Stiffness Actuators: Review on Design and Components JF - IEEE/ASME Transactions on Mechatronics Y1 - 2016 A1 - S. Wolf A1 - G. Grioli A1 - O. Eiberger A1 - W. Friedl A1 - M. Grebenstein A1 - H. Hoppner A1 - E. Burdet A1 - D. G. Caldwell A1 - R. Carloni A1 - M. G. Catalano A1 - D. Lefeber A1 - S. Stramigioli A1 - N. G. Tsagarakis A1 - M. Van Damme A1 - R. Van Ham A1 - B. Vanderborght A1 - L. C. Visser A1 - A. Bicchi A1 - A Albu-Schaeffer KW - Robotics AB -

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.

VL - 21 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7330025 IS - 5 ER - TY - CONF T1 - Design and Realization of the CUFF - Clenching Upper-Limb Force Feedback Wearable Device for Distributed Mechano-Tactile Stimulation of Normal and Tangential Skin Forces T2 - IEEE International Conference of Intelligent Robots and Systems - IROS2015 Y1 - 2015 A1 - S. Casini A1 - M. Morvidoni A1 - M. Bianchi A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Robotics AB -

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.

JF - IEEE International Conference of Intelligent Robots and Systems - IROS2015 PB - IEEE CY - Hamburg, Germany, 28 Sept - 2 Oct 2015 UR - http://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%20Stimulatio N1 -

The authors want to thank Cosimo della Santina, Andrea Di Basco, Riccardo Persichini and Fabio Bonomo for their really valuable support in the development of the hardware prototype. This work is supported in part by the European Research Council under the Advanced Grant SoftHands “A Theory of Soft Synergies for a New Generation of Artificial Hands” (no. ERC-291166), and by the EU FP7 project (no. 601165) “WEARable HAPtics for Humans and Robots (WEARHAP)

ER - TY - CONF T1 - Dexterity augmentation on a synergistic hand: the Pisa/IIT SoftHand+ T2 - 15th IEEE RAS Humanoids Conference (HUMANOIDS2015) Y1 - 2015 A1 - C. Della Santina A1 - G. Grioli A1 - M. G. Catalano A1 - Brando, A. A1 - A. Bicchi KW - Haptics KW - Robotics AB -
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.
JF - 15th IEEE RAS Humanoids Conference (HUMANOIDS2015) PB - IEEE CY - Seoul, Korea, November 3 - 5, 2015 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7363595 N1 -

Softhands, SOMA

Best Interactive Paper Award

U1 -
This work is supported by the European Commission Grant no. H2020-ICT-645599 “SOMA”: SOft MAnipulation and the ERC Advanced Grant
no. 291166 “SoftHands”
ER - TY - CONF T1 - Potential merits for space robotics from novel concepts of actuation for soft robotics T2 - Advanced Space Technologies for Robotics and Automation (ASTRA) Y1 - 2015 A1 - G. Mathijssen A1 - S. Terryn A1 - R. Funemont A1 - M. Garabini A1 - M. G. Catalano A1 - G. Grioli A1 - D. Lefeber A1 - A. Bicchi A1 - B. Vanderborght KW - Robotics JF - Advanced Space Technologies for Robotics and Automation (ASTRA) CY - Noordwijk, The Netherlands May 11-13, 2015 ER - TY - JOUR T1 - Variable Stiffness Actuators: the user’s point of view JF - Int. J. Robotics Research Y1 - 2015 A1 - G. Grioli A1 - S. Wolf A1 - M. Garabini A1 - M. G. Catalano A1 - E. Burdet A1 - D. G. Caldwell A1 - R. Carloni A1 - W. Friedl A1 - M. Grebenstein A1 - M. Laffranchi A1 - D. Lefeber A1 - S. Stramigioli A1 - N G Tsagarakis A1 - M. Van Damme A1 - B. Vanderborght A1 - A Albu-Schaeffer A1 - A. Bicchi KW - Robotics VL - 34 UR - http://ijr.sagepub.com/cgi/reprint/0278364914566515v1.pdf?ijkey=anmgudvoLz7ZloP&keytype=finite IS - 6 N1 -

Extensions.zip

ER - TY - CONF T1 - Variable Stiffness Control for Oscillation Damping T2 - IEEE International Conference of Intelligent Robots and Systems (IROS2015) Y1 - 2015 A1 - G M Gasparri A1 - M. Garabini A1 - L. Pallottino A1 - L. Malagia A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - IEEE International Conference of Intelligent Robots and Systems (IROS2015) PB - IEEE CY - Hamburg, Germany, September 28 - October 02, 2015 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7354312 N1 -
This work is supported by the EC under the grant agreements no.611832 Walk-Man and ICT-287513 “SAPHARI”
ER - TY - JOUR T1 - Adaptive Synergies for the Design and Control of the Pisa/IIT SoftHand JF - International Journal of Robotics Research Y1 - 2014 A1 - M. G. Catalano A1 - G. Grioli A1 - E. Farnioli A1 - A. Serio A1 - C. Piazza A1 - A. Bicchi KW - Haptics KW - Robotics VL - 33 IS - 5 ER - TY - CONF T1 - Exploring haptic feedback for the Pisa/IIT SoftHand T2 - Haptics Symposium (HAPTICS), 2014 IEEE Y1 - 2014 A1 - S. B. Godfrey A1 - A. Ajoudani A1 - M. Bianchi A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Haptics KW - Robotics JF - Haptics Symposium (HAPTICS), 2014 IEEE CY - Houston, TX ER - TY - JOUR T1 - Exploring Teleimpedance and Tactile Feedback for Intuitive Control of the Pisa/IIT SoftHand JF - IEEE Transactions on Haptics Y1 - 2014 A1 - A. Ajoudani A1 - S. B. Godfrey A1 - M. G. Catalano A1 - M. Bianchi A1 - G. Grioli A1 - N G Tsagarakis A1 - A. Bicchi KW - Haptics KW - Robotics VL - 7 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6755554 IS - 2 ER - TY - CONF T1 - Grasping with Soft Hands T2 - IEEE-RAS International Conference on Humanoid Robots (HUMANOIDS 2014) Y1 - 2014 A1 - M. Bonilla A1 - E. Farnioli A1 - C. Piazza A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - M Gabiccini A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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.

JF - IEEE-RAS International Conference on Humanoid Robots (HUMANOIDS 2014) CY - Madrid, Spain, November 18 - 20 UR - http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=7041421&queryText%3DGrasping+with+Soft+Hands ER - TY - CONF T1 - Open Source VSA-CubeBots for Rapid Soft Robot Prototyping T2 - Robot Makers - Workshop in conjunction with 2014 Robotics Science and Systems Y1 - 2014 A1 - K. Melo A1 - M. Garabini A1 - G. Grioli A1 - M. G. Catalano A1 - L. Malagia A1 - A. Bicchi KW - Robotics JF - Robot Makers - Workshop in conjunction with 2014 Robotics Science and Systems CY - July 12, 2014, Berkeley, California ER - TY - JOUR T1 - A Stiffness Estimator for Agonistic–Antagonistic Variable-Stiffness-Actuator Devices JF - IEEE Transactions on Robotics Y1 - 2014 A1 - T. Menard A1 - G. Grioli A1 - A. Bicchi KW - Robotics AB -

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.

VL - 30 UR - http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6860244&queryText%3DA+stiffness+estimator+for+AA-VSA+devices IS - 5 ER - TY - CONF T1 - ThimbleSense: A new wearable tactile device for human and robotic fingers T2 - Haptics Symposium (HAPTICS), 2014 IEEE Y1 - 2014 A1 - E. Battaglia A1 - G. Grioli A1 - M. G. Catalano A1 - M. Bianchi A1 - A. Serio A1 - M. Santello A1 - A. Bicchi KW - Haptics KW - Robotics JF - Haptics Symposium (HAPTICS), 2014 IEEE CY - Houston, TX ER - TY - CONF T1 - ThimbleSense: An Individual-Digit Wearable Tactile Sensor for Experimental Grasp Studies T2 - IEEE International Conference on Robotics and Automation - ICRA 2014 Y1 - 2014 A1 - E. Battaglia A1 - G. Grioli A1 - M. G. Catalano A1 - M. Santello A1 - A. Bicchi KW - Haptics KW - Robotics AB -

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.

JF - IEEE International Conference on Robotics and Automation - ICRA 2014 PB - IEEE CY - Hong Kong, May 31 - June 7, 2014 UR - http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6907250 ER - TY - CONF T1 - Controlling the active surfaces of the Velvet Fingers: sticky to slippy fingers T2 - IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2013 Y1 - 2013 A1 - V. Tincani A1 - G. Grioli A1 - M. G. Catalano A1 - M. Bonilla A1 - M. Garabini A1 - G Fantoni A1 - A. Bicchi KW - Robotics AB -

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.

JF - IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2013 CY - Tokyo, Japan UR - http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6697152&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6697152 ER - TY - CONF T1 - Implementation and Control of the Velvet Fingers: a Dexterous Gripper with Active Surfaces T2 - IEEE International Conference on Robotics and Automation (ICRA2013) Y1 - 2013 A1 - V. Tincani A1 - G. Grioli A1 - M. G. Catalano A1 - M. Garabini A1 - S. Grechi A1 - G Fantoni A1 - A. Bicchi KW - Haptics KW - Robotics JF - IEEE International Conference on Robotics and Automation (ICRA2013) UR - 10.1109/ICRA.2013.6630955 ER - TY - CONF T1 - Optimal Control and Design Guidelines for Soft Jumping Robots: Series Elastic Actuation and Parallel Elastic Actuation in comparison T2 - IEEE International Conference on Robotics and Automation (ICRA2013) Y1 - 2013 A1 - R. Incaini A1 - L. Sestini A1 - M. Garabini A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - IEEE International Conference on Robotics and Automation (ICRA2013) UR - 10.1109/ICRA.2013.6630914 ER - TY - CONF T1 - A real time robust observer for an agonist antagonist variable stiffness actuator T2 - IEEE International Conference on Robotics and Automation (ICRA2013) Y1 - 2013 A1 - T. Menard A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - IEEE International Conference on Robotics and Automation (ICRA2013) CY - Karlsruhe, Germany, May 6-10, 2013 UR - 10.1109/ICRA.2013.6631139 N1 -

Best Paper Award Finalist

ER - TY - CONF T1 - A synergy-driven approach to a myoelectric hand T2 - 13TH International Conference on Rehabilitation Robotics Y1 - 2013 A1 - S. B. Godfrey A1 - A. Ajoudani A1 - M. G. Catalano A1 - G. Grioli A1 - A. Bicchi KW - Haptics KW - Robotics JF - 13TH International Conference on Rehabilitation Robotics CY - June 24-26, 2013, Seattle, WA. UR - 10.1109/ICORR.2013.6650377 ER - TY - CONF T1 - Teleimpedance Control of a Synergy-Driven Anthropomorphic Hand T2 - IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2013 Y1 - 2013 A1 - A. Ajoudani A1 - S. B. Godfrey A1 - M. G. Catalano A1 - G. Grioli A1 - N G Tsagarakis A1 - A. Bicchi KW - Haptics KW - Robotics JF - IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2013 CY - Tokyo, Japan ER - TY - JOUR T1 - Variable Impedance Actuators: a Review JF - Robotics and Autonomous Systems Y1 - 2013 A1 - B. Vanderborght A1 - A Albu-Schaeffer A1 - A. Bicchi A1 - E. Burdet A1 - D. G. Caldwell A1 - R. Carloni A1 - M. G. Catalano A1 - O. Eiberger A1 - W. Friedl A1 - G. Ganesh A1 - M. Garabini A1 - M. Grebenstein A1 - G. Grioli A1 - S. Haddadin A1 - H. Hoppner A1 - A. Jafari A1 - M. Laffranchi A1 - D. Lefeber A1 - F. Petit A1 - S. Stramigioli A1 - N G Tsagarakis A1 - M. Van Damme A1 - R. Van Ham A1 - L. C. Visser A1 - S. Wolf KW - Robotics KW - Soft robotics KW - Variable Impedance Actuators AB -

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.

VL - 61 UR - http://www.sciencedirect.com/science/article/pii/S0921889013001188 IS - 12 N1 -

Available online 6 August 2013

ER - TY - CONF T1 - Adaptive Synergies: an approach to the design of under-actuated robotic hands T2 - International Conference of Intelligent Robots and Systems - IROS 2012 Y1 - 2012 A1 - G. Grioli A1 - M. G. Catalano A1 - E. Silvestro A1 - S. Tono A1 - A. Bicchi KW - Robotics JF - International Conference of Intelligent Robots and Systems - IROS 2012 CY - Vilamoura, Algarve, Portugal ER - TY - CONF T1 - Adaptive Synergies for a Humanoid Robot Hand T2 - IEEE-RAS International Conference on Humanoid Robots Y1 - 2012 A1 - M. G. Catalano A1 - G. Grioli A1 - A. Serio A1 - E. Farnioli A1 - C. Piazza A1 - A. Bicchi KW - Robotics JF - IEEE-RAS International Conference on Humanoid Robots CY - Osaka, Japan N1 -

Best Paper Award

ER - TY - CONF T1 - Passive impedance control of a Qboid multi-DOF VSA-CubeBot manipulator T2 - International Conference of Robotics and Automation - ICRA 2012 Y1 - 2012 A1 - M. Mancini A1 - G. Grioli A1 - M. G. Catalano A1 - M. Garabini A1 - F. Bonomo A1 - A. Bicchi KW - Robotics JF - International Conference of Robotics and Automation - ICRA 2012 CY - Saint Paul, MN, USA ER - TY - CONF T1 - Towards variable impedance assembly: the VSA peg-in-hole T2 - IEEE-RAS International Conference on Humanoid Robots Y1 - 2012 A1 - L. Balletti A1 - A. Rocchi A1 - F. A. W. Belo A1 - M. G. Catalano A1 - M. Garabini A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - IEEE-RAS International Conference on Humanoid Robots CY - Osaka, Japan ER - TY - CONF T1 - A Variable Damping module for Variable Impedance Actuation T2 - International Conference of Robotics and Automation - ICRA 2012 Y1 - 2012 A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - F. A. W. Belo A1 - A. Di Basco A1 - N G Tsagarakis A1 - A. Bicchi KW - Robotics JF - International Conference of Robotics and Automation - ICRA 2012 CY - Saint Paul, MN, USA ER - TY - ADVS T1 - Variable Impedance Actuators: Moving the Robots of Tomorrow Y1 - 2012 A1 - B. Vanderborght A1 - A Albu-Schaeffer A1 - A. Bicchi A1 - E. Burdet A1 - D. G. Caldwell A1 - R. Carloni A1 - M. G. Catalano A1 - G. Ganesh A1 - M. Garabini A1 - G. Grioli A1 - S. Haddadin A1 - A. Jafari A1 - M. Laffranchi A1 - D. Lefeber A1 - F. Petit A1 - S. Stramigioli A1 - N G Tsagarakis A1 - M. Van Damme A1 - R. Van Ham A1 - L. C. Visser A1 - S. Wolf KW - Robotics JF - International Conference of Intelligent Robots and Systems - IROS 2012- Best Jubilee Video Award ER - TY - CONF T1 - Velvet fingers: A dexterous gripper with active surfaces T2 - International Conference of Intelligent Robots and Systems - IROS 2012 Y1 - 2012 A1 - V. Tincani A1 - M. G. Catalano A1 - E. Farnioli A1 - M. Garabini A1 - G. Grioli A1 - G Fantoni A1 - A. Bicchi KW - Robotics JF - International Conference of Intelligent Robots and Systems - IROS 2012 CY - Vilamoura, Algarve, Portugal ER - TY - CONF T1 - A decoupled Impedance observer for a Variable Stiffness Robot T2 - 2011 IEEE International Conference on Robotics and Automation Y1 - 2011 A1 - A. Serio A1 - G. Grioli A1 - I. Sardellitti A1 - N G Tsagarakis A1 - A. Bicchi KW - Robotics JF - 2011 IEEE International Conference on Robotics and Automation CY - Shangai, China ER - TY - CONF T1 - The Hand Embodied T2 - Automatica.it 2011 Y1 - 2011 A1 - A. Serio A1 - M. G. Catalano A1 - G. Grioli A1 - M Gabiccini A1 - A. Bicchi KW - Haptics KW - Robotics JF - Automatica.it 2011 CY - Pisa, Italy N1 -

poster presentation

ER - TY - CONF T1 - A Real-time Parametric Stiffness Observer for VSA devices T2 - 2011 IEEE International Conference on Robotics and Automation Y1 - 2011 A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - 2011 IEEE International Conference on Robotics and Automation CY - Shangai, China ER - TY - CONF T1 - Variable stiffness actuators: muscles for the next generation of robots T2 - Automatica.it 2011 Y1 - 2011 A1 - G. Grioli A1 - M. G. Catalano A1 - M. Garabini A1 - F. Bonomo A1 - A. Serio A1 - P Salaris A1 - F. A. W. Belo A1 - M. Mancini A1 - A. Bicchi A1 - A. Passaglia KW - Robotics JF - Automatica.it 2011 CY - Pisa, Italy N1 -

poster presentation

ER - TY - CONF T1 - VSA - CubeBot. A modular variable stiffness platform for multi degrees of freedom systems T2 - 2011 IEEE International Conference on Robotics and Automation Y1 - 2011 A1 - M. G. Catalano A1 - G. Grioli A1 - M. Garabini A1 - F. Bonomo A1 - M. Mancini A1 - N G Tsagarakis A1 - A. Bicchi KW - Robotics JF - 2011 IEEE International Conference on Robotics and Automation CY - Shangai, China ER - TY - CONF T1 - A Non-invasive Real-Time Method for Measuring Variable Stiffness T2 - Robotics Science and Systems Y1 - 2010 A1 - G. Grioli A1 - A. Bicchi KW - Robotics JF - Robotics Science and Systems CY - Zaragoza, Spain ER - TY - JOUR T1 - Rendering Softness: Integration of kinaesthetic and cutaneous information in a haptic device JF - Transactions on Haptics Y1 - 2010 A1 - E. P. Scilingo A1 - M. Bianchi A1 - G. Grioli A1 - A. Bicchi KW - Haptics KW - Robotics VL - 3 N1 -

Best Student Paper and Best Paper Award Finalist

ER - TY - CONF T1 - Validation of a Virtual Reality Environment to Study Anticipatory Modulation of Digit Forces and Position T2 - Eurohaptics 2010 Y1 - 2010 A1 - M. Bianchi A1 - G. Grioli A1 - E. P. Scilingo A1 - M. Santello A1 - A. Bicchi KW - Haptics KW - Robotics JF - Eurohaptics 2010 T3 - Lecture Notes in Computer Science CY - Amsterdam (The Netherlands) VL - 6192/2010 ER - TY - CONF T1 - VSA-HD: From the Enumeration Analysis to the Prototypical Implementation T2 - IEEE/RSJ International Conference on Intelligent RObots and Systems Y1 - 2010 A1 - M. G. Catalano A1 - G. Grioli A1 - F. Bonomo A1 - R. Schiavi A1 - A. Bicchi KW - Embedded Control KW - Robotics JF - IEEE/RSJ International Conference on Intelligent RObots and Systems CY - St. Louis MO USA ER - TY - CONF T1 - A Rough-Terrain, Casting Robot for the ESA Lunar Robotics Challenge T2 - Proc. IEEE/RSJ International Conference on Intelligent RObots and Systems Y1 - 2009 A1 - S. Alicino A1 - M. G. Catalano A1 - F. Bonomo A1 - F. A. W. Belo A1 - G. Grioli A1 - R. Schiavi A1 - A. Fagiolini A1 - A. Bicchi KW - Robotics AB -

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

JF - Proc. IEEE/RSJ International Conference on Intelligent RObots and Systems CY - St. Louis MO USA ER - TY - CONF T1 - Physical Human-Robot Interaction: Dependability, Safety, and Performance T2 - Proc. 10th Intl. Workshop Advanced Motion Control Y1 - 2008 A1 - A. Bicchi A1 - M. Bavaro A1 - G. Boccadamo A1 - D. De Carli A1 - R. Filippini A1 - G. Grioli A1 - M. Piccigallo A1 - A. Rosi A1 - R. Schiavi A1 - S. Sen A1 - G. Tonietti KW - Embedded Control KW - Physical Human-Robot Interaction (pHRI) KW - Robotics AB -

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.

JF - Proc. 10th Intl. Workshop Advanced Motion Control ER - TY - CONF T1 - VSA-II: A Novel Prototype of Variable Stiffness Actuator for Safe and Performing Robots Interacting with Humans T2 - Proc. IEEE Int. Conf. on Robotics and Automation Y1 - 2008 A1 - R. Schiavi A1 - G. Grioli A1 - S. Sen A1 - A. Bicchi KW - Robotics AB -

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.

JF - Proc. IEEE Int. Conf. on Robotics and Automation ER -