New paper on the Robotic Sixth Finger

It is our pleasure to announce a new publication regarding the Robotic Sixth Finger on the Robotics and Autonomous System Journal.

Title: Supernumerary robotic finger and mobile arm support: from grasp compensation to hemiparetic upper limb rehabilitation

Abstract

In this paper, we present the combination of our soft supernumerary robotic finger i.e. Soft-SixthFinger with a commercially available zero gravity arm support, the SaeboMAS. The overall proposed system can provide the needed assistance during paretic upper limb rehabilitation involving both grasping and arm mobility to solve task-oriented activities. The Soft-SixthFinger is a wearable robotic supernumerary finger designed to be used as an active assistive device by post stroke patients to compensate the paretic hand grasp. The device works jointly with the paretic hand/arm to grasp an object similarly to the two parts of a robotic gripper. The SaeboMAS is a commercially available mobile arm support to neutralize gravity effects on the paretic arm specifically designed to facilitate and challenge the weakened shoulder muscles during functional tasks. The proposed system has been designed to be used during the rehabilitation phase when the arm is potentially able to recover its functionality, but the hand is still not able to perform a grasp due to the lack of an efficient thumb opposition. The overall system also act as a motivation tool for the patients to perform task-oriented rehabilitation activities.

With the aid of proposed system, the patient can closely simulate the desired motion with the non-functional arm for rehabilitation purposes, while performing a grasp with the help of the Soft-SixthFinger. As a pilot study we tested the proposed system with a chronic stroke patient to evaluate how the mobile arm support in conjunction with a robotic supernumerary finger can help in performing the tasks requiring the manipulation of grasped object through the paretic arm. In particular, we performed the Frenchay Arm Test (FAT) and Box and Block Test (BBT). The proposed system successfully enabled the patient to complete tasks which were previously impossible to perform.

system_concept

New paper on Transaction on Neural System and Rehabilitation Engineering

While attending at the Consortium Meeting of the EU project SoftPro, we are happy to announce our new paper on the Robotic Sixth Finger appeared in Transaction on Neural System and Rehabilitation Engineering. The paper is part of the Special Issue on Wearable Robotics for Motion Assistance and Rehabilitation.

Compensating Hand Function in Chronic Stroke Patients Through the Robotic Sixth Finger  

G. Salvietti, I. Hussain, D. Cioncoloni, S. Taddei, S. Rossi, D. Prattichizzo

A novel solution to compensate hand grasping abilities is proposed for chronic stroke patients. The goal is to provide the patients with a wearable robotic extra-finger that can be worn on the paretic forearm by means of an elastic band. The proposed prototype, the Robotic Sixth Finger, is a modular articulated device that can adapt its structure to the grasped object shape. The extra-finger and the paretic hand act like the two parts of a gripper cooperatively holding an object. We evaluated the feasibility of the approach with four chronic stroke patients performing a qualitative test, the Frenchay Arm Test. In this proof of concept study, the use of the Robotic Sixth Finger has increased the total score of the patients of 2 points in a 5 points scale. The subjects were able to perform the two grasping tasks included in the test that were not possible without the robotic extra-finger. Adding a robotic opposing finger is a very promising approach that can significantly improve the functional compensation of the chronic stroke patient during everyday life activities.

tnsre

Paper bibtex file:

@article{SaHuCiTaRoPr-TNSRE-17,
Author = {Salvietti, G. and Hussain, I. and Cioncoloni, D. and Taddei, S. and Rossi, S. and Prattichizzo, D.},
Title = {Compensating Hand Function in Chronic Stroke Patients Through the Robotic Sixth Finger},
Journal = {Transaction on Neural System and Rehabilitation Engineering},
Volume = {25},
Number = {2},
Pages = {142–150},
Year = {2017}
}

Our new Soft-SixthFinger published in Robotics and Automation Letters and presented @Augmented-Human Conference

The paper on Robotics and Automation Letters presents the Soft-SixthFinger, a wearable robotic extra-finger designed to be used by chronic stroke patients to compensate for the missing hand function of their paretic limb. The extra-finger is an under actuated bimanual
modular structure worn on the paretic forearm by means of an elastic band. The device and the paretic hand/arm act like the two parts of a gripper working together to hold an object. The patient can control the flexion/extension of the robotic finger through the eCap, an Electromyography (EMG) interface embedded in a cap. The user can control the device contracting the frontalis muscle by moving his or her eyebrows upwards. The Soft-SixthFinger has been designed as tool that can be used by chronic stroke patients to compensate for grasping in many Activities of Daily Living (ADL). It can be wrapped around the wrist and worn as a bracelet ecapwhen not used. The light weight and the complete wireless connection with the EMG interface guarantee a high portability and wearability. We tested the device with qualitative experiments involving six chronic stroke patients. Results show that the proposed system significantly improves the performance of the considered tests and the autonomy in ADL.

We are in Geneve right now to present our Soft-SixthFinger @Augmented Human Conference. Pics of the event are available here.

 

Our paper “Compensating Hand Function in Chronic Stroke Patients Through the Robotic Sixth Finger” on IEEE Transaction on Neural Systems and Rehabilitation Engineering

BBboardA novel solution to compensate hand grasping abilities has been proposed for chronic stroke patients. The goal is to provide the patients with a wearable robotic extra-finger that can be worn on the paretic forearm by means of an elastic band. The proposed prototype, the Robotic Sixth Finger, is a modular articulated device that can adapt its structure to the grasped object shape. The extra-finger and the paretic hand act like the two parts of a gripper cooperatively holding an object. We evaluated the feasibility of the approach with four chronic stroke patients performing a qualitative test, the Frenchay Arm Test. In this proof of concept study, the use of the Robotic Sixth Finger has increased the total score of the patients of 2 points in a 5 points scale. The subjects were able to perform the two grasping tasks included in the test that were not possible without the robotic extra-finger. Adding a robotic opposing finger is a very promising approach that can significantly improve the functional compensation of the chronic stroke patient during everyday life activities.

The early access version of the paper can be found here.

Paper on “THE” Project published on Physics of Life Reviews

An article summarising the results of the four years EU project “The Hand Embodied – THE “ has been published on the prestigious journal Physics of Life Reviews. Here the link to the article. As University of Siena, we have contributed to the modelling of hand synergies and we have studied a systematic way to transfer human hand skills onto robotic hands. These results can be found here.

Abstract of the paper
phyLif

The term ‘synergy’ – from the Greek synergia – means ‘working together’. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro- rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments.

The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project “The Hand Embodied” (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.

The Robotic Sixth Finger: a wearable extra limb to compensate hand function in chronic post stroke patient

blog
Fig. 1. The Robotic Sixth Finger concept. The device is worn like a bracelet and pops up when needed.

This post summarises our research on wearable extra fingers. We started to investigate how to enhance the capability of the human hand by means of wearable robots in 2011 [1]. The goal was to integrate the human hand with an additional robotic finger as represented in Fig. 1. We firstly investigate the potentials of extra-finger in healthy subjects. Such devices could give humans the possibility to manipulate objects in a more efficient way, enhancing our hand grasping dexterity/ability. The first prototype has been presented in [2] together with several examples of the extra-finger applications. Together with the design issues related to portability and wearability of the devices, another critical aspect was integrating the motion of the extra–fingers with that of the human hand. In [3], we presented a mapping algorithm able to transfer to the extra–fingers a part or the whole motion of the human hand. A commercial dataglove was used to measure the hand configuration during a grasping task. A video is available here. Although this control approach guarantees a reliable tracking of the human hand, there was two main drawbacks to be solved. First, the user lacked a feedback of the robotic finger status and could only perceive the force

device-1_red
Fig. 2. The Robotic Sixth Finger together with the vibrotactile interface ring.

exerted by the device mediated by the grasped object. The second problem was related to the approaching phase of the grasp. In fact, the algorithm presented in [3] considers the motion of the whole hand to compute the motion of the extra finger, thus limiting the possibility of the user to make fine adjustments to adapt the finger shape to that of the grasped object. In [4] we addressed these issues by introducing a vibrotactile interface that can be worn as a ring. The human user receives information through the vibrotactile interface about the robotic finger status in terms of contact/no contact with the grasped object and in terms of force exerted by the device. Regarding the grasp approaching phase, we introduced a new control strategy that enables the finger to autonomously adapt to the shape of the grasped object.

Setup_icorr_robotic
Fig. 3. The Robotic Sixth Finger for hand grasping compensation in chronic stroke patients.

The experience gained with healthy subjects was fundamental for the development of Robotic Sixth Finger for compensating hand function in chronic stroke patients. We proposed to use a robotic the Robotic Sixth Finger together with the paretic hand/arm, to constrain the motion of the object. The device can be worn on the user’s forearm by means of an elastic band. The systems acts like a two-finger gripper, where one finger is represented by the Robotic Sixth Finger, while the other by the patient’s paretic limb. The patient can regulate the finger flexion/extension through a wearable switch embedded in a ring worn on the healthy hand. Two possible predefined motions can be chosen to obtain either a precision or a power grasp. In addition to the switch, the proposed ring interface also embeds a vibrotactile motor able to provide the patient with information about the force exerted by the device. The preliminary results with patients are presented in [5] and a video is available here.

Related publications

[1] O. A. Atassi, “Design of a robotic sixth finger for grasping enhancement,” Master’s thesis, Universita` degli Studi di Siena (advisor: Domenico Prattichizzo), December 2011.

[2] D. Prattichizzo, M. Malvezzi, I. Hussain, G. SalviettiThe Sixth-Finger: a Modular Extra-Finger to Enhance Human Hand Capabilities. In Proc. IEEE Int. Symp. in Robot and Human Interactive Communication, Pages 993-998, Edinburgh, United Kingdom, August 2014.

[3] D. Prattichizzo, G. Salvietti, F. Chinello, M. MalvezziAn Object-based Mapping Algorithm to Control Wearable Robotic Extra-Fingers. In Proc. IEEE/ASME Int. Conf. on Advanced Intelligent Mechatronics, Pages 1563-1568, Besançon, France, July, 2014.

[4] I. Hussain, L. Meli, C. Pacchierotti, G. Salvietti, D. PrattichizzoVibrotactile haptic fedback for intuitive control of robotic extra fingers. In Proc. IEEE World Haptics Conference (WHC), Chicago, IL, June, 2015.

[5] I. Hussain, G. Salvietti, L. Meli, C. Pacchierotti, D. PrattichizzoUsing the robotic sixth finger and vibrotactile feedback for grasp compensation in chronic stroke patients. In Proc. IEEE/RAS-EMBS International Conference on Rehabilitation Robotics (ICORR), Singapore, Republic of Singapore, 2015. [Finalist for the Best Student Paper Award]

[6] D. Prattichizzo. The interplay between humans and robots in grasping. In Proc. International Symposium on Robotic Research, Sestri Levante, Italy, September, 2015

[7] I. Hussain, G. Salvietti, M. Malvezzi and D. Prattichizzo. Design guidelines for a wearable robotic extra-finger. In proc. IEEE Int. Forum on Research and Technology for Society and Industry, Turin, Italy September, 2015

Chapter on HANDS.DVI project is on-line

The chapter HANDS.DVI: A Device-Independent Programming and Control Framework for Robotic Hands is now available on-line within the book “Gearing Up and Accelerating Cross‐fertilization between Academic and Industrial Robotics Research in Europe:  Springer Tracts in Advanced Robotics” http://link.springer.com/chapter/10.1007/978-3-319-03838-4_10

9783319038377