[WEB PAGE] Big Thumbs Up: Robotic Finger Controlled by Feet Tested by UK Scientists

“Sometimes five fingers per hand is just not enough, this is when an extra thumb idea comes quite handy” said UK researchers who have attempted to improve human motor performance.

 

Dani Clode, a designer and researcher at University College London’s Plasticity Lab, has developed a 3D-printed prosthetic that is controlled with pressure exerted with the big toes.

The robotic finger, which the scientists call the Third Thumb, was designed to extend the natural repertoire of hand movements. A group of people wore the Third Thumb during an observed augmentation test and were studied for changes in motor control and embodiment of the prosthetic.

Our first Third Thumb paper is now available as pre print! Neurocognitive consequences of hand augmentation. #thirdthumb @PlasticityUCL https://t.co/DxcuN6LwBx pic.twitter.com/jVZ3ZfiDWY

— Dani Clode (@DaniClode) June 17, 2020

The scientists also examined how the sensorimotor and body representation of the Thumb changed following the training.

During the 5 days of using the robotic finger, the participants were tasked with picking up wine glasses and building Jenga towers. Another task included holding a plastic cup while extracting a marble with a spoon.

The findings of the study showed that after training, those using the thumb would show fewer differences in brain activity patterns for individual fingers. In other words, the part of the brain – activated when people move their fingers – has a weakened representation of the hand after training with the thumb.

The scientists concluded that technologies designed to augment human motor abilities hold a promise for both disabled and healthy communities.

“Here, we demonstrate that successful integration of motor augmentation can be achieved, with potential for flexible use, reduced cognitive reliance and increased sense of embodiment. Importantly, though, such successful human-robot integration may have consequences on some aspect of body representation and motor control which need to be considered and explored further,” the study said.

 

via Big Thumbs Up: Robotic Finger Controlled by Feet Tested by UK Scientists – Sputnik International

[Abstract] A soft supernumerary robotic finger and mobile arm support for grasping compensation and 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.

Source: A soft supernumerary robotic finger and mobile arm support for grasping compensation and hemiparetic upper limb rehabilitation

[ARTICLE] Using the Robotic Sixth Finger and Vibrotactile Feedback for Grasp Compensation in Chronic Stroke Patients – Full Text PDF

Abstract

This paper presents a wearable robotic extra finger used by chronic stroke patients to compensate for the missing hand functions of the paretic limb. The extra finger is worn on the paretic forearm by means of an elastic band, and it is coupled with a vibrotactile ring interface worn on the healthy hand. The robotic finger and the paretic hand act like the two parts of a gripper working together to hold an object. The human user is able to control the flexion/extension of the robotic finger through a switch placed on the ring, while being provided with vibrotactile feedback about the forces exerted by the robotic finger on the environment. To understand how to control the vibrotactile interface to evoke the most effective cutaneous sensations, we carried out perceptual experiments to evaluate its absolute and differential thresholds. Finally, we performed a qualitative experiment, the Franchay Arm Test, with a chronic post-stroke patient presenting a partial loss of sensitivity on the paretic limb. Results show that the proposed system significantly improves the performance of the considered test.

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