A Modular Soft Robotic Exoskeleton for Active Hand Rehabilitation after Stroke

This paper presents the design and components of a modular soft exoskeleton for an active hand rehabilitation in people who has suffered a stroke. Most of the exoskeletons designs in which soft technologies are incorporated do not allow movement of the thumb. Our design allows their user to flex and stretch the index finger, the middle finger and the thumb repeatedly with the possibility to train their memory movement by picking and releasing. This was achieved through a soft exoskeleton-like glove design fabricated with a 3D printer with flexible materials. The overall weight of this Soft Exoskeleton-like glove 155 g, not including the battery of 6V, the electronic components and the microcontroller which are placed in the forearm and have total weight of 159 g. Our device is able to provide the forces of 3,9N in cylindric grasp position and 1,6N in precision grasp. These movements are possible because the thumb can move according to the grasping. This could allow future users to train and rehabilitate outside of a specialized center for more frequent training by doing repetitive exercise.

I. Introduction

In Peru there is currently an estimated population of 3 593 054 older adults [1], in which more than 6.8% have suffered a stroke and only 20% manage to receive and complete physical rehabilitation of muscle paralysis because only private institutions have the proper equipment for rehabilitation focused on the recovery of hand movement [2] [3]. Besides in medical centers of Peru, there are no rehabilitation devices focused on the recovery of the movements of the fingers of the hands after suffering a stroke. Usually, to treat these problems, it is required to go through an arduous rehabilitation process [4], which focuses on repeating certain muscular movements in the fingers of the hand with the help of a physician, in order to recover movement little by little. Many times, these exercises are not completed because of the lack of specialized physicians and patient's motivation to attend all the sessions.