A Wearable Rehabilitation Robotic Hand Driven by PM-TS Actuators

Abstract

Robotic-assisted therapy is of great benefit to the recovery of motor function for the patients survived from stroke. However there have been few emphases on the patients' hand training/exercise during the rehabilitation process. The goal of this research is to develop a novel wearable device for robotic assisted hand therapy. Unlike the traditional agonist/antagonist PM actuator, we propose a new PM-TS actuator comprising a Pneumatic Muscle (PM) and a Torsion Spring (TS) for joint drive. Based on the proposed PM-TS actuator, we design a robotic hand which is wearable and provides assistive forces required for finger training. The robotic hand has two distinct degrees of freedom at the metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints. The variable integral PID (VIPID) controller was designed to make the joint angle of robotic hand can accurately track a given trajectory. The results show that the VIPID controller has better performance than the conventional PID controller. The proposed rehabilitation robotic hand is potentially of providing supplemental at-home therapy in addition to the clinic treatment.