SMA Actuated Finger Exoskeleton Device for Rehabilitation of Acute Paresis Patient

Functional recovery of upper limb after stroke is crucial to restore the ability to perform activities of daily living (ADL). This paper presents a robotic rehabilitation approach based on repetitive exercise aimed to help stroke survivors relearn the skills of finger flexion and extension at the comfort of their home. The finger rehabilitation device deploys Shape Memory Alloy (SMA) wires as an actuation approach to deliver three degrees of freedom per finger module. The advantages and challenges of using SMA wires rather than conventional actuators are discussed. A prototype of the finger rehabilitation device was built using PLA material and experiments have been conducted for the purposes of feasibility study. Tests conducted on the wires suggest that it has to have sufficient weight and also has to be stretching at high temperature rather than room temperature in order to have an optimum range of recovery.