Design of Elbow Exoskeleton with Wireless System Control for Post Stroke Flexion-Extension Rehabilitation

Abstract

In this paper we proposed a rehabilitation system that assists therapists to restore motor function by repetitive flexion-extension movement using robotic technology. The sys-tem is an elbow exoskeleton that can be controlled based on elbow rotation angle and angular velocity. The system also equipped with wireless communication to give therapists an ability to determine the trajectory of motor movement patterns and speed. For speed control, therapists need to input Pulse Width Modulation (PWM) value by Android application that conducts 100% accuracy to communicate the PWM value to microcontroller through bluetooth connection. INA226 sensor used by the system for measuring current value in order to detect the voluntary movement that occured in subject's arm. Proportional Integral Derivative control (PID) used in order to achieve a predetermined trajectory value and maintain the Rotation per Minute (RPM) of the DC motor. As a result, the system can reach the target for fulfill 120-degree movement with 83.3% accuracy with passive hand and 100% accuracy with active arm condition. The measure of the sensor is used to analyze the rehabilitation process quantitatively and determine future treatment. This method expected can help patients to get intensive rehabilitation and make it easier for therapists to evaluate and rehabilitate patients.