CHARACTERISTICS OF THE ROBOTIC JOINT OF A 9-DOF UPPER LIMB REHABILITATION ROBOT DRIVEN BY PNEUMATIC MUSCLES

Abstract

This paper presents a wearable exoskeleton upper limb rehabilitation robot that consists of eight active joints and one passive joint. Each active joint is driven by two pneumatic muscles (PMs) in opposing pair configuration and each PM drives the joint through a steel wire with a flexible sleeve and a tension device. These factors incorporate with characteristics of PM make the rehabilitation robot system very complex (nonlinear, time-varying, and time-delay). In this paper, the friction force and characteristics of open-loop control of one of the robotic joints has been studied. The quasi-static model of the robotic joint have been established based on experimental methods. In addition, the performances of three control modes have also been researched. These works would be helpful to the future work such as the control of the rehabilitation robot.