Kinematic, Dynamic Analysis and Control of 3 DOF Upper-limb Robotic Exoskeleton

Abstract

The purpose of this paper is to analyse complete kinematics and dynamics, along with the joint position analysis of a 3 DOF upper-limb robotic exoskeleton. This paper also investigates the feasibility of computed torque control for an exoskeleton device. After studying the biomechanics of human upper-limb, a 3 DOF exoskeleton has been designed. The development of upper limb and lower extremity robotic exoskeletons has emerged as a way to improve the quality of life as well as act as a primary rehabilitation device for the individuals suffering from stroke or spinal cord injury. The designed exoskeleton presents three of the most basic movements of the human arm that facilitate activities of daily living (ADL). The design parameters are taken similar to the parameters of the upper-limb of a normal human being. Computed torque control (CTC) is applied to the system in order to actuate the system to the desired joint positions. The exoskeleton exhibits shoulder abduction/adduction, extension/flexion and elbow extension/flexion motions. For better understanding of exoskeleton motion capabilities, the exoskeleton workspace is visualized and the workspace is obtained using MATLAB. The results clearly show that the CTC control successfully reduces the error in the exoskeleton joint positions.