Design and Control of a Novel Six Degrees-of-Freedom Desktop Upper Limb Rehabilitation Robot

Abstract

This paper presents the design, analysis, and development of a novel six degrees-of-freedom (6DOF) desktop upper limb rehabilitation robot. The upper limb rehabilitation robot is mainly composed of the omnidirectional mobile platform, armrest, and 3DOF wrist rehabilitation mechanism. The forward and inverse kinematics and Jacobian matrix of the upper limb rehabilitation robot are derived based on the kinematics of a rigid body, and its working space is also analyzed based on arm kinematics. The forward and inverse kinematics of the arm are derived based on the D–H method. A new control strategy and algorithm were developed based on the robot system's hardware structure and arm model. These were employed in simulated rehabilitation experiments on both a single joint and multiple joint linkages. The experimental results indicate that the maximum error for single-joint rehabilitation is 6.123 deg, while for multiple joint linkages, it is 5.323 deg. Therefore, the control strategy and control algorithm can complete the corresponding rehabilitation training. This 6DOF desktop upper limb rehabilitation robot can provide passive rehabilitation training for patients in the early stages of paralysis.