Design and Control of a Rehabilitation Robot Manipulator for Head-Neck Orthopaedic Disorders

Abstract

This paper addresses the design and control of a dual-arm robot manipulator that can be used for the treatment of head-neck orthopaedic disorders. Each arm of this manipulator has six-degrees-of-freedom (DoF) serial RRRRU topological structure, four of which are actively actuated and two of which are passive. The head-neck model in harmony with this underactuated robot arm was designed as a 4-DoF serial manipulator. Although the system is deficient, all motions of the head-neck model subjected to rehabilitation can be fully performed due to the topology chosen for the arms; in other words, the kinematically closed-loop robotic system can move without blocking. In this study, kinematic analyses were performed separately for both the arms and the head-neck model, and the results were obtained analytically and semi-analytically. Then, the robotic system described with dynamic analysis was controlled by the computed torque control method. Here, the quasi-external forces/moments that supply the desired user-defined rehabilitation motions to the head-neck model are taken as the force/moment inputs for the dual-arm robot. The control of the robotic system was carried out to test the performance of the system according to the generated torques and the mobility of the rehabilitation robot.