Force Sensorless Multi-functional Impedance Control for Rehabilitation Robot

As more robotic technology has been developed and implemented for rehabilitation training, the conventional rehabilitation methodology is expected to change and to have various functional modes other than Continuous Passive Movement (CPM). In this paper, the multifunctional training that are expected for the rehabilitation robot to provide is introduced, and the control algorithm to achieve these functional training is proposed. As the multi-functions of rehabilitation training are categorized based on the type of reaction force of the robot, force control of robot is required in the realization of the functions, and force sensorless methodology is employed in this paper taking into consideration of the expense of sensors and mechanical design. A upper limb rehabilitation robot is utilized in the experiments, and the performance of the proposed force sensorless control for multi-functional rehabilitation is verified through the experiments.