Design of a Cable-Driven Interactive Rehabilitation Device with 3D Trajectory Tracking and Force Feedback

The design of a cable-driven interactive rehabilitation device with 3D trajectory tracking and force feedback is presented in this paper. This device is designed for the upper limb active training, including muscle strengthening and full range of 3D space motion training. Unlike the traditional end-effector robot, this device only offers tensile force to the user by grasping the handle, which attached to the end of the cable. The force value, force direction and handle position are real-time monitored by three force sensors and an encoder. This enables more interesting interactive training between the user and the device. The mechanical design and control system design are presented in detail. The motion space of the device and the human model are analyzed. The PID force controller was designed to keep the tensile force accurately tracking given trajectories. Experiment with different PID parameters was carried out and the results show that the designed PID controller has relatively optimal control performance, with sine and square wave tracking errors are respectively -0.018 +/- 0.56 N and -0.11 +/- 3.45 N. The proposed device is potentially to provide physical fitness training, in addition to the routine training therapy in daily life.