Multi-Arm lower-limb rehabilitation robot for motor coordination training after stroke

The number of stroke patients is rapidly increasing in the elderly society, which leads to growing demand for lower limb rehabilitation training. Currently, one patient needs two or more therapists for assistance during gait training. It results in the shortage of therapists' population, furthermore, heavy works load on the therapist. The emerging robotic technologies provide a solution to assist the therapist, and a number of corresponding researches have been reported. However, most of the existing rehabilitation robots adopt single-arm or double-arm structure, which pays less attention on motor coordination training for the stroke patients. Here, a four-arm rehabilitation robot (FARR) is proposed to assist the hemiplegic patient for motor coordination training. First, the rehabilitation demand is analysed and the corresponding robot mechanism is designed. Then, the kinematics of the robot based on the D-H expression is constructed, and the workspace is obtained. Thirdly, the speed control strategy and the cooperative control for gait training are constructed. The experiment of speed response verifies the superior tracking performance of the robotic joints, and the experiment of using the robot for gait training by a simulated subject is performed. These results prove the feasibility of the designed robot.