Design and control of anthropomorphic BIT soft arms for TCM remedial massage

For reproducing the manipulation of TCM remedial massage and meanwhile guaranteeing safety, a 4-DOF anthropomorphic BIT soft arm with integrated elastic joints is developed, and a passivity-based impedance control is used. Due to their series elasticity, the integrated joints may minimize large forces which occur during accidental impacts and, further, may offer more accurate and stable force control and a capacity for energy storage. Then, human expert's fingertip force curve in the process of massage therapy is acquired in vivo by a dedicated measurement device. Three massage techniques, pressing, kneading and plucking, are implemented by the soft arm, respectively, on torso model in vitro and on human body in vivo. Experimental results show that the developed robotic arm can effectively imitates the TCM remedial massage techniques.