Integrated rotary compliant joint and its impedance-based controller for single-joint pressing massage robot

For the purpose of developing a lightweight massage robotic arm ensuring safe human-robot contact, reduction of large force caused by shocks, and accurate and stable force following, a compact, integrated rotary compliant joint is designed, and a simple single-joint pressing massage robot is constructed in order to verify the compliant joint's performance. Then, the impedance-based controller with joint torque control is presented, which is robust to unstructured environment during human-robot interaction, and is used to accomplish pressing massage by the single-joint robot. Experimental results show that the developed integrated rotary compliant joint is efficient to fulfill its function during robot pressing massage and is eligible for the construction of service robots in which safe human-robot interaction is necessary.