1. UM‐SJTU Joint Institute Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 China
2. Key Laboratory of Mechanism and Equipment Design of Ministry of Education Tianjin University Tianjin 300350 China
3. School of Mechanical Engineering Tianjin University Tianjin 300350 China
4. Department of Advanced Manufacturing and Robotics College of Engineering Peking University Beijing 100871 China