1. Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China
2. State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang, China
3. Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control and the National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China