1. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China
2. Institutes for Robotics and Intelligent Manufacturing Chinese Academy of Sciences Shenyang 110169 China
3. University of Chinese Academy of Sciences Beijing 100049 China
4. School of Automation and Electrical Engineering Shenyang Ligong University Shenyang Liaoning 110159 China