1. Research Institute of Intelligent Control and Systems, Harbin Institute of Technology, Harbin 150001, China.
2. Ningbo Institute of Intelligent Equipment Technology Company Ltd., Ningbo 315201, China.
3. Research Institute of Intelligent Control and Systems, Harbin Institute of Technology, Harbin 150001, China, and also with the Department of Mechanical Engineering, University of Victoria, Victoria, BC V8W 3P6, Canada.
4. Research Institute of Intelligent Control and Systems, Harbin Institute of Technology, Harbin 150001, China. (e-mail: hjgao@hit.edu.cn)