1. Center of Ultra-Precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150080, P. R. China
2. Key Lab of Ultra-Precision Intelligent Instrumentation, (Harbin Institute of Technology), Ministry of Industry and Information Technology, Harbin 150080, P. R. China
3. State Key Laboratory of Robotics and System, Harbin Institute of Technology, Harbin 150001, P. R. China