1. Key Laboratory of Micro-Systems and Micro-Structure Manufacturing (Ministry of Education) and School of Mechatronics Engineering, Harbin Institute of Technology, Xidazhi, 92, Harbin 150001, P.R. China
2. School of Mechatronics Engineering, Heilongjiang East University, Harbin 150066, China
3. The Ohio State University, San Jose, California 95120, United States