1. State Key Laboratory of Fluid Power and Mechatronic Systems, School of Mechanical Engineering, Zhejiang University, Hangzhou, China
2. Hong Kong University of Science and Technology (HKUST), Hong Kong, China
3. State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou, China
4. School of Electrical Engineering, Zhejiang University, Hangzhou, China
5. Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China