1. College of Electrical Engineering, Zhejiang University, Hangzhou 310027, People’s Republic of China
2. School of Automation and Electrical Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, People’s Republic of China
3. State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, People’s Republic of China