1. College of Mechanical Engineering, Zhejiang University of Technology, Liuxia Street, Xihu District, Hangzhou 310023, China
2. State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China
3. R&D Engineering Department, Wahaha Intelligent Robotics, Xiaoshan Economic and Technological Development Zone, Xiaoshan District, Hangzhou 311231, China