1. State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou 310027, People’s Republic of China
2. Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, Hangzhou 310027, People’s Republic of China
3. Department of Mechanics, Zhejiang University, Hangzhou 310027, People’s Republic of China