1. School of Mechanical, Electronic and Industrial Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
2. School of Engineering and Built Environment, Glasgow Caledonian University, Glasgow G4 0BA, UK
3. School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China
4. The State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, China