1. School of Mechanical Engineering, Anhui University of Technology, Maanshan, China
2. School of Mechanical Engineering, Anhui Province Key Laboratory of Special Heavy Load Robot, Anhui University of Technology, Maanshan, China
3. School of Mechanical Engineering, Key Lab of Parallel Robot and Mechatronic System, Yanshan University, Qinhuangdao, China
4. School of Electrical Engineering, Key Lab of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, China