1. College of Mechanical Engineering, Yanshan University, Qinhuangdao, P.R. China
2. Parallel Robot and Mechatronic System Laboratory of Hebei Province, Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education, Yanshan University, Qinhuangdao, Hebei, P.R. China
3. Hebei Hanguang Industry CO., LTD, Hebei, P.R. China