1. School of Mechanical Engineering, Anhui Polytechnic University, Wuhu 241000, China
2. Anhui Key Laboratory of Advanced Numerical Control & Servo Technology, Wuhu 241000, China
3. Department of Mechanics, Tianjin University, Tianjin 300350, China
4. Wuhu Ruilong Robot Technology Co., Ltd., Wuhu 241000, China