1. School of Mechanical Engineering, Anhui University of Technology, Maanshan, Anhui 243002, P. R. China
2. Anhui Province Key Laboratory of Special Heavy Load Robot, Maanshan, Anhui 243032, P. R. China
3. Anhui Province Engineering Laboratory of Intelligent Demolition Equipment, Maanshan, Anhui 243032, P. R. China
4. School of Mechanical Engineering, Southeast University, Nanjing, Jiangsu 211189, P. R. China