1. Mechanical System Research Laboratory, Industrial Technology Research Institute, Hsinchu 31040, Taiwan
2. Department of Mechanical Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan
3. Department of Mechanical Engineering, Minghsin University of Science and Technology, Hsinfong, Hsinchu 30401, Taiwan
4. Department of Mechanical Engineering, Nippon Institute of Technology, Saitama 345-8501, Japan