1. Faculty of Systems Engineering, Wakayama University, Wakayama, Japan
2. Graduate School of Systems Engineering, Wakayama University, Wakayama, Japan
3. Department of Robotics, Faculty of Engineering, Kindai University, Higashi-Hiroshima, Japan
4. Electronics, Information and Communication Engineering Course, Faculty of Advanced Science and Technology, Ryukoku University, Otsu, Japan
5. Department of Mechanical Engineering, Graduate School of Engineering, Kobe University, Kobe, Japan