1. Dept. of Intelligent Mech. Eng., National Institute of Technology, Wakayama College.
2. Graduate Student, Dept. of Mech. & Physical Eng., Osaka City Univ.
3. Osaka Kyoiku University.
4. Div. of Mech. Eng., Osaka Metropolitan Univ.
5. Hiroshima Prefectural Technology Research Institute Western Region Industrial Research Center