1. Graduate School of Engineering, Department of Design and Media TechnologyIwate University, 4‐3‐5, Ueda Morioka Iwate 020‐8551 Japan
2. Faculty of EngineeringFukui University, 3‐9‐1, Bunkyo Fukui Fukui 910‐8507 Japan
3. Manufacturing Study DepartmentToyota Motor East Japan, 1, Nishinemoriyama, Kanegasaki Isawa Iwate 029‐4503 Japan
4. Faculty of Science and EngineeringIwate University, 4‐3‐5, Ueda Morioka Iwate 020‐8551 Japan