1. Platform Development Div., Development Unit, Fujitsu Connected Technologies Limited, 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki, Kanagawa, 211-8570, Japan
2. Division of Human Mechanical Systems and Design, Faculty of Engineering, Hokkaido University, N13W8, Sapporo, Hokkaido, 060-8628, Japan