1. Research Division Honda Research Institute Japan Co., Ltd. 8-1 Honcho Wako Saitama 351–0188 Japan
2. Department of Systems and Control Engineering School of Engineering Tokyo Institute of Technology 2-12-1 Ookayama Meguro Tokyo 152–8552 Japan
3. Graduate Program for Embodiment Informatics Waseda University 2-4-12 Lambdax Bldg. 301, O-kubo Shinjuku-ku Tokyo 169-0072 Japan