1Department of Mechanical Engineering, College of Science and Technology, Nihon University, 8 Kanda Surugadai, 1-Chome, Chiyoda-ku, Tokyo 101-8308, Japan
2Honda R&D Co., Ltd. Tochigi R&D Center, 4630 Shimotakanezawa, Haga-machi, Haga-gun, Tochigi 321-3393, Japan