1. Department of Mechanical Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan e-mail:
2. Department of Mechanical Engineering, Graduate School, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan
3. LG Technology Department, Linear Technology Center, NSK Ltd., 12 Kirihara, Fujisawa, Kanagawa 252-0811, Japan
4. Research Department, Linear Technology Center, NSK Ltd., 12 Kirihara, Fujisawa, Kanagawa 252-0811, Japan