title: Foot placement modification for a biped humanoid robot with narrow feet.
abstract: This paper describes a walking stabilization control for a biped humanoid robot with narrow feet. Most humanoid robots have larger feet than human beings to maintain their stability during walking. If robot's feet are as narrow as humans, it is difficult to realize a stable walk by using conventional stabilization controls. The proposed control modifies a foot placement according to the robot's attitude angle. If a robot tends to fall down, a foot angle is modified about the roll axis so that a swing foot contacts the ground horizontally. And a foot-landing point is also changed laterally to inhibit the robot from falling to the outside. To reduce a foot-landing impact, a virtual compliance control is applied to the vertical axis and the roll and pitch axes of the foot. Verification of the proposed method is conducted through experiments with a biped humanoid robot WABIAN-2R. WABIAN-2R realized a knee-bended walking with 30 mm breadth feet. Moreover, WABIAN-2R mounted on a human-like foot mechanism mimicking a human's foot arch structure realized a stable walking with the knee-stretched, heel-contact, and toe-off motion.
authors.affiliation: Waseda Research Institute for Science and Engineering, Waseda University, No. 41-304, 17 Kikui-cho, Shinjuku-ku, Tokyo 162-0044, Japan.
authors.forename: Kenji
authors.identifier: 0000-0003-2300-6766
authors.initials: K
authors.lastname: Hashimoto
authors.affiliation: Graduate School of Science and Engineering, Waseda University, No. 41-304, 17 Kikui-cho, Shinjuku-ku, Tokyo 162-0044, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Hattori
authors.affiliation: Graduate School of Science and Engineering, Waseda University, No. 41-304, 17 Kikui-cho, Shinjuku-ku, Tokyo 162-0044, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Otani
authors.affiliation: Faculty of Engineering, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan ; Humanoid Robotics Institute (HRI), Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Hun-Ok
authors.initials: HO
authors.lastname: Lim
authors.affiliation: Humanoid Robotics Institute (HRI), Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan ; Department of Modern Mechanical Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.
authors.forename: Atsuo
authors.initials: A
authors.lastname: Takanishi
mesh_terms: D005528:Foot / Q000502:physiology*; D005684:Gait; D006801:Humans; D009038:Motion; D012371:Robotics / Q000295:instrumentation*; D016138:Walking