JRM Vol.20 No.5 pp. 709-718
doi: 10.20965/jrm.2008.p0709


Arc Feet Effects on Stability Based on a Simple Oscillator-Driven Walking Model

Shinya Aoi*, Yuuki Sato**, and Kazuo Tsuchiya*

* Dept. of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan

** Dept. of Aeronautics and Astronautics, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan

February 6, 2008
August 7, 2008
October 20, 2008
bipedal walking, arc feet, oscillator, stability, Poincaré map

Lower-extremity movement in bipedal walking is characterized by a foot-rolling motion that includes heel-strike and toe-off. We investigated the dynamical influence of this movement on walking stability using a simple walking model that has a circular arc at the end of each leg. The leg is driven by a rhythmic signal from an internal oscillator to generate walking. We focused on stability characteristics due to the arc foot based on (1) the stability region for parameters such as mass distribution and walking speed, in which the circular arc radius is optimal when it is almost the same length as the leg to maximize the stable region and (2) the rate of convergence to stable walking, which is maximized by a circular arc radius of zero. These two conflicting results imply that the optimal radius of a circular arc for local stability is a trade-off between the two criteria, reflecting a dynamic feature of bipedal walking that should be considered in biped robot design.

Cite this article as:
Shinya Aoi, Yuuki Sato, and Kazuo Tsuchiya, “Arc Feet Effects on Stability Based on a Simple Oscillator-Driven Walking Model,” J. Robot. Mechatron., Vol.20, No.5, pp. 709-718, 2008.
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Last updated on Mar. 05, 2021