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The elastic contact influences on passive walking gaits

Published online by Cambridge University Press:  02 December 2010

Feng Qi
Affiliation:
School of Aerospace, Tsinghua University, Beijing, 100084, P.R. China
Tianshu Wang*
Affiliation:
School of Aerospace, Tsinghua University, Beijing, 100084, P.R. China
Junfeng Li
Affiliation:
Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, P.R. China
*
*Corresponding author. E-mail: tswang@tsinghua.edu.cn

Summary

This paper presents a new planar passive dynamic model with contact between the feet and the ground. The Hertz contact law and the approximate Coulomb friction law were introduced into this human-like model. In contrast to McGeer's passive dynamic models, contact stiffness, contact damping, and coefficients of friction were added to characterize the walking model. Through numerical simulation, stable period-one gait and period-two gait cycles were found, and the contact forces were derived from the results. After investigating the effects of the contact parameters on walking gaits, we found that changes in contact stiffness led to changes in the global characteristics of the walking gait, but not in contact damping. The coefficients of friction related to whether the model could walk or not. For the simulation of the routes to chaos, we found that a small contact stiffness value will lead to a delayed point of bifurcation, meaning that a less rigid surface is easier for a passive model to walk on. The effects of contact damping and friction coefficients on routes to chaos were quite small.

Type
Articles
Copyright
Copyright © Cambridge University Press 2010

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References

1.Fallis, G. T., Walking Toy. U.S. Patent No. 376588 (United States Patent Office, Alexandria, VA, 1888).Google Scholar
2.McGeer, T., “Passive dynamic walking,” Int. J. Robot. Res. 9, 6282 (1990).Google Scholar
3.McGeer, T., “Passive dynamic walking with knees,” Proc. IEEE Conf. Robot. Autom. 2, 16401645 (1990).CrossRefGoogle Scholar
4.Garcia, M., Chatterjee, A., Ruina, A. and Coleman, M., “The simplest walking model: Stability, complexity, and scaling,” J. Biomech. Eng. 120 (2), 281288 (1998).Google Scholar
5.Goswami, A., Thuilot, B. and Espiau, B., “A study of the passive gait of a compass-like biped robot: Symmetry and chaos,” Int. J. Robot. Res. 17, 12821301 (1998).Google Scholar
6.Kurz, M. J., Judkins, T. N., Arellano, C. and Scott-Pandorf, M., “A passive dynamic walking robot that has a deterministic nonlinear gait,” J. Biomech. 40 (4), 617656 (2008).Google Scholar
7.Coleman, M. J. and Ruina, A., “An uncontrolled walking toy that cannot stand still,” Phys. Rev. Lett. 80 (16), 3658 (1998).Google Scholar
8.Kuo, A. D., “Stabilization of lateral motion in passive dynamic walking,” Int. J. Robot. Res. 18, 917930 (1999).Google Scholar
9.Wisse, M., Schwab, A. L. and Linde, R. Q. V., “A 3D passive dynamic biped with yaw and roll compensation,” Robotica 19 (03), 275 (2001).Google Scholar
10.Collins, S. H., Wisse, M. and Ruina, A., “A three-dimensional passive-dynamic walking robot with two legs and knees,” Int. J. Robot. Res. 20, 607615 (2001).Google Scholar
11.Narukawa, T., Yokoyama, K., Takahashi, M. and Yoshida, K., “A Simple 3D Straight-Legged Passive Walker with Flat Feet and Ankle Springs,” IEEE/RSJ International Conference on Intelligent Robots and Systems, 2008 (IROS 2008) pp. 2952–2957.Google Scholar
12.Wisse, M., Schwab, A. L. and van der Helm, F. C. T., “Passive dynamic walking model with upper body,” Robotica 22 (06), 681 (2004).Google Scholar
13.Safa, A. T., Saadat, M. G. and Naraghi, M., “Passive dynamic of the simplest walking model: Replacing ramps with stairs,” Mech. Mach. Theory 40 (7), 10271034 (2007).Google Scholar
14.Ning, L., Junfeng, L. and Tianshu, W., “The effects of parameter variation on the gaits of passive walking models: Simulations and experiments,” Robotica 27 (04), 511528 (2009).Google Scholar
16.Johnson, K. L., Contact Mechanics (Cambridge University Press, Cambridge, UK, 1985).Google Scholar
18.McGeer, T., “Passive bipedal running,” R. Soc. Lond. Proc. Ser. B 240, 107134 (1990).Google Scholar
19.Wu, Q. and Sabet, N., “An experimental study of passive dynamic walking,” Robotica 22 (3), 251 (2004).Google Scholar