Passive Walking Biped Model with Dissipative Contact and Friction Forces

The main purpose of this paper is to present a new planar dynamic model of the biped robot-walking with the supporting foot slippage and contact-impact forces. In contrast to McGeer’s passive dynamic models, normal forces and frictional forces acting on the feet and ground have been taken into account in the proposed model. The equations of motion and of the passive dynamic biped are obtained by using the Standard Lagrange multiplier method. The dynamics equations are obtained by forward dynamics. The normal forces acting on the feet of the passive biped are described based on the viscoelastic contact model. In turn, the frictional forces and the slippage is solve by the equations of Bengisu law for dry friction. Finally, results are validated with experimental results of the literature.