On the Dynamics of a Biped upon a Moving Rough Plane

We consider the planar problem of the dynamics of a body moving along a horizontal with two legs in contact with a rough horizontal plane. Possible types of movements of the body are discussed depending on the acceleration of the support: relative equilibrium, sliding on two legs, lifting off one leg without sliding on the other, lifting off one leg while sliding on the other. Based on the results obtained, it is shown that, when sliding on two legs, the friction force is generally anisotropic. This makes it possible to transport the body due to simple vibrations of the plane, for example, harmonic vibrations.