RIGID BODIES COLLISIONS

We consider a point moving with respect to a rigid body. The system ma de up of these two elements is deformable since the distance of the po int and the body changes. This basic idea leads us to define strain ra tes and interior forces. The latter are percussions related to collisi ons and forces related to smooth evolutions. They are defined by their virtual work. The equations of motion are derived from the principle of virtual work. The constitutive laws for the interior percussions ar e the other equations which describe the evolution of the system when collisions occur between the point and the body. Examples illustrate t he ability of the theory to analyse practical situations, for instance multiple collisions.