RIGID BODIES COLLISIONS

We consider a point moving with respect to a rigid body. The system made up of these two elements is deformable since the distance of the point and the body changes. This basic idea leads us to define strain rates and interior forces. The latter are percussions related to collisions 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 are the other equations which describe the evolution of the system when collisions occur between the point and the body. Examples illustrate the ability of the theory to analyse practical situations, for instance multiple collisions.