Planar Motion Analysis for a Rotating Elastic Ball in Collison

It is generally well known that the motion of rotating elastic body in collision is complex but interesting. This is due to the deformation of the local contact part, the friction force acting on the contact surface and so on. It is difficult, however, to observe the state of affairs in collision because of instantaneous phenomenon. In this paper, two types of model for the motion of the rotaing elastic ball in planar collision are proposed. One is a simple model which consists of two particles with spring and damper. Another one consists of distributed particles in circumference, spring and dampers. An experiment is also carried out to compare with numerical results and verify their validity, using a high speed camera. The simple model represents some characteristics of the motion. Numerical results using another model agreed with experimental ones both qualitatively and quantitatively.