FRICTIONAL TORQUE AND COMPLIANCE IN COLLINEAR ELASTIC COLLISIONS

Principles of dynamics together with a statical theory for deformation in the contact region are used to analyse changes in frictional torqu e and spin during collinear impact between rough elastic spheres. Spin is the normal component of relative angular velocity between two coll iding bodies. Changes in spin are due to frictional torque of shear tr actions acting on the contact patch during collision; the Hertz theory of local elastic deformation is used to calculate the finite radius o f contact that generates torque. In the contact patch, the distributio n of shear traction depends on tangential compliance and relative rota tion.