Inelastic ball-plane impact: An accurate way to measure the normal restitution coefficient

The authors describe a setup to measure accurately the normal restitution coefficient between a quasiresonant ball and a plane. It uses the fact that the trajectory of a single ball in a cylindrical box with a vibrating wall reduces rapidly to a merely periodic one dimensional dynamics, with little rotation. The ball speed is measured accurately from the time series of impacts. It is also used to study and calibrate a sphere-plane impact sensor. This sensor allows to determine the collision time at a microsecond accuracy and the maximum force applied. The collision is found to obey the Hertz law. (c) 2006 American Institute of Physics.