Experimental validation of a tennis ball finite-element model

An explicit finite-element (FE) model of a pressurised tennis ball, consisting of an airbag, rubber core and felt cover, was produced in Ansys/LS-DYNA. The model was validated by comparing FE simulations of rubber cores and tennis balls, impacting on a rigid surface with experimental data. The laboratory investigation was undertaken by firing the balls and cores with an air cannon on to a force plate, at a range of velocities between 5 and 30 m.s-1. Values of force and contact times were obtained from the force plate data whilst the inbound and rebound velocities were recorded using a set of light gates. A Phantom high-speed video camera recording 6000fps was used to capture a number of impacts; this footage was then used to calculate the deformation of the balls and cores. The FE simulations were in good agreement with the experimental data for the range of impact speeds tested.