Tennis ball impacts on synthetic turf

A pilot study has been carried out to look at the mechanics of tennis ball impacts on synthetic turf. A medium-paced forehand groundstroke was studied using high speed video and the velocities angles and spins recorded used to verify an aerodynamic model. The model was then used to predict the impact conditions for the medium paced forehand. Impacts were subsequently carried out on a synthetic turf system using unpressurised, low pressure and high pressure tennis balls. Impact velocities of 20 and 25 ms-1 were used at angles of 20 and 25° to the horizontal surface. It was found that unpressurised ball rebound 4% faster and at 10% lower angles than the high pressure ball. It was deduced that this was due to the small deformation of the unpressurised ball during impact causing it to slip throughout. The frictional forces were thus lower causing the ball to rebound faster.