Modelling impacts of sports surfaces

A normal impact model was developed to describe the dynamic behaviour of a rigid mass during impact with a sports surface. It was designed empirically to satisfy a set of four criteria, know to occur before, during and after impact. Using four pre-determined coefficients, the model is capable of predicting the change acceleration, velocity and displacement of the rigid mass during impact. The model was evaluated using acceleration data from impact hammer tests on two designs of artificial cricket pitch. The model was then developed further to describe the oblique impact of a cricket ball and evaluated using displacement data taken from high speed video footage of balls impacting on a natural turf pitch. In both cases, the results from the model were found to be in good agreement with the experimental data. A method of sports surface material classification was suggested, using the empirical coefficient of the model to compare the performance of each surface system.