Measurement of the speed and bounce of tennis courts

Abstract

Tennis is played on a wide variety of court surfaces that can be classified as fast, medium, or slow, according to the coefficient of sliding friction between the ball and the court. The vertical bounce properties depend on the coefficient of restitution. Both coefficients can be measured by using a video camera to film the bounce of a ball incident at a low angle on the court. It is easier to analyse the data when filming at high film-rates, around 200 frames per second (fps) or more, but reliable data can also be obtained when filming at the standard 25 or 30 fps rate used in most video cameras. In this paper we describe results obtained at both 25 fps and 500 fps and consider some of the physics issues involved in interpreting the data.

Keywords:

• Tennis
• court speed
• coefficient of friction
• coefficient of restitution
• measurement

Acknowledgements

I would like to thank Steve Lock from Tennis Australia and Jamie Capel–Davies from the ITF for sharing with me the 500 fps data they obtained in London and which is shown in Figures 3 and 4.