New balls please

Wimbledon begins on 2 July. Over the course of the Championships some 2,500 tennis balls will be used. To ensure balls have the required elasticity for play, they are routinely changed every six games. A simple and convenient way to test a ball court-side doesn't exist, so many balls are rejected unnecessarily. Until now. A team of mechanical engineering students at the University of Nottingham has developed a portable impact tester to accurately gauge the rebound of a tennis ball. The prototype is affordable, lightweight, can test a ball every 20 seconds and is designed to minimise waste.