ABSTRACT
One-dimensional models of a golf ball are useful in modelling near-normal (90°) impact. The model described here has two masses connected by a non-linear spring in parallel with a non-linear damper. Behaviour of this system in collision with an infinite rigid mass is compared with the results of tests involving real golf balls. Values of the four unknown constants are found by fitting the model results, over a range of impact speeds from zero to 50 m/s, to the coefficient of restitution (COR) and duration of contact (T) found in the tests.
The simplest form of the model (Model 1) is a good fit to experiment for T over the whole range of impact speed, but for COR only at high speed (above 20 m/s). However, when used with a similar model of a flexible faced club, the simple model predicts the COR of the club/ball combination, determined by direct testing, quite well and as such is a useful screening tool.
More complicated Models 2 and 3 fit the rigid target COR’s better at low speed than does Model 1, but have other disadvantages and are no better than Model 1 for high-speed impact with flexible faced clubs.
