Measurements and linearized models for golf ball bounce

TL;DR

This study conducts extensive experiments on golf ball bounces, analyzing velocity and spin data to evaluate and improve models of golf ball rebound behavior on different turf surfaces.

Contribution

It provides a comprehensive dataset of golf ball bounces, compares experimental results with existing models, and introduces a non-physical piecewise model for better data fit.

Findings

Data shows balls often lift off slipping after bounce.

Existing models fit data poorly, especially for rolling cases.

A new piecewise model improves fit to experimental data.

Abstract

A detailed set of experiments are described that capture over a 1000 different instances of the bounce of a golf ball. Video analysis is used to capture velocity and spin immediately prior to and subsequent to each bounce for a wide variety of landing conditions. Data are presented from two different turfs; one artificial and one from a typical tee. Measurement errors and repeatability are analysed. The data are compared to predictions from models of rigid bounce with friction, including Penner's modification to account for elasto-plasticity. Coefficients of restitution and friction, and Penner's effective contact angle are fit from the data. A better fit to the data is found using a non-physical piecewise-affine landing to lift-off relationship, which distinguishes between cases that bounce in pure slip from those that undergo rolling. Nevertheless, even balls that undergo rolling are typically found to lift off slipping, having undergone spin reversal. The findings suggest that further effort needs to be spent on finding simple physics-based models of golf-ball bounce.