# Science and Golf II: Proceedings of the 1994 World Scientific Congress of Golf

By A. J. Cochran; M. R. Farrally | Go to book overview

64

Golf ball impacts, greens and the golfer

S.J. Haake

University of Sheffield, UK

Abstract

This paper gives a brief overview of the results of a 3 year project to study the relationship between the characteristics of golf greens and the impact of golf shots on them. To this end, an apparatus was developed to project spinning golf balls directly onto golf greens with the resulting impacts recorded on film. The apparatus was used on eighteen golf courses resulting in 721 useful photographs of impacts. Two types of green emerged from analysis of the photographs; on the first, the ball tended to rebound with topspin, while on the second, the ball retained backspin if the initial backspin was large enough.

Eleven tests were used to determine the characteristics of greens and the relationships between the characteristics were linked to the impact study. It was found that it was easier to retain backspin on the rebounding ball on a green that was freely drained and had a low amount of Poa annua in its sward.

A mathematical model was developed to simulate the impact of the ball with the turf. The model gave sensible results for oblique impacts with backspin.

Keywords: Golf, Impact, Turf, Playing Quality.

1 Introduction

This project was carried out at the Sports Turf Research Institute in conjunction with the University of Aston in Birmingham. Manufacturers of golf balls have carried out many tests to study the behaviour of the ball on impacting with the golf club face. There has also been much work done on the aerodynamics of the golf ball (Bearman and Harvey 1976). There is little information, however, on what is a fundamental part of the game of golf-the impact of the ball with the green. With a better understanding of the process of impact it may be possible to define a given turf using a few easily measurable quantities and hence to predict how a golf green will play. These tests could then be used to aid the maintenance and construction of golf greens.

2 Apparatus

2.1 Recording golf ball impacts

The apparatus has been described in detail by Haake (1991a). Briefly it comprises a modified baseball practice machine to project the golf balls directly at the green and a light tight tent covering the impact zone to enable stroboscopic photographs of the impact to be recorded. The complete set of apparatus is shown in Figure 1. The projection apparatus has two identical wheels with pneumatic tyres with their axes parallel. The wheels rotate in opposite directions and when a ball rolls down the chute it enters the gap between the wheels. It is then gripped and fired out of the other side. The speeds of the two motors

Science and Golf II: Proceedings of the World Scientific Congress of Golf. Edited by A.J. Cochran and M.R. Farrally. Published in 1994 by E & FN Spon, London. ISBN 0 419 18790 1

-431-

If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items
Notes

#### Cited page

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

(Einhorn 25)

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

#### Cited page

Science and Golf II: Proceedings of the 1994 World Scientific Congress of Golf

Settings

#### Settings

Typeface
Text size Reset View mode
Search within

Look up

#### Look up a word

• Dictionary
• Thesaurus
Please submit a word or phrase above.

Why can't I print more than one page at a time?

Help
Full screen
Items saved from this book
• Bookmarks
• Highlights & Notes
• Citations
/ 643

### How to highlight and cite specific passages

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select, and you’ll see everything in between get selected.
3. You’ll then get a menu of options like creating a highlight or a citation from that passage of text.

## Cited passage

Style
Citations are available only to our active members.
Buy instant access to cite pages or passages in MLA 8, MLA 7, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

## Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.