This is a section intended to collect together articles and data associated with the physical properties of croquet equipment and dynamics of balls. In addition any formulae and recipes will arrive here.
- Ball Properties
- Contact Times etc.
- Lawn Speeds
- Ranking Calculations
- Literature References
- Game Analysis
- Associated Material
Submissions are invited to this page - contact the webmaster.
What is presented here are reports by the authors, unless stated otherwise
they are not endorsed by any of the croquet bodies.
Ball Properties
Why aiming at the mid-point of the final resting places of the balls in a croquet stroke is only an approximation. A simple illustration of one of the issues. |
Mar 2010 |
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Nick shows that neither aiming at half the angle nor at the mid point between the final resting points of the balls is correct in most instances. For a take-off his conclusion is that you can hit much more into the croqueted ball. Nick Furse, UK |
Nov 2009 |
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Don has analysed the high speed video taken in 2006 by Bill Arliss and his team of croquet strokes. For 38 clips (available on the WCF website) he has measured velocities, ball spin, elevation, etc. He draws a number of significant conclusions which will support future analysis. He also presents the background theory in convenient appendices. These cover simple collisions without friction, spin imparted on balls during striking due to friction, spin due to the angle of the mallet face and the equations governing the onset of roll due to friction. Don Gugan, UK |
Mar 2009 |
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The properties of hoops are listed in a number of places and this document attempts to bring the specifications together. |
Feb 2009 |
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The Effect of Hoop Upright Diameter on the Acceptance Angle of a Hoop |
How to calculate the acceptance angle of a hoop. |
Feb 2009 |
Demonstration of determining the bias of a croquet ball will a bag of salt and lump of Blu-tack. |
Nov 208 |
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With the proposed changes in the Laws, this article discusses where to place a ball which has collided with a stationary one. |
Jan 2008 |
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Initial measurements of the surface temperature of croquet balls left
in the sun. |
June 2005 |
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Experiments on the Game of Croquet;
Bouncing and Rolling |
Experiments on the bounce characteristics of croquet balls and the
analytical treatment of the transition from sliding to rolling. Includes
a valuable appendix on lawn speed considering friction and the development
of spin. |
June 2002 |
Analysis of mallet head inertia |
Feb 2001 |
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What should be included in a croquet balls specification, plus an
appendix summarising standard properties. |
2000 |
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A table of croquet ball types and the dates when they were available. |
2000 |
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Predictions of mallets and ball velocities. |
Mar 2000 |
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Partition of the energy of rotation and kinetic energy. |
Mar 1999 |
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Considerations and methods when measuring croquet ball bounce. |
Oct 1998 |
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Using a ball-hitting rig RLM presents results and comments on different
croquet strokes and ball types, and the Roquet Shot. |
<1998 |
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Measurements of bias using billiard tables and floatation. |
<1998 |
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The effects of temperature and the construction of the ball bounce
test rig are discussed also the effect of milling and paint thickness. |
Aug 1993 |
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The rebound heights of different manufacturers' balls measured as
a function of temperature (extract from letter). |
Nov 1989 |
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Comparison of ball bounce and mass measurements made in South Africa
and England. |
Sep 1989 |
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Measurements of size, mass and bounce of one type of Barlow balls |
Aug 1989 |
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Championship Ball Specification for World Croquet Federation |
The size, mass and bounce variations of a set of the older Barlow
croquet balls. |
Jun 1989 |
Moulding, physical properties; size, mass. Conclusion. |
Aug 1988 |
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Richard Le Maitre, South Africa |
Mar 1988 |
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Comparison of Jaques and early Barlow XTs. |
Dec 1986 |
Contact Times etc.
Hitting a ball off-centre induces a rotation of the mallet head and a slewing of the ball from the direction of swing. This is emphasised in mallets without peripheral (end face) weighting. |
2007 |
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An anlysis of the processes of single stroke impacts, and impacts
when there is a nearby ball |
2004 |
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Electrical timing to resolve contact times. |
1998 |
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Ball-mallet impacts observed using carbon paper. |
1998 |
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Further carbon paper tests. |
2000 |
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Electrical conduction tests. |
2000 |
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A discussion of the methodology for testing how easy different
types of hoops are to run. |
2004 |
Lawn Speeds
| How to Determine Lawn Speed During a Game | Louis Nel offers a simple method to replace interpolation for measuring the Lawn Speed in Plummers. Louis Nel, Canada |
March 2008 |
Samir Patel suggest that a lawn speed of 10 Plummers is normal and >10 is desirable for top level events. |
June 2007 |
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Comparisons are made between the Lambert and Plummer systems of lawn speed measurement. |
April 2007 |
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A simple method for measuring the speed of a lawn using a plank, a ball, a tape measure and a hoop. |
June 2005 |
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A brief explanation about lawn speeds is accompanied by a simple derivation
and experimental measurements. |
April 2004 |
Ranking Calculations
Louis Nel analyses the current ranking system in use by the Croqyet Association and proposes a modification. Louis Nel, Canada |
2009 |
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Louis Nel gives a simple primer and background to his Bayesian Ranking System. (Internet Explorer recommended). |
2008 |
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Louis Nel advocates a new ranking system which considers the mean level
of play and its certainty. |
2006 |
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Louis Nel gives the probability that someone will win a game based on the difference in the grades of the two players. |
2005 |
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Louis Nel models how the positions of players in the Rankings change even if everyone's ability to win remains constant. |
2005 |
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Comparisions of Handicap and Grade for Players from Different Countries |
2004 |
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Web site dealing with the basics of the chess rating systems including the Elo system on which the croquet rankings are based |
2004 |
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A non-mathematical explanation of the how the Croquet Grading System
works. |
2004 |
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Comparisions of Handicap and Grade for Players from Different Countries |
2002 |
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How the calculations are performed |
2001 |
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No corellation was found betweeen American Handicaps and Associattion
Handicaps. |
2000 |
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Note on the assignment of the class factor etc. for rankings. |
1999 |
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The mathematics behind the current grading system. |
1998 |
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The mechanics of the ranking system. |
1993 |
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Comments on the mathematics involved in the ranking system. |
1988 |
Croquet in Scientific Literature
American Journal of Physics, Vol. 68, No. 10, pp. 920-924. |
2000 |
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David R. Appleton, The Statistician Vol. 44, #4, pp.529-538, (1995) |
1995 |
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Design of Croquet Mallets etc. |
Project Report, University Central Lancs, UK. (?) |
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A Survey of Croquet Injuries |
David R. Appleton, Journal of the Royal Society of Medicine, Vol. 90, #4, pp.218-220, (1997) |
1997 |
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Development of a Croquet Ball |
Project Report, Imperial College, UK. Supervised. Prof. B.G.Neal, (1981) |
1981 |
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Engineering, pp.861-863, (29 June 1962) |
1962 |
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Game Analysis
Louis Nel proposes that promotion out of the blocks proceed globally
rather than block-by-block |
2007 |
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Don Gugan investigates whether there is any evidence of a 'home advantage'. |
2004 |
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Louis Nel |
2003 |
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How to calculate winning probabilities for knock-out tournaments |
Louis Nel |
2000 |
Associated Material
- Article on Lawn Bowls manufacture & testing, Peter Clare
- Performance standard for artificial flat green bowls surfaces, WBB 1995
- The Physics of Ball Games, C.B. Daish, 1972
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