ArticlePDF Available

The 2010 Regulations on Golf Club Groove Design: Impact on Ball Flight Characteristics during a Controlled Shot

Authors:

Abstract and Figures

The purpose of this study was to investigate the difference in the amount of spin that can be generated during a controlled golf shot, as a result of the 2010 rule change regarding restrictions applied to the design of the grooves on the clubface implemented by the United States Golf Association and the Royal & Ancient Golf Club. Ten experienced golfers (mean ± SD; age, 23.0 ± 0.67 yr; playing experience, 13.2 ± 1.6 yr; handicap, 1.6 ± 1.4) were required to play a total of 120 shots inside a state of the art golf simulator with 3 clubs consisting of “old” pre 2010 U-groove design and “new” post 2010 V-groove design. With the U and V grooved clubs, participants played 10 shots from a fairway mat and 10 shots from a rough mat using a 9 iron, PW and SW. Backspin (RPM) and, as a measure of accuracy, distance landed from the pin (yds) were recorded. Compared with the U-grooves, the newer V-groove design imparted significantly less backspin from both the fairway and rough surfaces (p < .05), additionally, shots with all clubs were consistently further away from the pin (p < .05). The newer groove design does not enable players to impart as much backspin on the ball as they previously could and our data suggest that the recent change in golf club design might therefore reward driving accuracy. The purpose of this study was to investigate the difference in the amount of spin that can be generated during a controlled golf shot, as a result of the 2010 rule change regarding restrictions applied to the design of the grooves on the clubface implemented by the United States Golf Association and the Royal & Ancient Golf Club. Ten experienced golfers (mean ± SD; age, 23.0 ± 0.67 yr; playing experience, 13.2 ± 1.6 yr; handicap, 1.6 ± 1.4) were required to play a total of 120 shots inside a state of the art golf simulator with 3 clubs consisting of “old” pre 2010 U-groove design and “new” post 2010 V-groove design. With the U and V grooved clubs, participants played 10 shots from a fairway mat and 10 shots from a rough mat using a 9 iron, PW and SW. Backspin (RPM) and, as a measure of accuracy, distance landed from the pin (yds) were recorded. Compared with the U-grooves, the newer V-groove design imparted significantly less backspin from both the fairway and rough surfaces (p < .05), additionally, shots with all clubs were consistently further away from the pin (p < .05). The newer groove design does not enable players to impart as much backspin on the ball as they previously could and our data suggest that the recent change in golf club design might therefore reward driving accuracy.
Content may be subject to copyright.
54
International Journal of Golf Science, 2013, 2, 54-64
© 2013 Human Kinetics, Inc. Official Journal of WSCG
www.IJGS-Journal.com
ARTICLE
The 2010 Regulations on Golf Club
Groove Design: Impact on Ball Flight
Characteristics During a Controlled Shot
Paul Burnham, Mick Wilkinson, and Stuart Goodall
Northumbria University
The purpose of this study was to investigate the difference in the amount of spin
that can be generated during a controlled golf shot, as a result of the 2010 rule
change regarding restrictions applied to the design of the grooves on the clubface
implemented by the United States Golf Association and the Royal & Ancient Golf
Club. Ten experienced golfers (mean ± SD; age, 23.0 ± 0.67 yr; playing experience,
13.2 ± 1.6 yr; handicap, 1.6 ± 1.4) were required to play a total of 120 shots inside
a state of the art golf simulator with 3 clubs consisting of “old” pre 2010 U-groove
design and “new” post 2010 V-groove design. With the U and V grooved clubs,
participants played 10 shots from a fairway mat and 10 shots from a rough mat
using a 9 iron, PW and SW. Backspin (RPM) and, as a measure of accuracy, distance
landed from the pin (yds) were recorded. Compared with the U-grooves, the newer
V-groove design imparted signicantly less backspin from both the fairway and
rough surfaces (p < .05), additionally, shots with all clubs were consistently further
away from the pin (p < .05). The newer groove design does not enable players to
impart as much backspin on the ball as they previously could and our data suggest
that the recent change in golf club design might therefore reward driving accuracy.
Keywords: accuracy, backspin, clubface, grooves
On January 1st, 2010 the United States Golf Association (USGA), in associa-
tion with the Royal & Ancient Golf Club (R&A), implemented changes to the way
in which golf club grooves are designed. The intention of the rule change was to
remove a player’s ability to generate as much spin out of the rough as can be created
on the fairway. This was achieved by changing the size and sharpness of the previ-
ous large, deep and sharp edged U-grooves into shallower, smaller and round-edged
V-grooves (USGA & R&A, 2006). It was anticipated that this change to the grooves
would produce less spin in the rough, and as a result, not allow players to achieve
as good a shot as they might have had they landed on the fairway. Ofcials hoped
this would promote accuracy from the tee and be a form of punishment for those
who do not nd fairways. Thus, the intention of this rule change was to reward
players for driving accuracy (Acimovic & Fearing, 2011), however, the impact of
this change on golf ball ight characteristics is not yet known.
The authors are with the Faculty of Health & Life Sciences, Northumbria University, Newcastle, UK.
Golf Club Groove Design and Performance 55
Being able to impart spin on a golf ball from a fairway position is a key
requirement to land shots close to the hole, ultimately increasing the chance of
success. Subsequently, it is important to know how much of a reduction in spin, if
any at all, there is between the old and new groove designs. The rule change does
not just apply to elite tour professionals. The USGA and R&A are enforcing this
change throughout the game so it will eventually apply to golfers at every level.
The rule was rst introduced into the professional game in 2010, changes will apply
to all amateur professionals in 2014 and subsequently will apply to all remaining
golfers by 2024 (R&A, 2010). Thus, it is essential to understand how this change
might impact the professional game but also how it might affect golf in the future.
Due to the timing of this rule change, there is currently a paucity of peer-reviewed
literature on the topic. Opinions however, have been expressed extensively in other
forms of media, particularly online.
We currently have an understanding of how surface roughness, ball hardiness
and loft angle of a club affect the ability to produce backspin (Farrally et al., 2003).
There are, however, elements within this process that are not fully understood and
have not yet been tested to any great extent. Surprisingly, very limited research into
the full functionality that grooves provide during golf shots and the role grooves play
in contributing toward the production of backspin have been overlooked in previous
studies (Cochran & Farrally, 1994; McCloy, Wallace, & Otto, 2006). The “old” pre
2010 U-grooves are larger and deeper in size compared with the “new” V design.
U-grooves have sharp right angle edges and the greater overall volume of the groove
lters debris and water away from the surface of the club very efciently allowing
for a clean, clear contact with the ball and the clubface. This allows the sharp edges
of the grooves to grip the ball causing it to roll and generate a large amount of back-
spin, this make them very effective when playing a shot from the fairway or rough.
The “new” post 2010 V -grooves are between 40–50% smaller in volume than the
previously used U-grooves; the edges are rounded lessening their ability to grip the
ball at contact thereby reducing the spin imparted. The depth of groove has also been
reduced and is most commonly in a V shape, although square designs with curved
edges are available (Figure 1). Sauerhaft (2010) has explained that the decrease in
volume makes the new grooves less efcient at ltering away debris and moisture
in the rough, leaving behind water and debris on the clubface at ball strike resulting
in less spin. However, this is yet to be elucidated in a peer reviewed manner.
To our knowledge, peer reviewed literature is not available specically regard-
ing the rule change and golf shot performance. Thus, the aim of the current study was
to assess the effect of the change in groove design on the backspin and accuracy of
controlled golf shots played by experienced, low handicap golfers from the fairway
and rough. It was hypothesized that shots taken with the post 2010 conforming
V-grooves would reduce backspin and accuracy compared with shots played with
the pre 2010 nonconforming U-grooves from both the fairway and rough.
Methods
Participants
Ten male golfers volunteered to participate in the study (mean ± SD, age, 23.0 ±
0.67 yr; playing experience, 13.2 ± 1.6 yr; handicap, 1.6 ± 1.4). All participants
56
Figure 1 — Pre and Post-2010 groove specications.
Golf Club Groove Design and Performance 57
gave written, informed consent before the commencement of the study. Upon
arrival to the laboratory, experimental procedures, associated risks and potential
benets of participation were explained. The study was approved by Northumbria
University’s School of Life Science Ethics Committee.
Experimental Design
The testing was carried out using an indoor golf simulator (Gold Simulator, Sports
Coach System Ltd, Surrey, UK). Each testing session lasted 1–2 hours and before
testing began, each participant was required to perform a warm up consisting of
stretching, mobility exercises, rotation and 5 practice shots with each club. Each
participant played 20 shots with 6 clubs (9 iron, PW and SW of “old” and “new”
groove conformation); 10 shots were played from a fairway mat and 10 shots
were played from a mat simulating rough grass. In total, 60 shots were played
with the U-groove clubs and 60 shots were played with the V-groove clubs, thus,
participants completed 120 shots. The order of the conformation and the club used
was randomized and the same hole and pin position was set for each participant
(Celtic Manor 18th). Conditions were set to ne; there was no wind and each shot
was played at a set distance from the hole (9 iron, 120 yds; PW, 100 yds and SW,
80 yds). Participants were instructed to play the most accurate shot they could
to land the ball as close to the hole as possible. From each shot, the amount of
backspin (RPM) and, as a measure of accuracy, the distance landed from the pin
(yds) was recorded.
Golf Club Design and Equipment. Specically, dimensions of irons conform-
ing to the rule change are: the width, spacing and cross-section of the grooves
must be consistent throughout the impact area; the width of each groove must
not exceed 0.035 inches (0.9 mm) using the 30 degree method of measurement
on le with The R&A; the distance between edges of adjacent grooves must not
be less than three times the width of the grooves, and not less than 0.075 inches
(1.905 mm); the depth of each groove must not exceed 0.020 inches (0.508 mm);
for clubs other than driving clubs, the cross-section of the groove divided by
the groove width and distance between grooves must not exceed 0.0030 square
inches per inch (0.0762 mm2/mm); grooves must not have sharp edges or raised
lips; for clubs with a loft angle greater than or equal to 25 degrees, groove edges
must be substantially in the form of a round edge, having an effective radius
which is not less than 0.010 inches (0.254 mm), and not greater than 0.020 inches
(0.508 mm); deviations in effective radius within 0.001 inches (0.0254 mm) are
permissible (Figure 1). The nonconforming U-groove clubs used were 2004
Callaway Big Bertha (Callaway Golf, CA, USA) and the conforming V-groove
clubs used were 2010 Cleveland CG-16 (Cleveland Golf, CA, USA). Brand new
sets of the same golf ball (Z-Star Srixon, Cleveland Golf, CA, USA) were used
for each participant.
Golf Simulator. The simulator and associated software (Gold Simulator, Sports
Coach System Ltd, Surrey, UK) consisted of a booth, a high spec computer and
projector system. This golf simulator was used as it allows for control of many
variables that have an impact on the generation of spin (i.e., wind, rain, wet and dry
greens). This allowed for data to be collected in a valid and repeatable environment.
58 Burnham, Wilkinson, and Goodall
The golf simulator contained two high speed cameras set to track the ball and
transmit data to the receiving computer. A side camera monitored the launch
angle and speed of the ball, while the camera located above monitored direction
and spin. The two high speed cameras worked simultaneously at separate 90°
angles to create a 3D model of ball ight. Each camera used high quality CMOS
sensors that were processed at 60 Hz. Images were produced on screen in front
of the golfer via an XGA projector delivering 4500 lumens with a throw distance
of between 1.5 m and 7 m and native 1024 × 768 display. The overhead camera
tracked the ball from impact and informed the software that the ball had been hit.
At the same time exact data relating to the horizontal launch angle, club speed,
ball spin, swing path and face angle relative to the target line were determined. The
lateral camera constantly tracked the golf ball from impact as it traveled toward
the screen enabling accurate measurement of the vertical launch angle, ball speed
and spin, determining the carry of the ball through the air.
Statistics
Data are presented as means ± SD within the text and displayed as means ± SE in
the gures. Following verication of underlying assumptions, 2 × 2 ANOVA with
repeated measures on groove type and surface was used to test for within group
differences in spin rate and shot accuracy between pre 2010 U-grooves and post
2010 V-grooves, between fairway and rough and for interaction effects between
groove type and surface. Signicant main effects were further examined using
Tukey simultaneous 95% condence intervals to provide a plausible range for the
true population mean differences. Data analysis was performed in Minitab (v16.2.2,
Minitab Ltd, Coventry, UK) and signicance was set at p < .05.
Results
Nine Iron Spin Rates
There were signicant effects of groove (F1 = 195.65, p < .01) and surface (F1 =
311.66, p < .01) on spin rate and a signicant groove by surface interaction (F1
= 4.42, p = .04). Spin rates were higher from the fairway than the rough for both
U-groove (9027 ± 130 vs. 8084 ± 222 RPM, 95% CI 757–1127 RPM) and V-groove
(8259 ± 203 vs. 7518 ± 146 RPM, 95% CI 557–926 RPM) clubs. Spin rates were
higher with the U-groove than V-groove clubs from the fairway (95% CI 582–952
RPM) and from the rough (95% CI 382–751 RPM). The loss of spin from fairway
to rough did not differ between U-groove and V-groove clubs (95% CI 10 to −359
RPM) (Figure 2).
Nine Iron Accuracy
Both groove type (F1 = 18.99, p < .01) and playing surface (F1 = 8.64, p < .01)
affected nine iron shot accuracy but there was no groove by surface interaction
(F1 = 1.87, p = .183). Regardless of playing surface, shots with the U-groove club
were nearer to the target than shots taken with the V-Groove club (95% CI −1.26
to −0.45 yds). Regardless of groove type, shots from the rough landed further from
the target than shots from fairway (95% CI 0.17–0.98 yds) (Table 1).
59
Figure 2 — The amount of backspin produced with shots taken from the fairway and rough
using a 9 iron (A), PW (B) and SW (C) with the “old” U-groove ( ) and the “new” V-groove
() congurations. $ = p < .05 fairway vs. rough; * = p < .05 U-groove vs. V-groove.
60 Burnham, Wilkinson, and Goodall
Pitching Wedge Spin Rates
Groove type (F1 = 241.84, p < .01) and playing surface (F1 = 296.07, p < .01) had a
signicant effect on spin rate and there was a signicant groove by surface interac-
tion (F1 = 6.59, p = .02). Higher spin rates were evident from the fairway than from
the rough for U-groove (9612 ± 85 vs. 9015 ± 188 RPM, 95% CI 438–754 RPM)
and V-groove clubs (9082 ± 138 vs. 8277 ± 108 RPM, 95% CI 648–963 RPM). As
with the nine iron, spin imparted to shots was higher with U-groove than V-groove
clubs both from the fairway (95% CI 371–686 RPM) and the rough (95% CI
580–896 RPM). There was no difference between U-groove and V-groove clubs in
the amount of spin lost from fairway to rough (95% CI 90 to -225 RPM) (Figure 2).
Pitching Wedge Accuracy
There were independent effects of groove type (F1 = 39.02, p < .01) and playing
surface (F1 = 34.10, p < .01) on shot accuracy, but no interaction effect (F1 = 0.02,
p = .89). Shots played with the U-groove club landed closer to the target than those
played with the V-groove club regardless of the playing surface (95% CI −1.22 to
−0.62 yds). Shots played from the rough landed further from the target than shots
played from the fairway regardless of groove conguration (95% CI 0.56–1.16
yds) (Table 1).
Sand Wedge Spin Rates
There were signicant and independent effects of groove (F1 = 877.18, p < .01)
and playing surface (F1 = 872.38, p < .01) on sand wedge spin rates, but no inter-
action between groove type and playing surface (F1 = 0.27, p = .60). Higher spin
was imparted by U-groove than V-groove clubs for both playing surfaces (95%
CI 853–980 RPM) and spin was lower from the rough than the fairway for both
groove congurations (95% CI −978 to −851 RPM) (Figure 2).
Table 1 Average Distance (yds) Away From the
Hole with “Old” U-Groove and “New” V-Groove
Configured Clubs.
U-Groove V-Groove
Fairway
9 iron 11.8 ± 1.1 12.9 ± 1.1
PW 10.8 ± 1.0 11.8 ± 1.0
SW 9.4 ± 0.7 11.0 ± 0.8
Rough
9 iron 12.6 ± 0.5 13.2 ± 1.5
PW 11.7 ± 0.8 12.6 ± 1.5
SW 10.6 ± 0.9 11.6 ± 0.8
Values are means ± SD for 10 participants.
Golf Club Groove Design and Performance 61
Sand Wedge Accuracy
Similarly to the nine iron and pitching wedge, there were independent effects of
groove type (F1 = 42.19, p < .01) and playing surface (F1 = 18.04, p < .01) on the
accuracy of shots played with the sand wedge, but no groove by playing surface
interaction effect (F1 = 1.96, p = .17). Again, the U-grooves resulted in shots less
far from the target than the V-grooves regardless of playing surface (95% CI −1.71
to −0.89 yds) and shots from the rough landed further from the target than shots
from the fairway regardless of groove type (95% CI 0.43–1.26 yds) (Table 1).
Discussion
The aim of the current study was to address the effect of the newly introduced
regulations in golf club groove design enforced by the USGA and R&A in 2010.
We examined whether the “new” post 2010 V-groove design reduces the amount
of spin and accuracy during a controlled golf shot compared with the “old” pre
2010 U-groove design. Compared with the U-grooves, the newer V-groove design
imparted signicantly less backspin on shots both from the fairway and rough;
additionally, shots with all 3 clubs were consistently less accurate. The newer
groove design does not enable players to obtain as much control of the ball as they
previously could, such that the recent regulatory change in golf club design might
reward driving accuracy.
Peer reviewed work on this topic is sparse which makes comparison with
previous literature difcult. The USGA and R&A, however, have released details
of “in house” testing carried out using the U- and V-grooved clubs (USGA &
R&A, 2006, 2007). Their ndings correspond to our data, in that a reduction of
backspin in shots played from the rough with V-grooved irons was reported. Our
data add to these previous results by demonstrating a reduction in backspin with
shots played from the fairway as well as the rough and examining the effect of
this spin reduction on shot outcome. Another previous investigation that focused
solely on the issue of the ban, found that the change in regulation did not produce
any signicant difference in terms of difculty hitting from the rough (Acimovic &
Fearing, 2011). Although our data oppose that of Acimovic & Fearing (2011) the
research design adopted differs substantially. Acimovic & Fearing (2011) did not
carry out any practical testing of the equipment; they assessed data from the PGA
Tour over a 30-year period and specically focused on two elements, has the rule
change affected players driving accuracy and their ranking in the money list, and,
have players visually changed their styles when in the rough. Whereas the current
study obtained quantitative data and assessed the impact of the rule change on
amateur professional’s ability to generate spin. Collectively, our data oppose that
of Acimovic & Fearing (2011); shots played from the rough with the new V-groove
clubs were more difcult to control and less accurate.
Previous work by Cochran & Stobbs (1968) suggesting that clubface sur-
face roughness does not inuence backspin seems contrary to our data. Figure 2
demonstrates that even when clubs of the same loft are used, the amount of spin
differs as a result of the amount of grip and friction caused which is in line with
previous research (Chou, Liang, Yang, & Gobush, 1994). However, research exists
62 Burnham, Wilkinson, and Goodall
that would suggest our ndings are a direct result of ball softness (Gobush, 1996;
Monk, Davis, Otto, & Strangwood, 2005). These data would suggest that it is the
softness of the golf ball that produces the difference in spin rate. However, soft
shelled golf balls were not specically used in the current study; a popular mid-
range golf ball was used and, despite the precise composition not being known,
the balls are not regarded as “soft”.
To understand what happens upon impact of the clubface and golf ball, one
must appreciate that what determines a ball’s fate happens within half a millisecond.
Thus, what happens in this small time frame is imperative to understanding how
the clubface and ball interact (Cochran & Farrally, 1994). Johnson and Lieberman
(1996) examined this interaction and found that when a golf ball makes contact
with the club head, two things happen: sliding and rolling. The sliding and roll-
ing occur due to friction; as the ball contacts the club it begins to climb up the
clubface, such that the surface of the clubface determines whether the ball begins
to roll or slide up the clubface. A golf ball that rolls up the clubface develops
backspin; however, a golf ball that slides up the clubface drastically reduces the
backspin imparted. Therefore, the extent that the surface of the clubface promotes
rolling and prevents sliding, ultimately determines the generation of spin. This is
where the grooves on the clubface make their contribution to the generation of
spin (Johnson & Lieberman, 1996). Lieberman (1990) found that grooves do not
just provide a form of friction to encourage the ball to roll, they essentially work
like the tread on a tire. The grooves on a clubface are used to lter away water,
grass and other debris away from the clubface so a clean contact and ultimately
spin, can be imparted to the ball (Lieberman, 1990). Should water and debris not
be ltered away, but instead be left between the ball and clubface at impact, the
grooves will be prevented from gripping the ball, causing the ball to slide up the
clubface reducing the amount of spin.
In addition, to the surface of the clubface it is also important to understand the
aerodynamics of a spinning golf ball as it is launched into ight. Initially, with a
stationary ball, airow is slowed as it comes into contact with the front of a ball;
airow then increases as it moves around the ball and this increase in airow causes
low pressure (Smith, Beratlis, Balaras, Squires, & Tsunoda, 2010). Similarly, Smits
& Smith (1994) found that when a ball is spinning airow is slowed at the point of
contact; due to airow moving over the ball at a heightened pace compared with
when stationary, a much lower pressure is caused above the ball and the airow
underneath the ball is slower creating high pressure. That high pressure will force
the ball into the area of low pressure and lift is created (Bearman & Harvey, 1976).
However, a golf ball will only lift once the high and low pressures overcome the
weight of the ball; Aoki, Nakayama, Hayasida, Yamaguti & Sugiura (1999) identify
that this is where “Bernoulli’s Principle” becomes important. Bernoulli’s principle
states that spin rate and the pressure differential between the bottom and top of the
ball are positively correlated. Thus, if the spin rate is high enough, pressures will be
created that overcome the weight of the ball and lift will occur. This might, in part,
explain why accuracy was reduced when shots were taken with the new V-groove
clubs. The V-grooved clubs imparted a signicantly lower spin rate and ultimately
less lift; thereby a shallower trajectory and lack of backspin could not counteract
the forward momentum of the shot when landing on the green.
Golf Club Groove Design and Performance 63
There were a few unavoidable sources of error within this study. One of which
was being unable to use a real grass surface to play shots from, a synthetic fairway
and rough replacement mat had to be used which might limit the generalization of
the results. Upon analysis of our ndings and that of previous literature, it seems
that one of the key inuences upon backspin production is the skill level of the
player. Elite amateur golfers notice a reduction in spin from the grooves, whereas
elite professional golfers do not (Acimovic & Fearing, 2011; McFall, Todd &
Treme, 2012). The rule change may have failed to affect current elite professionals
due to their highly advanced skill level. In the future, the change may impact tour
professionals by enforcing driving accuracy up through the amateur levels. However,
there might be a way of combating this problem, it would seem that if the friction
between the ball and clubface is compromised particularly by the rounded edges,
players might be able to create more spin by using a softer golf ball to allow more
chance of gripping, but in addition to the longevity of the golf ball, a sacrice of
distance would also be apparent.
Conclusion
In conclusion, the “new” post 2010 V-groove clubs imparted signicantly less
backspin compared with the “old” pre 2010 U-groove clubs on shots taken from the
fairway and the rough. In addition, shots played with the V-grooved clubs landed
consistently further from the pin, indicating a reduction in accuracy. Thus, the recent
change in golf club design might reward accuracy from the tee.
References
Acimovic, J., & Fearing, D. (2011). A groovy kind of club: Examining the impact of new
grooves rules on the PGA Tour. MIT Sloan Sports Analytics Conference, 1(1), 1-8.
Aoki, K., Nakayama, Y., Hayasida, T., Yamaguti, N., & Sugiura, M. (1999). Flying Charac-
teristic and Flow Patterns on a Sphere with Dimples. In A.J. Cochran & M.J. Farrally
(Eds.), Science and Golf III (pp. 445–456). London: E & F N Spoon.
Bearman, P.W., & Harvey, J.K. (1976). Golf ball aerodynamics. Aeronautical Quarterly,
27(May), 112–122.
Chou, P.C., Liang, D., Yang, J., & Gobush, W.Cochran, A.J., & Farrally, M.J. (Eds.). (1994).
Contact forces, coefcient of restitution, and spin rate of golf ball impact. In A. J.
Cochran & M. J. Farrally (Eds.), Science and Golf II: Proceedings of the second world
scientic congress of golf (pp. 296 - 301). London: E & F N Spoon.
Cochran, A.J., & Farrally, M.R. (Eds.). (1994). Science and Golf II. London: E & FN Spon.
Cochran, A.J., & Stobbs, J. (Eds.). (1968). The Search for the Perfect Swing: An Account of
the Golf Society of Great Britain Scientic Study. Portsmouth: Heinemann.
Farrally, M.R., Cochran, A.J., Crews, D.J., Hurdzan, M.J., Price, R.J., Snow, J.T., . . .. (2003).
Golf science research at the beginning of the twenty-rst century. Journal of Sports
Sciences, 21(9), 753–765. PubMed doi:10.1080/0264041031000102123
Gobush, W. (1996). Friction coefcient of golf balls. Engineering of Sport, 12, 193–194.
Johnson, S.J., & Lieberman, B.B. (1996). Normal Impact Models for Golf Balls. Paper
presented at the Proceedings of the 1st International Conference on the Engineering
of Sport, Shefeld, UK.
Lieberman, B.B. (1990). The effect of impact conditions on golf ball spin rate. In A.J. Cochran
(Ed.), Science and Golf (pp. 225–230). London: E & F N Spoon.
64 Burnham, Wilkinson, and Goodall
McCloy, A.J., Wallace, E.S., & Otto, S.R. (2006). Iron golf club striking characteristics
for male elite golfers. The Engineering of Sport, 6, 353–358. doi:10.1007/978-0-387-
45951-6_63
McFall, T., Todd, A., & Treme, J. (2012). ‘Pandora’s groove: Analysing the effect of the
U- groove ban on PGA Tour golfers’ performances and strategies’. Applied Economics
Letters, 19, 763–768. doi:10.1080/13504851.2011.603684
Monk, S.A., Davis, C.L., Otto, S.R., & Strangwood, M. (2005). Material and surface effects
on the spin and launch angle generated from a wedge/ball interaction in golf. Sports
Engineering, 8, 3–11. doi:10.1007/BF02844127
R&A. (2010). Groove Guidance.
Sauerhaft, R. (2010). Tested: New Grooves vs. Old Grooves.
Smith, C.E., Beratlis, N., Balaras, E., Squires, K., & Tsunoda, M. (2010). Numerical
investigation of the ow over a golf ball in the subcritical and supercritical regimes.
International Journal of Heat and Fluid Flow, 31(3), 262–273. doi:10.1016/j.ijheat-
uidow.2010.01.002
Smits, A.J., & Smith, D.R.Cochran, A.J., & Farrally, M.J. (Eds.). (1994). A New Aerodynamic
Model of a Golf Ball in Flight. In A. J. Cochran & M. J. Farrally (Eds.), Science and
Golf II: Proceedings of the second world scientic congress of golf (pp. 341 - 347).
London: E & F N Spoon.
USGA & R&A. (2006). Interim Report on the study of Spin Generation.
USGA & R&A. (2007). Second Report on the Study of Spin Generation.
ResearchGate has not been able to resolve any citations for this publication.
Article
A wind tunnel technique has been developed to measure the aerodynamic forces acting on golf balls over a wide range of Reynolds number and spin rate. Balls with round dimples and hexagonal dimples have been investigated. The dimples are found to induce a critical Reynolds number behavior at a lower value of Reynolds number than experienced by a smooth sphere and beyond this point, unlike the behavior of a sand-roughened sphere there is little dependence of the forces on further increases in Reynolds number. A hexagonally-dimpled ball has a higher lift coefficient and a slightly lower drag coefficient than a conventional round-dimpled ball. Trajectories are calculated using the aerodynamic data and the ranges are compared with data obtained from a driving machine on a golf course.
Article
In January 2010, grooves on the heads of golf clubs were mandated to have less volume and rounder edges. The intention of the controversial new grooves design was to make hitting from the rough harder, thereby making driving accuracy more important. We analyze data from 2009 and 2010 to determine the impact of the new rule on golfers on the PGA TOUR. In the 1980's, those golfers who were ranked most accurate in their driving were also ranked highest on the money list. However, this correlation has steadily decreased, to the point where it is now nearly zero. We find that for 2010, the correlation between these two variables is higher, but not statistically significantly so. We then examine whether it was harder in 2010 to hit from the rough, both visually and statistically. Both approaches show that it was no more difficult to hit from the rough in 2010 than in 2009, and perhaps even easier. Lastly, we look into players' strategies to determine whether or not they are playing differently in 2010 to adjust for the new rule. We find no evidence -either visual or statistical -to suggest that players have significantly changed their styles in 2010.
Article
This study examines how PGA Tour golfers' playing strategies offset a ban on technologically superior golf club grooves and how the strategy changes translated into performance changes. The ban, which was implemented at the beginning of the 2010 season, effectively decreased golfers' abilities to spin the golf ball from all on-course environments and offers a unique opportunity to examine offsetting behaviour in the light of a ban on the type of technology. We compare 2009 and 2010 PGA Tour results in a manner consistent with previous studies of offsetting behaviour and golf club groove construction. Our results suggest that offsetting behaviour mitigated the effects of the technological regulations on golf clubs in an economically and statistically significant way, as golfers' performances improved following the technological ban.
Article
Backspin rate and friction coefficients have been studied for a range of commercially available wedges and multi-piece golf balls using a mechanical golfer and a modified pin-on-disc tester. Analysis of shot characteristics for wedges with three different surface roughness values and two golf ball types (two-piece ionomer covered and three-piece polyurethane covered) was carried out using the mechanical golfer, whilst pin-on-disc testing was performed to determine the friction coefficient between the different golf ball covers (with a range of hardness values) and steel discs with a range of surface roughness values seen for different wedges. It was found that the polyurethane covered balls (lower hardness) showed greater backspin than the ionomer covered balls (higher hardness), and showed higher friction values during the pin-ondisc testing. During the mechanical golfer tests, however, it was observed that the ionomer covered balls showed an increase in friction coefficient for increasing surface roughness, although the effect of differences in cover material types was greater than that of surface roughness variation for the same cover material within the range of commercially available wedge face surface roughnesses.
Article
In order to understand the role of surface dimpling on the flow over a golf ball, direct numerical simulations (DNS) are conducted within the framework of an immersed boundary approach for two physical regimes. Computations of the flow over a non-rotating golf ball are reported for a subcritical flow at a Reynolds number of 2.5 × 104 and a supercritical case at a Reynolds number of 1.1 × 105. Grid refinement studies for both Reynolds numbers indicated that characteristics of the subcritical flow could be captured using a mesh of 337 × 106 points, and for the supercritical case using a grid with 1.2 × 109 points. Flow visualizations reveal the differences in separation characteristics between the two Reynolds numbers. Profiles of the mean velocity indicate that the flow detaches completely at approximately 84° in the subcritical case (measured from the stagnation point at the front of the ball), while in the supercritical regime there are alternating regions of reattachment and separation within dimples with complete detachment around 110°. Energy spectra highlight frequencies associated with vortex formation over the dimples prior to complete detachment in the supercritical regime. Reynolds stresses quantify momentum transport in the near-wall region, showing that the axial stress increases around 90° for the subcritical case. In the supercritical regime these stress components alternately increase and decrease, corresponding to local separation and reattachment. Prediction of the drag coefficient for both Reynolds numbers is in reasonable agreement with measurements.
Chapter
Ball launch condition data and clubhead data were measured in order to gain an understanding of the striking characteristics associated with a group of elite golfers using different iron golf clubs. Ten right-handed male golfers were used as subjects (handicap −0.5±1.7). The testing was carried out in a dedicated indoor golf facility. Each golfer hit eight shots with each of four of his own iron clubs (3-iron, 5-iron, 7-iron and pitching wedge). Launch conditions and clubhead data were measured using a stereoscopic high-speed camera system. The mean club head speeds for the group decreased and the mean clubhead angle of attack increased as the club became more lofted. The more lofted clubs produced a higher mean spin rate and higher mean launch angle. Whilst these findings are as expected, the study is novel in providing a scientific database for the competences with irons associated with this elite skill level. It also validates the choice of a single subject that may be used in the future construction of a simulation model designed to investigate iron club striking properties.
Article
At the beginning of the twenty-first century, there are 30,000 golf courses and 55 million people who play golf worldwide. In the USA alone, the value of golf club memberships sold in the 1990s was US dollar 3.2 billion. Underpinning this significant human activity is a wide variety of people researching and applying science to sustain and develop the game. The 11 golf science disciplines recognized by the World Scientific Congress of Golf have reported 311 papers at four world congresses since 1990. Additionally, scientific papers have been published in discipline-specific peer-reviewed journals, research has been sponsored by the two governing bodies of golf, the Royal and Ancient Golf Club of St. Andrews and the United States Golf Association, and confidential research is undertaken by commercial companies, especially equipment manufacturers. This paper reviews much of this human endeavour and points the way forward for future research into golf.
The effect of impact conditions on golf ball spin rate
  • B B Lieberman
Lieberman, B.B. (1990). The effect of impact conditions on golf ball spin rate. In A.J. Cochran (Ed.), Science and Golf (pp. 225-230). London: E & F N Spoon.