Measuring Canopy Anomaly Influence on Golf Putt Kinematics: Errors Associated with Simulated Putt Devices

Abstract

Simulated putt devices (SPDs) are marketed to golf course superintendents to steer agronomic inputs intended to improve consistency of ball roll distance and direction on green canopies. Although research has demonstrated the use of SPDs to contrive green management practices that improve ball roll distance, no peer‐reviewed research has evaluated their ability to measure golf ball directional behavior, despite the existence of products marketed for that purpose. Laboratory and field research was conducted in Blacksburg, VA, to evaluate sources of error that may influence inferences made using SPDs on golf greens. The data suggest that commercially available SPDs impart directional imprecision that is orders of magnitude greater than custom‐built flexible ramp and mechanical putter devices. A significant source of this directional imprecision between SPDs is associated with wobble, assessed by high‐speed videography, while balls were rolling down the Greenstester, PELZmeter, and US Golf Association Stimpmeter. The influence of 13 golf ball brands was secondary to that of SPDs on ball roll directional and distal imprecision. A novel method of scoring the balls’ direction was employed in the field by allowing balls to strike pressure‐sensitive paper 0.3 m before terminal motion. Repeatedly rolling balls in the same track increased ball roll distance and decreased ball directional imprecision. Brushing the creeping bentgrass (Agrostis stolonifera L.) canopy between ball rolls eliminated these effects. These results bring into question the utility of commercially available SPDs to steer agronomic decisions on greens, especially for the purpose of improving ball roll directional precision, but prove that subtle distinctions in canopy trueness can be measured using appropriate methods.

Measuring Canopy Anomaly Influence on Golf Putt Kinematics: Does Annual Bluegrass Influence Ball Roll Behavior?

“…Our data suggest that the Greenstester is not able to parse the impact of annual bluegrass on ball directional behavior (Fig. 2), and previous work suggests that on‐device wobble and legacy effects of repeated ball rolls in the same track could significantly affect data obtained using the Greenstester and Holing Out Protocol (Rana and Askew, 2017).…”

“…Because of popularity among both researchers and golfers and performance in previous laboratory research compared with 12 other ball brands (Rana and Askew, 2017), the Titleist Pro V1 golf ball with a true center of gravity was used for this study. The Greenstester and a custom-built mechanical putter were used to propel the golf ball across areas of visibly pure creeping bentgrass or transects that contained a patch of annual bluegrass and were calibrated as described in previous studies (Rana and Askew, 2017). The simulated putt devices (SPDs) were arranged to roll the ball 150 cm, but the ball was arrested 30 cm short of this distance by a metal plate with an affixed pressure-sensitive paper, as described in previous studies (Fig.…”

“…Transects were selected on both level and sloped areas of the greens. A golf ball with a true center of gravity was rolled repeatedly from the same location within a given SPD main plot and turfgrass canopy subplot such that greens canopy was brushed between each consecutive ball roll using techniques described in previous studies (Rana and Askew, 2017).…”

“…The simulated putt devices (SPDs) were arranged to roll the ball 150 cm, but the ball was arrested 30 cm short of this distance by a metal plate with an affixed pressure-sensitive paper, as described in previous studies (Fig. 1; Rana and Askew, 2017). Strike marks on the pressure-sensitive paper were scored from 10 ball roll subsamples for a given experimental unit.…”

“…We hypothesized that a putting green surface imperfection, such as an infestation of annual bluegrass, will increase directional imprecision and bounce and decrease acceleration of balls rolled over it. By employing several methods and techniques derived from previous laboratory and field research (Rana and Askew, 2017), field trials were conducted on in‐play golf greens with the objective to assess the influence of a small patch of annual bluegrass on ball roll directional imprecision, ball bounce, and ball acceleration while rolling across an otherwise visibly pure and uniform creeping bentgrass ( Agrostis stolonifera L.) green canopy.…”