Figure 3 - uploaded by Paul Glazier
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![(a) The swingweight of a golf club is commonly defined as the first moment of mass about a fulcrum 14 inches from the butt end of the grip and is measured using a 'lorythmic' swingweight scale (analogue version shown for illustrative purposes). When mounted on the scale, a moment is generated about the fulcrum by the weight, mg, of the club. the sliding mass, m, is then positioned to balance the club moment. Swingweight is calculated by multiplying, m, by its distance, d, from the fulcrum and the resulting number being divided by two (i.e., two inch-ounces represent one swingweight). Alpha-numeric values ranging from A0 to G9 (i.e., A0-A9, B0-B9, . . . , G0-G9) are used to designate swingweights with each swingweight point being progressively heavier than the preceding swingweight point; (b) the moment of inertia or second moment of mass of a golf club is defined as the resistance to rotational acceleration about an axis at the butt end of the grip that is approximately normal to the swing plane at impact and is commonly measured using a compound cantilevered device. Once clamped to the cantilever, the club is retracted and released, allowing it to oscillate back and forth. the cycle period, t, is measured and, with the known elastic constant, k, of the previously calibrated internal spring, the moment of inertia, I, of the club is calculated (I=k[t/2π] 2 ) and displayed on the digital readout.](profile/Paul-Glazier/publication/359942885/figure/fig3/AS:1152833890070529@1651868426573/a-The-swingweight-of-a-golf-club-is-commonly-defined-as-the-first-moment-of-mass-about.png)
(a) The swingweight of a golf club is commonly defined as the first moment of mass about a fulcrum 14 inches from the butt end of the grip and is measured using a 'lorythmic' swingweight scale (analogue version shown for illustrative purposes). When mounted on the scale, a moment is generated about the fulcrum by the weight, mg, of the club. the sliding mass, m, is then positioned to balance the club moment. Swingweight is calculated by multiplying, m, by its distance, d, from the fulcrum and the resulting number being divided by two (i.e., two inch-ounces represent one swingweight). Alpha-numeric values ranging from A0 to G9 (i.e., A0-A9, B0-B9, . . . , G0-G9) are used to designate swingweights with each swingweight point being progressively heavier than the preceding swingweight point; (b) the moment of inertia or second moment of mass of a golf club is defined as the resistance to rotational acceleration about an axis at the butt end of the grip that is approximately normal to the swing plane at impact and is commonly measured using a compound cantilevered device. Once clamped to the cantilever, the club is retracted and released, allowing it to oscillate back and forth. the cycle period, t, is measured and, with the known elastic constant, k, of the previously calibrated internal spring, the moment of inertia, I, of the club is calculated (I=k[t/2π] 2 ) and displayed on the digital readout.
Source publication
It has previously been argued that science has only made a limited contribution to the sport of golf, particularly the human element. This lack of impact could, in part, be attributed to the absence of an appropriate theoretical framework in most empirical investigations of the golf swing. This position paper outlines an ecological-dynamical approa...
Contexts in source publication
Context 1
... of the few exceptions in the literature, however, was the study of Harper et al. (2005), which examined the effect of swingweight on the perception and performance of drivers. Swingweight provides a measure of weight distribution and is considered to be the industry standard for 'matching' golf clubs across a set (see Figure 3a for a schematic detailing how swingweight is measured). Based on data obtained from 30 skilled golfers using four drivers of different swingweights (C7, D0, D5, E0), Harper et al. (2005) concluded that the golfers, on average, were unable to perceive small changes in swingweight (±3 points) and that these changes had little impact on player performance in terms of clubhead speed and impact location. ...
Context 2
... alternative to swingweight matching, which has only been used sparingly in the custom fitting of golf clubs and has seldom featured in the scientific literature, is moment of inertia matching. The moment of inertia of a golf club can be defined as the resistance to rotational acceleration about an axis at the butt end of the grip that is approximately normal to the swing plane at impact (see Figure 3b for a schematic detailing how moment of inertia is measured). Both mechanical engineers (e.g., Budney & Bellow, 1982) and club fitters (e.g., Wishon, 2011) have suggested that moment of inertia is the only method of truly matching golf clubs and ensuring they have identical swing feel. ...
