Ten-pin Bowling Technologyby Michael Russell For the machine which sets bowling pins, see pinsetter. The behavior of a rolling ball on a surface is controlled by several factors, the most obvious being the bowler's delivery. In the delivery, the bowler can advantageously use or fight (intentionally or unintentionally) the force of gravity. After the ball is on the surface of the lane, a complex interaction of friction, gyroscopic inertia and gravity becomes a factor that can range from subtle to perhaps amazing. These environmental influences can be segregated as either lane conditions or ball characteristics. Both are regulated by the USBC, as are the pin characteristics. Technological changes, throughout the history of the sport, often required new regulations, and this continues today, often with great debate. The controversies usually involve scoreability. While low scoring can be a problem, it is the increasing frequency and degree of higher scoring that irks the purists, who say that it is spoiling the integrity of the sport. Among advanced players, there is little argument about whether technological changes have enabled higher scoring - it has. Yet there are those who have seen their scores decline, often due to not changing their technique or balls appropriately. Some argue that such high technology unfairly effects competition, making high scores effectively a product of how much money one spends on equipment. Historically, up until the late 1960s, the USBC honor awards (for 300 games, 800 series, etc.) were rarely won genuine treasures. As things started to change, an organization named "The Foundation" comprised of experienced lane maintenance experts and many distinguished bowlers, including members of the Professional Bowlers Association (PBA) and the United States Bowling Congress (USBC) Halls of Fame, was founded in 1966 with the goal of addressing these serious issues. The Foundation members at that time made the statement that under the current environment in bowling they "could no longer guarantee a lane condition that would be accepted by the contestants, coaches and observers as fair and equitable." In 1989, Bob Strickland wrote that bowlers know it is possible to bowl bad but score good, or worse, to bowl good but score bad. It can be confusing to players as they learn the game. For more experienced players, notably older ones who have locked themselves into some technique that no longer works as well, it can become quite frustrating. In the early 1970s the first plastic balls became widely available, just a few years after the first urethane coatings were applied to the old wood lanes. Those and subsequent changes have been altering the physical scoring factors. These and the ever present opportunity to use lane oiling patterns to make targeting easier, is a cause for concern. Honor scores have increased by several thousand percent on a per capita basis in the 25 year time period from 1980 - 2005. The USBC, for various reasons, has not been able to regulate these changes well enough to protect the integrity of their honor score award program. So they have cheapened their intrinsic value and created other workarounds. In response to the view that higher scoring lane conditions are spoiling the integrity of the sport, the USBC introduced in 2000 the Sport Bowling Program which offers a different optional league certification. It understandably requires higher bowler fees, and the USBC provides a separate set of honor awards. In "Sport Bowling," lane conditions are more highly regulated and controlled than in traditional leagues and the oiling patterns used are generally more even with regards to volume and ratios of oil across the surface of the lane. "Sport Bowling" conditions are also used at the major championships of professional bowling (the U.S. Open, the USBC Masters, the PBA World Championship, and the PBA Tournament of Champions). One of the most contentious issues that has arisen is whether there should be a Standard Ball for the sport of bowling, or at least whether significant restrictions should be imposed on bowling ball technology. Other considerations have been noted with regards to the weight of the bowling pins, lane oiling techniques, and with the construction materials and techniques used to build bowling lanes. A bowling ball is not an absolutely uniform sphere - the gripping holes (and sometimes a balance hole) alone make that impossible. Bowling ball materials, during the history of the USBC, have evolved from wood, to rubber, to plastic, to urethane, to reactive urethane, to particle, and to epoxy. Wood balls are now just museum pieces. Rubber balls are almost as hard to find - you may still see them offered to casual bowlers at bowling centers, from their racks for those who don't own their own ball. Bowling balls have been constructed with a core made of one material, a spherical coverstock ("cover" or "shell") and a "pancake" weight block of denser material intended to compensate for the gripping holes. In the early 1970s, people began experimenting with the hardness of the plastic balls, notably PBA member Don McCune, who invented the "soaker" - a plastic ball he softened "in the garage" with chemicals. These and balls subsequently manufactured with the resulting softer cover came under USBC scrutiny because of the increased scoring. A ball hardness rule was established, which barred some of the softer balls. At some point in ball making and drilling the USBC introduced ball balance regulations to prevent people from taking advantage. It was possible to drill the grip at a location relative to the weight block so that it would achieve some effect, such as to help the bowler make it roll earlier or hook more. Prior to about 1990, the USBC "static" ball balance regulations were adequate. The core was usually a uniform sphere centered inside the ball. Then competition among ball manufacturers motivated the production of balls designed to offer more than the "static balance" tricks. Materials and fabrication changes have since allowed the assembly of balls whose interior components have a much greater range of density, thereby offering a new ball choice that, in physics terms, involves the moment of inertia of a solid sphere. Eventually, "dynamic balance" regulations had to be adopted. In order to continue this discussion, a systematic description of ball rotation must be introduced. For various formulaic purposes, physicists divide rotation into three components, assigning portions to x, y and z axes that are mutually perpendicular. For bowling, the x-axis can be assigned to a line that is parallel to the foul line, the y-axis to the line parallel to the boards, and the z-axis to the vertical. Forward-roll is rotation about the x-axis, side-roll is rotation about the y-axis and mid-roll (or spin) is rotation about the z-axis. The pure full-roller delivery is a combination of forward- and side-roll only. Semi-rollers include spin. Spinners may have very little side roll. In a very strict physics sense, a ball may be delivered with rotation, but usually not in a roll, because that would imply complete traction. The technique of the great majority of bowlers involves a delivery that starts the ball in a skid that evolves into a roll that hooks into the pins. It has been known since before the 1960s that a "full-roller" type of delivery does not hook as well as "3/4 rollers" on oily lanes. On successive rotations, the "full roller" repeatedly contacts the lane on the same full circumferential circle, on which the oil accumulates, making it harder for the side-roll to find traction and create hooking action. The "full-roller" had been the dominant choice before the changes in lane coatings and oil. The "semi-roller" is now preferred (it may also be called "3/4 roller" or by other slang terms). With a 3/4-roller a bowler puts the ball into a rotation whose contact ring is smaller, and on successive rotations enlarges (subsequent examination of the ball often shows a flaring of the circles of oil). This is because at every spot along the circle friction reduces the rotation, and that includes the spin component, causing rotation on a continually larger circle. This has the effect of bringing relatively dry ball surface in contact with the lane, increasing traction for both forward-roll and side-roll. It probably goes without saying why bowlers often wipe oil off the ball. Another effect of ball imbalance (either static or dynamic) is the ability to introduce gyroscopic effects on the rotation. The component of imbalance along the rotation axis provides a leverage that can change the orientation of the axis on its horizontal plane, an action physicists call precession. It is basically the same thing as a spinning toy top "going around in a circle." In the case of a rotating bowling ball, as it moves along the lane, there is only time for its total rotation axis to move along a short arc, but this is enough to reorient the total rotation so that some of the forward-roll becomes side-roll, increasing the side-roll provided in the bowler's delivery, thereby achieving more hook. It is possible to use dynamic ball balancing to achieve a stronger gyroscopic effect than static balancing alone. The advent of dynamic ball balancing meant that bowlers could achieve "ball flare" without the need for a 3/4 roller delivery, and more hook. Additionally, balls with covers that create higher friction, such as "particle" balls, provide for more traction and hook. Bowlers are embracing these choices, buying balls whose characteristics complement or enhance their deliveries. It is the opinion of many people in the bowling community that these advances in bowling ball technology have actually undermined bowling skill and have made it more difficult for lane maintenance personnel to lay out fair and credible conditions for participants. This is because advanced players using hi-tech balls "need" more oil to score high and might complain about the radical behavior of their balls on "dry" lanes. At the same time, less aggressive players might complain when they can't get their balls to hook. These complaints have actually been part of the game throughout USBC history. It's just been a matter of which group prevails within the USBC - or what new technology comes along next.
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