Patrick Drane

The Effect of Baseball Construction on the Game of Baseball (P275)

Many leagues have introduced or tightened performance regulations of baseball bats over the past decade as the technology to quantify their performance has improved. However, little to no emphasis has been spent on understanding the range of baseballs that are used across the different levels of play, and as a result, baseball regulations are typically limited to size, weight and coefficient of restitution at 26.8 m/s (60 mph). This paper will explore many of the different baseballs that are used and highlight the similarities and the differences with respect to the construction, overall size and weight, and performance among these baseballs. Coefficient of restitution, both the standard using a flat wood block and cylindrical using a solid-steel half cylinder, and compression tests are used to evaluate the performance in a controlled lab environment..

Special section on “Technology in Sports Training”

The use of technology is playing an ever increasing role in sports. Engineers and scientists are taking advantage of advances in modeling and materials in the design of boat hulls, oars, swimsuits, running shoes, clothing, golf clubs, skis, snowboards, bikes, pole vaults and so on to allow the athlete to increase performance over time. Technology has the potential to play a significant role not just in the equipment but also in the training of the athlete. Access to such technology can be the difference between whether an athlete is a contender for gold or just another participant in the sporting event. There are numerous examples of close finishes where the difference between gold and silver was decided by a fraction of a second. At the 2012 London Summer Olympics, Nathan Adrian (USA) swam his way to victory in the 100-m Freestyle by only 0.01 s. Stretching ahead with his fingertip, Michael Phelps seized the 100m Butterfly in the same split second just 4 years prior at the Beijing Summer Olympics. Although Nicola Spiriting (SUI) and Lisa Norden (SWE) were clocked at exactly the same time (1:59:48) in the 2012 Women’s Triathlon, Spiriting took the gold after it was determined that her torso leaned a mere 6 in ahead of Norden, making it the closest finish in Olympic Triathlon history. Ekaterina Karsten (BLR) crossed the finish line at 7:28:14 at the 2000 Olympic Games in Sydney, while her Bulgarian competitor clocked in just behind her at 7:28:15 in the Women’s Single Sculls event. In the Barcelona 1992 Games, Yolanda Gail Devers won the Women’s 100-m track event in a blanket finish by only 0.06 s; the fifth place finalist was less than one-tenth of a second behind her. As a result of such close outcomes, coaches, trainers and athletes are always searching to find ways to shave that fraction of a second off of their time. In this collection of articles, the authors share how technology in sport can be used to gain insight into what separates a good athletic performance from a great athletic performance. Each of the articles presents one or more instrumentation techniques to track parameters such as absolute position and orientation, motion tracking, biomechanical feedback, the complementary use of video and data analysis to guide in the training process. Perrat et al. explored the ability of using an UltraWide Band (UWB) for tracking the positions of athletes during indoor wheelchair court sports. Because the sporting event is indoors, global positioning system (GPS) is not an option. The value of the system was its ability to capture the absolute distance traveled by each participant and their relative positions during play. Ruffaldi, Peppoloi and Filippeschi present a sensor fusion model for integrating wearable inertial measures with sensors for rowing in indoor and outdoor environments. Of specific interest in this article is the ability to track isolated limb motion. The wearable device has the advantage over optical systems that may suffer from occasional blind spots. The device tracked the motion of each limb during rowing, and the associated outcome was documented. These pieces of information gave insight to the coaches and athlete into what changes in motion need to be addressed in training to increase performance. The collection ends with an overview of the use of technology and experimental based engineering tools to facilitate sport-specific skill acquisition and improvements in performance. In this article, McNitt-Gray et al. share how an understanding of multiple factors which influence performance can often be advanced by using readily available, low-cost technologies. Such technologies are often a combination of video for motion analyses and complimentary data capture, for example, a force plate during a gymnast landing. Through this understanding, the coach and athlete can design a training program that will lead to improved performance. We hope that you enjoy this collection of articles, and we invite you to contribute articles to this journal describing your research on the use of technology in sports training.

An Experimental Investigation of the Effect of Use on the Performance of Composite Baseball Bats (P274)

The choice of materials used to make baseball bats has evolved over the years from traditional solid wood to aluminium and now to composites. To determine whether or not a bat’s design is in compliance with the batted-ball performance standard for a given league, a new bat is tested in a hitting machine where the bat is subjected to a limited number of hits. Considering the material behaviour that occurs within a composite material subjected to numerous impacts, the batted-ball performance of composite bats can theoretically improve with use as the polymer-matrix develops microcracks. These microcracks can soften the barrel of the bat which may allow the trampoline effect to increase. As the trampoline effect increases, there is potential for the batted-ball speed to increase. This paper will discuss the observed evolution of the performance for six currently popular composite baseball bats that were subjected to cycles of performance testing followed by repeated use in a controlled laboratory setting. None of the six composite baseball bats exhibited a significant change in performance. Some of the composite bats did exhibit poor durability.

Experimental Investigation of Youth Baseball Bat Performance (P273)

The batted-ball performances of youth wood and nonwood bats are examined through experimental methods. The goals of the study are to build a database of performance data on youth bats using a hitting machine in a controlled laboratory environment and to examine how the lab data compare using three performance metrics including the current BPF certification metric. The performance metric that best correlates the lab data with field performance is found to be the BBS metric.

An Experimental Investigation of Baseball Bat Durability

The service life of a baseball bat is a function of its durability. All wood bats crack, and ash bats exhibit flaking of the barrel due to repeated impacts. In aluminum and composite bats, repeated impacts can cause a change in the material properties, which in turn can lead to dents and microcracks that ultimately coalesce to form macrocracks. A test machine for simulating essentially any field condition for bat/ball impacts has been developed to study bat durability. The system uses an air cannon capable of firing a baseball at speeds up to 180 mph at a stationary bat which is supported in a grip that replicates a player’s hands. This paper will describe the system, present some supporting analysis of the gripping method, and present results of tests from wood and aluminum bats.