A-9 Effect of Impact Velocity on Bat-Ball Coefficient of Restitution of Metal Baseball Bat

Abstract

Wood, metal, and various composite materials are used in manufacturing baseball bats. Metal bats are advantageous over traditional wooden bats in terms of improved strength, lower cost, durability, etc. Knowing the restitution performance of a metal bat according to the ball's wide range of impact velocity is important. In this study, a numerical analysis model of the metal bats was designed, and the effect of impact velocity of the ball on bat-ball coefficient of restitution (BBCOR) was examined from both sides of the experiment and numerical analysis. Impact velocity of the ball was changed from 33 to 67 m/s, and the rebounding velocity of the ball was measured during the experiment and numerical analysis. Furthermore, it was determined whether BBCOR depends on either the restitution performance of the ball or the bat. Subsequently, BBCOR was shown to decrease with increasing impact velocity, and the numerical analysis result showed that the restitution performance of the ball greatly influenced BBCOR.