抄録
Regarding softball bats made by fiber reinforced plastics (FRP), various products such as single-layer or multiple-layer structures have been developed. In this study, to elucidate the restitution characteristic of the FRP softball bat, the basic characteristics of five types of FRP bats and a metal bat were measured and softball impact tests of each bat were conducted. We investigated the relationship between the bat-ball coefficient of restitution (BBCOR) and the deflection or deformation of the bat and found that the BBCOR of the multiple-layer bat was greater than that of the single-layer bat, and the BBCOR of each bat was influenced by the deformation of bat at the ball impact point.
