卓球用ラバーにおける粒構造の三次元定量化にもとづく性能評価指標の提案に関する研究

抄録

The objective of this study was to develop an evaluation index for the performance of a table tennis rubber with pimples structure and to investigate the effectiveness of the index by grasping effects of the index on the ball rebound behavior using finite (FE) element analyses. A porosity, which was defined as the ratio of the volume of pimples that depended on the pimple height and diameter and the distance between pimples, was proposed as the index for evaluating the rubber in view of the 3D shape of pimples structure. The FE model of the sandwich rubber which was composed of a rubber and foam layers was constructed with non-linearity, strain rate dependency, and energy absorption. The high accuracy of their material models has been confirmed by comparing with experimental results. Impact analyses were conducted using the developed models of ball and rubber with different porosity. The tendency of simulation results of the ball rebound behavior tended to change with a certain value of porosity. It is considered that the trend is due to the fact that the effect on the rebound behavior tends to be different between the case which the porosity changes in the range smaller or larger than the value. The porosity, which can express changes in the rebound behavior of the ball, has the potential of evaluating the rubber with pimples structure.