野球用金属バットの振動と打撃性能に関する研究

抄録

Recently, a variety of baseball bats are sold. The materials used in baseball bat are made from the wood, the aluminum or the FRP. The percussion performance is one of the keys to its selling well. The character called sweet spot is used to evaluate the percussion performance. But the relations between the sweet spot position and mechanical characteristics are unclear. First, sweet spot position is theoretically pinpointed by the modal analysis and the energy theory. The closer collision is to the node of mode, the more rebound. And the closer collision is to the center of gravity, the more rebound. Next, the theory is tested by experiments. The first node and second node are pinpointed by the experimental modal analysis. The most reflective position is pinpointed by the collision experiment. In conclusion, the first node should be used for the sweet spot position. The center of purcussion is poor markers of the sweet spot.