四ローラ式ピッチングマシンの研究

抄録

There are many players for ball game sports such as a baseball, tennis and table tennis etc. The ball pitching machine (shooting machine) is used for practice of the ball sports, and it is widely familiar. However, there are few pitching machines that can throw a ball with a gyro spin, such as a football or rifle bullet, in which the axis of the ball spins in the same direction as the ball travels. In this study, we have developed a new baseball pitching machine with a launch mechanism that uses four rollers (two launch and two gyro rollers). From the results of the throwing tests, the pitching machine can throw the balls with a wide range of speeds from 22.2 m/s (80 km/h) up to 44.4 m/s (160 km/h) and all pitch types (no-spin, fastball, curveball, slider and gyroball) at any directions. In addition, the baseball machine was capable of throwing a ball with higher control accuracy (less than 116 mm) compared to current pitching machines.