改良型アーム式ピッチングマシンの研究

抄録

Baseball pitching machine is divided into the "arm", "air" and "rotor (roller)" types in general. The arm type machine similar to throwing operation of a real pitcher's arm has the advantage which is easily to take the timing in the ball hitting. From the result of the throwing experiment using the arm type pitching machine, the spin rate of the pitched ball was faster approximately twice than a real pitcher. In this study, it was made experimentally the improved arm type pitching machine. The new hand device for throwing ball was changed the length, and was attached a thumb which can be grip and open. It is able to change the ball spin rate by the hand with the release control at the throwing time. The throwing experiments and simulations were performed using the improved machine. The improved arm type pitching machine was had low ball spin rate (less than 2500 rpm) and high throwing accuracy (approximately 180 mm) than the conventional one.