A Study of Softball Pitching Machine by Windmill Throwing

Abstract

Softball is a very popular sport among people irrespective of age or gender in Japan. In the present work, by adding a holding device to the arm-type pitching machine for throwing softball, we develop a prototype machine to realize a real pitcher's windmill throwing (i.e. the one arm revolution is performed as well as windmill rotation). We carry out pitching experiments to verify the pitching performance of the developed machine, and investigate the shape influence of the curve hand that can throw curveballs with small eccentricity of the spin axis and large change of arrival position by pitching simulation using finite element analysis. In special, we design the optimal shape of the curve hand according to the finite element simulation and evaluate the pitching performance by pitching experiment at last. As a result, we confirm that the machine can pitch softball as a real pitcher's windmill throwing that can be utilized in batting practice.