102 The measuring method for analyzing the topspin technique in tennis

Abstract

As hitting topspin ball has been becoming popular, precise researches of friction between the string-bed and ball were carried out. But there were not much researches of human body or technique. The aim of this study is to make the measurement system to clarify the technique of swinging a racket. That swing path must be different by the grip angle. If the correct grip angle becomes clear, players will be able to acquire the swing technique quickly without the injury of wrist. First, it is necessary to know overall movement of hand, forearm and racket. By using strain gauges, we measured the force that occurs on the string-bed, and the strain that appeared on the racket throat. From inertial sensor attached on hand and forearm, we measured the acceleration and angular velocity of them. From this experiment, we found these data are useful for analyzing the swinging technique.