Estimation of Club Head Posture during Golf Swing using three-dimensional FEM model

Abstract

Golfers expect to hit a golf ball with enough distance for golf clubs, especially in the case of driver. Therefore, golf clubs are designed to satisfy golfers' demands. However, not only volume of head of a golf club but also coefficient of a golf club was restricted. Therefore, golf club developers use a variety of methods to customize clubs to individual golfer. One such technique is “database fitting,” established by Sumitomo Rubber Industries, Ltd. (SRI). In the future, golf club developers would like to provide shafts customized to fit each individual golfer. In order to do so, it is necessary to predict shaft movement during a golf swing via simulation. Previous studies simulating shaft movement during a golf swing demonstrate shaft movement using a finite element method (FEM) model with shaft flexibility and the golfer's grip. As a result, there was a difference of deflection value at impact timing. In order to solve this problem, we considered that the deflection torque generated by the cross product of the shaft deflection. Therefore, we made a simulation model in consideration of the deflection torque. To verify the effectiveness of this model, the shaft movement was measured with a 3D motion capture system (VICON). The sampling frequency was 500 Hz and markers were attached to the shaft. Examinees were one average golfer. We compared simulation and experiment. As a result, we reached conclusion that the model in consideration of the deflection torque can reproduce real golf swing.