Effect of Inertia for Shaft Movement generated by a Golf Swing

抄録

In aprvious study on representing shaft movement during a golf swing, we made a simulation model expressing golf club movement during a golf swing and demonstrated 3D club movement via an FEM model with shaft flexibility and the golfer's grip. We then computed the inertia force as input data. As a result, we concluded that this simulation model is able to represent behavior during the golf swing. However, there was a difference of deflection value near impact timing. Therefore, we are concerned that there is another cause for the shaft's deflection. Thus, we represented the deflection torque generated by the cross product of the shaft deflection and the inertia force. As for computing these input data, the shaft movement during the swing was measured with a 3D motion capture system (VICON Blade). The sampling frequency was 500 Hz and markers were attached to the shaft. Examinees were two average golfer's. Using these measured data, we simulated the shaft movement under four grip conditions with different grip stiffnesses. For the results of this simulation, the simulated deflection behavior was close to the measured deflection behavior with the deflection torque. Moreover, considering the fit grip condition, the deflection behaviors were improved. As a result of this research, we reached the following conclusion that the shaft movement is generated by a combination of the grip condition, vibration component of inertia force and the torque generated by the cross product.