The estimation of modal parameters due to the change of the sweet spot by the structural modification of a tennis racket.

In this paper, we report that the change in the vibration characteristics of a tennis racket due to structural modifications were identified. The modifications consisted of a change in the material of the frame and the attachment of a damping material to the grip. Due to these structural modifications the sweet spot was changed. The most effective modal parameter for the extension of the sweet spot was stiffness as determined by sensitivity analysis. Hence, the change of the sweet spot was predicted by changes in stiffness. There was good agreement between the predicted and measured values of the sweet spot.