The performances of a table tennis racket can be qualified with several adjectives like: fast, slow, stiff, adhesive, controllable, etc. These qualifications are subjective since they are relative to the sensory analysis made by each player. It appears that the noise produced at the ball impact on a racket has a great influence on the opinion that a player can give about a racket. Moreover, the sound emitted at the stroke can be appreciated differently among several players. Hence a good sound may give a positive a priori to the player about the racket appreciation. The work presented first demonstrates the correlation between the acoustic frequency spectrum and the vibration frequency spectrum of a racket following the ball impact. The analysis is first performed on the racket blades without rubbers glued on. The vibration modes that produce the sound at the ball impact were identified experimentally and correlated with some numerical predictions. It is shown that two main vibration modes are responsible of the sound emitted. In second, the influence of the blade plywood composition is studied. Several prototype racket blades have been designed with some differences between them on: the thickness of the plies, the wooden essences, the wood fiber orientation. The experimental results obtained permit to clearly state about the effectiveness of these design parameters on the impact sound. Then the influence of the rubbers (coverings) glued on both blade sides is studied. The vibration modes are the same but the frequencies are lower. The sound can be qualified as sharp, long, clear, deep, hollow or plain. In the last part of this study, the experimental observations obtained at the laboratory are compared with the results of a sensory analysis performed with the same prototype rackets by a panel of high level players. It is shown that the classification made by the players is consistent with the experimental observations.
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