HOLLOW GOLF CLUB HEAD MODAL CHARACTERISTICS - DETERMINATION AND IMPACT APPLICATIONS

The design of modern hollow golf club heads is a labor-intensive proce ss involving extensive performance testing both by robotic and real go lfers. This paper describes how, by correlating club head mechanical b ehavior with functional performance, it will become possible to use va lidated computational models to predict this performance as well as re lated contributions to the ill-defined concept of ''feel.'' Successful use of experimental modal analysis to validate a hollow golf club hea d finite element model is reported. Modal tests employing noncontactin g, laser-based transducers facilitated identification of the natural f requencies and corresponding modeshapes for the three main surfaces of the club head. The experimental data suggest predominantly different modal characteristics for each surface, and this compares favorably wi th equivalent data obtained from the finite element model. The modal d ata are also used to identify surfaces responsible for particular freq uency components present in the club head impact sound spectrum. The p otential for detailed impact performance prediction using the finite e lement model is further demonstrated by comparison of computed and exp erimental club head acceleration measurements recorded during simulate d and actual club-ball impacts.