A method of evaluating the vibration characteristics of a golf club comprises identifying the natural frequencies of vibration of the golf club through a pseudorandom vibrational excitation of the club. The club is then excited at least at some of the identified natural frequencies and the club head is observed under a strobe light to identify and locate on the face of the club head the node lines corresponding to the vibrational mode shape for these natural frequencies. The intersection pattern of the node lines as observed and mapped on the club face and the offset of this pattern from the presumed sweet spot provides important information as to the likely feel this particular golf club will have. In addition, a method of impacting a golf club at the sweet spot with a predetermined force is disclosed to simulate the impact of the club with a golf ball. The frequency response curve represented by the vibration levels as a function of frequency is a useful indicator of the gross or absolute levels of vibration of the club. Various golf clubs can be compared against one another by comparing the areas underneath the frequency response curves for the various clubs.
ISURF Reference Number
Iowa State University Research Foundation, Inc.,
McConnell, Kenneth G. and Houser, Guy M., "Method of evaluating the vibration characteristics of a sporting implement such as a golf club" (1997). Iowa State University Patents. 184.