Item: Modal analysis: a dynamic ski test
Title: Modal analysis: a dynamic ski test
Proceedings: Proceedings of the 1994 International Snow Science Workshop, Snowbird, Utah, USA
Authors: Mr. Bob Rice, Dr. Rand Decker, Dr. Richard W. Shorthill
Abstract: The dynamic behavior of skis is investigated using a digital spectrum analyzer and measuring both the input force and the response motion. The natural frequencies, damping and mode shapes· are measured. Currently, ski tests are limited to static measurements such as, the bending or twisting of the ski in transverse directions with various fixed weights and measurements of moment of inertia. However, matching skis by their frequency response and damping values will provide a more accurately matched pair when combined with static measurements. In addition, our skis are tested dynamically after every ten days of use. By this method, the change in the dynamic response of the ski is tracked. This data provides information on the life of skis Le., maximum performance and when it is time for a new pair. Skiers can establish an optimal profile for the kind of ski they like, to find that "perfect pair of skis". Modal analysis may provide a good test to establish whether a ski has been internally damaged, or as the ski manufacturers term "has gone flat". The dynamics of a damaged ski are' significantly different from that of the undamaged one.
Keywords: skis, ski damages
Digital Abstract Not Available