An Analysis of the Dynamic Characteristics of a Force Plate

Abstract

Experiments have been performed in which the ground reaction force during walking has been measured simultaneously by two different means; a shoe having a spring-loaded heel and fitted with a transducer was worn by subjects walking over a force plate. Discrepancies in the two sets of results led to an analysis of the dynamic characteristics of the force plate which was facilitated by comparing the results of the two measuring systems. The increase in the total mass of the system as the body lands on the plate reduces both the damping ratio and the natural frequency of the force plate system, causing an increase in the dynamic magnification. These effects are analysed quantitatively and recommendations are made for the future design of force plate systems.

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