Measuring Coherency of Human-Induced Rhythmic Loads Using Force Plates

Abstract

This paper presents the results of an experimental study on measuring and quantifying the coherency of crowd-rhythmic movements. Two instrumented force plates were used to independently measure the load-time histories of sets of two volunteer subjects performing rhythmic movements. Subjects were asked to synchronize their motion to audible signals played at various frequencies. We observed that the coherency of motion varies as a function of the frequency of motion. In addition to auditory effect, the coherency is controlled by a visual effect (i.e, subjects synchronize their motion with respect to the musical beat and movements of one another). Statistics of the coherency of motion are presented for subjects standing in two different orientations, and a suitable type of probability-distribution function is suggested.