2007 Volume 48 Issue 6 Pages 1249-1253
A new method to more accurately estimate the impact mass when an elastic ball is impacting on a surface of an elastic plate is suggested. Conventionally, frequency ratio (FR) and center frequency techniques have been widely used for a mass estimation. However, these methods do not work when the mounting effect of a sensor is dominant and/or the operating background noise becomes high. Thus a new technique to eliminate these effects by using a time-frequency analysis is attempted and verified through an experiment. It is revealed that the proposed method is valid for estimating the center frequency of an impact response signal easily even in a noisy environment, thus making a mass estimation of an impact source on a plate type structure more successful than the conventional techniques.
