IDENTIFICATION OF THE IMPACT LOCATION ON A PLATE USING WAVELETS

This paper presents an experimental method that has been developed for detecting flexural waves in plates by the use of piezoelectric films. The recorded signals are analysed by a 'wavelet transform' to determi ne arrival times of waves at different frequencies. These arrival time s are used in conjunction with an optimisation method to identify the location of the impact (i.e. the x- and y-coordinate of the source loc ation). Also, the time lag between the instant of the impact and the r ecording of the signals together with the group velocity of the disper sive waves are specified. Close agreement is observed between the expe rimentally determined results and the exact solutions. This technique is a valuable method for identification of source locations that may b e applied to problems related to in-service impact loading of structur es, seismic data from earthquakes, and to acoustic emission signals fr om propagating cracks. (C) 1998 Academic Press.