Damage detection with concentrated configurations of piezoelectric transducers

Abstract

In this paper results of investigation on concentrated piezoelectric networks with differentconfigurations are presented. They were used for elastic wave generation and acquisition.The elastic wave propagation phenomenon was used for damage localization in thinaluminium panels. This approach utilized the fact that any discontinuities existing instructural elements cause local changes of physical material properties which affect elasticwave propagation. Elastic waves were excited and received using piezoelectric transducernetworks with different element arrangements. The method of transducer placement andthe number of piezoelectric elements used had an influence on the accuracy of the damagelocalization algorithm. Obviously, the more elements there were, the more data had to beprocessed. After the acquisition process signal processing was conducted in order tocreate damage influence maps. These maps presents elastic wave energy connectedwith reflection from discontinuities. In order to create such a map a computerprogram was developed that assigns a mesh of points to the panel surface. Ateach point the energy of elastic wave reflection was calculated. This energy wasextracted from the acquired signals. This paper summarizes an extensive experimentalinvestigation that included three damage scenarios and twelve transducer configurations.