Data-Driven Temperature Compensation on Lamb Waves

Abstract

Active guided-wave-based structural health monitoring techniques have been widely studied for inspecting civil, aerospace and maritime structures. The vast majority of such methods estimate the change in the structures between the times a baseline measurement and the test measurements were made. Temperature changes between baseline and test signal acquisition affects the propagation of the wave in nonlinear and mode-dependent ways. As a result, baseline comparison methods fail when the test and baseline signals are collected at different temperatures. In this paper, we present a novel temperature compensation algorithm that corrects for temperature effects separately for different modes of propagation. Results of experimental data analysis demonstrating that the the method of this paper substantially outperforms the commonly employed baseline signal stretch algorithm are also presented.