Segmentation of Hidden Delaminations with Pitch–Catch Ultrasonic Testing and Agglomerative Clustering

This paper studies the detection of hidden polymer matrix composite delaminations with a pitch–catch ultrasonic testing system and an agglomerative clustering algorithm. Existing ultrasonic testing methods characterize damage through normal-incidence pulse-echo measurements. Yet, these pulse-echo methods are ineffective at detecting delaminations underneath other delaminations. The ultrasonic waves only reflect off the top delamination. As a...