Damage Localization in an Aluminum Plate Using Built-In Piezo-electric Sensor Induced Ultrasonic Signals

Abstract

This paper summarizes a study by students taking the class of AA257 Structural Health Monitoring of Spring of 2023 at Stanford University as a term project to predict the location and size of a single crack in an Aluminum plate using ultrasonic waves induced by surface-mounted piezoelectric discs as sensors or actuators. Three methods were presented for determining cracks in the structure, which include: i) calculating the ratio of the raw signals for different paths, ii) evaluating the ratio of the scattered signals for different paths, and iii) determining the damage index for different paths. Of the three methods presented, the second and the third method using the scatter and the damage index, respectively, are the most accurate in locating the crack.