# Research on Piezoelectric Guided Wave Frequency Diverse Array-Based Damage Location Method for Thin-Walled Structures

## TL;DR

This paper introduces a new method for locating damage in thin-walled structures using frequency diverse arrays and guided waves, improving accuracy and efficiency.

## Contribution

A novel guided wave frequency diverse array method for two-dimensional damage localization in thin-walled structures is proposed.

## Key findings

- The frequency diverse array model enables two-dimensional focusing for damage detection.
- Three receiving array configurations were tested to maximize signal amplitude from damage.
- Simulations and experiments confirmed the method's validity on aluminum and epoxy plates.

## Abstract

Phased array technology can be realized with directional control with fixed beam steering. However, its directionally dependent beam pattern limits the efficiency of suppressing undesirable distance interference. This paper presents a guided wave frequency diverse array-based damage location method for thin-walled structures. Firstly, a guided wave frequency diverse array signal model is derived with a relatively small frequency increment that can achieve distance–direction two-dimensional focusing. Secondly, three types of receiving arrays, including a monostatic array, following array, and symmetric array, are constructed to achieve the maximum damage-induced signal amplitude. Finally, a two-dimensional multiple signal classification (MUSIC)-based damage location method is applied for damage imaging in thin-walled structures. Simulations on an aluminum plate and the experiments on an epoxy laminate plate demonstrate the validity and effectiveness of the proposed method.