A Compressive Sensing-Based Ultrasonic Guided Wave Field Damage Detection Method Applicable to Plate Structures

Abstract

The invention discloses a compressive sensing-based ultrasonic guided wave field damage detection method suitable for plate structures, the steps of which include: constructing an SLDV sampling system; determining space sparse sampling grid coordinates, inputting the sampling coordinates into the SLDV sampling system, respectively Collect ultrasonic guided wave signals in the healthy state and the damaged state, and subtract the two sets of signals to obtain the difference signal containing the damage scattering information; randomly estimate the position of the damage scattering source to obtain the assumed source coordinates; establish the compressed sensing equation , and use the basis tracking denoising algorithm to solve the excitation function of the hypothetical source; use the obtained excitation function to reconstruct the full wave field, and perform RMS imaging on the reconstructed full wave field to obtain the damage imaging result. The present invention applies compressed sensing technology to the field of ultrasonic guided wave field damage detection, utilizes spatially regularly distributed sparse sampling signals for wave field reconstruction and damage imaging, can reduce the measurement time for obtaining the full wave field by more than 90%, and simultaneously obtains The reconstructed wavefield has a coherence coefficient close to 0.8 with the full measured wavefield.

Description

technical field [0001] The invention belongs to the technical field of nondestructive testing, and in particular relates to a compressive sensing-based ultrasonic guided wave field damage testing method suitable for plate structures. Background technique [0002] As a common structural form, plate structure has been widely used in aerospace, transportation, petroleum engineering and other fields. During the long-term service, the thin-plate structure will be affected by factors such as load and environment, and different degrees of structural damage will occur. Therefore, the safety detection of such structures not only helps to prevent safety accidents, but also avoids unnecessary economic losses. [0003] At present, the traditional non-destructive testing methods suitable for plate structures mainly include: magnetic flux leakage testing, ultrasonic C-scanning, penetration and acoustic emission testing, etc. Among them, although magnetic flux leakage detection and ultra...

AI Technical Summary

Problems solved by technology

Recently, some scholars have proposed a method based on compressed sensing to sparsely reconstruct the full wave field. However, the method requires random sampling in space, and commercial SLDV systems require additional components to support random measurements, so it is difficult to implement this method.

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