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Traditional structural damage detection methods in aerospace applications face challenges in accuracy and sensitivity, often necessitating multiple sensors to evaluate various measurement paths between the reference and defective states. However, the recently developed topological acoustic (TA) sensing technique can capture shifts in the geometric phase of an acoustic field, enabling the detection of even minor perturbations in the supporting medium. In this study, a diagnostic imaging method for damage detection in plate structures based on the TA sensing technique is presented. The method extracts the geometric phase shift index (GPS-I) from the Lamb wave response signals to indicate the location of the damage. Using Abaqus/CAE, a finite element model of the plate was established to simulate the Lamb wave response signals, which were then used to validate the feasibility of the proposed method. The results indicate that this technique enables rapid and precise identification of damage and its location within the plate structure, requiring response signals from only a few points on the damaged plate, and it is reference-free.
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This content will become publicly available on November 1, 2026
Geometric Phase Sensing Using Cross-Correlations for Structural Anomaly Detection Under Broadband and Stochastic Excitations
Abstract This study demonstrates a novel nondestructive evaluation (NDE) method that combines geometric phase sensing with cross-correlation processed acoustical responses, enabling the detection of structural anomalies even when the acoustic excitation is stochastic and the source characteristics are variable. Traditional ultrasonic techniques, which depend on impulse responses from known source locations to capture wave transmission behavior, often fail under stochastic excitations due to incoherent phase alignment and unpredictable wave paths. The proposed method applies cross-correlation between a fixed reference site and other sensor locations to refine the acoustic field representation, enabling physically meaningful geometric phase extraction through the dot product of two state vectors representative of the acoustic field in a high-dimensional complex Hilbert space. This allows detection of both excitation-induced field asymmetries and subtle nonlinearities. Experimental validation using laser Doppler vibrometry on a circular IN625 plate demonstrates that this approach preserves excitation-induced field asymmetries while remaining sensitive to structural perturbations such as mass defects. The cross-correlation geometric phase change (CC-Δφ) spectra reveal modal differences across excitation conditions, even under white noise, where geometric phase without cross-correlation (Δφ) remains centered near 90 deg, obscuring structural insights. The method also detects mass-induced effects, showing increased average CC-Δφ compared to the no-mass case under the same excitation condition. These results establish a foundation for a robust, non-contact, source-independent NDE technique, suitable for operation under variable and uncontrolled excitation scenarios.
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- Award ID(s):
- 2242925
- PAR ID:
- 10689970
- Publisher / Repository:
- ASME
- Date Published:
- Journal Name:
- Journal of Nondestructive Evaluation, Diagnostics and Prognostics of Engineering Systems
- Volume:
- 8
- Issue:
- 4
- ISSN:
- 2572-3901
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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