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Updated: Jul 16, 2026
10:52
Conducting Elevated Temperature Normal and Combined Pressure-Shear Plate Impact Experiments Via a Breech-end Sabot Heater System
Published on: August 7, 2018
Acoustic impact localization in plates: properties and stability to temperature variation
Guillemette Ribay1, Stefan Catheline, Dominique Clorennec
1Laboratoire Ondes et Acoustique, ESPCI, Paris, France. guillemette.ribay@loa.espci.fr
Summary
This study demonstrates acoustic time reversal for impact localization on plates using a single accelerometer. The technique effectively compensates for temperature variations, enabling reliable outdoor applications.
Area of Science:
- Acoustics
- Solid Mechanics
- Wave Propagation
Background:
- Impact localization on plate-shaped objects is crucial for structural health monitoring.
- Acoustic time reversal offers a promising non-destructive method for signal focusing and localization.
- Understanding wave propagation, including Lamb modes and evanescent waves, is key to refining localization accuracy.
Purpose of the Study:
- To investigate the feasibility of impact localization on plate-shaped solids using acoustic time reversal.
- To analyze the nature of acoustic waves generated by impacts and their propagation characteristics.
- To develop a method for compensating temperature-induced variations in acoustic signatures for robust localization.
Main Methods:
- Experimental acoustic time reversal with a single accelerometer.
- Two-dimensional (2-D) elastic wave propagation simulation.
- Heterodyne interferometry for measuring impulse responses during temperature changes.
Main Results:
- Acoustic time reversal successfully localized impacts on plate-shaped objects.
- The A0 Lamb mode was identified as the primary propagating wave, with evanescent waves significant near edges.
- Impact distinction improved with decreased plate thickness and increased frequency.
- A compensation algorithm effectively mitigated temperature effects on acoustic signatures.
Conclusions:
- Single-accelerometer acoustic time reversal is effective for impact localization.
- Evanescent wave considerations are important for precise localization near plate edges.
- Temperature compensation algorithms enhance the reliability of acoustic time reversal for real-world applications, including outdoor use.
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