Compensation for temperature-dependent phase and velocity of guided wave signals in baseline subtraction for structural health monitoring
File(s)
Accepted version
Author(s)
Mariani, S
Heinlein, S
Cawley, P
Type
Journal Article
Abstract
Baseline subtraction is commonly used in guided wave structural health monitoring to identify the signal changes produced by defects. However, before subtracting the current signal from the baseline, it is essential to compensate for changes in environmental conditions such as temperature between the two readings. This is often done via the baseline stretch method that seeks to compensate for wave velocity changes with temperature. However, the phase of the signal generated by the transduction system is also commonly temperature sensitive and this effect is neglected in the usual compensation procedure. This article presents a new compensation procedure that deals with both velocity and phase changes. The results with this new method have been compared with those obtained using the standard baseline stretch technique on both a set of experimental signals and a series of synthetic signals with different coherent noise levels, feature reflections, and defect sizes, the range of noise levels and phase changes being chosen based on initial experiments and prior field experience. It has been shown that the new method both reduces the residual signal from a set baseline and enables better defect detection performance than the conventional baseline signal stretch method under all conditions examined, the improvement increasing with the size of the temperature and phase differences encountered. For example, in the experimental data, the new method roughly halved the residual between baseline and current signals when the two signals were acquired at temperatures 15°C apart.
Date Issued
2020-01-01
Date Acceptance
2019-03-01
Citation
Structural Health Monitoring: an international journal, 2020, 19 (1), pp.26-47
ISSN
1475-9217
Publisher
SAGE Publications
Start Page
26
End Page
47
Journal / Book Title
Structural Health Monitoring: an international journal
Volume
19
Issue
1
Copyright Statement
© The Author(s) 2019. . The final, definitive version of this paper has been published in Structural Health Monitoring by Sage Publications Ltd. All rights reserved. It is available at: https://journals.sagepub.com/doi/10.1177/1475921719835155
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Grant Number
EP/L022125/1
Subjects
Science & Technology
Technology
Engineering, Multidisciplinary
Instruments & Instrumentation
Engineering
Temperature compensation
phase compensation
structural health monitoring
guided waves
ultrasound
receiver-operating characteristic curves
baseline subtraction
signal stretch method
torsional waves
pipe inspection
STRATEGIES
VALIDATION
SYSTEM
Acoustics
09 Engineering
Publication Status
Published
Date Publish Online
2019-03-14