Comparative Study of Laser Doppler Vibrometer and Capacitive Air‐coupled Transducer for Ultrasonic Propagation Imager and the New Development of an Efficient Ultrasonic Wavenumber Imaging Algorithm

Truong, Chung Thanh; Kang, Dong Hoon; Lee, Jung-Ryul; Farrar, Charles R.

doi:10.1111/str.12144

Cited by 31 publications

(26 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The full wavefield detection technology can effectively detect delamination [13], fatigue cracks [14] and notches [15], relying on the collection of large amounts of information. The wavefield is generally acquired by point-by-point measurement devices such as the scanning laser Doppler vibrometer (SLDV) [16]. The main limitation of wavefield-based acquisition process is generally time-consuming.…”

Section: Introductionmentioning

confidence: 99%

Sparse Reconstruction and Damage Imaging Method Based on Uniform Sparse Sampling

Luo

Feng

et al. 2020

Acta Mech. Solida Sin.

View full text Add to dashboard Cite

The full wavefield detection method based on guided waves can efficiently detect and locate damages relying on the collection of large amounts of wavefield data. The acquisition process by scanning laser Doppler vibrometer (SLDV) is generally time-consuming, which is limited by Nyquist sampling theorem. To reduce the acquisition time, full wavefield data can be reconstructed from a small number of random sampling point signals combining with compressed sensing. However, the random sampling point signals need to be obtained by adding additional components to the SLDV system or offline processing. Because the random sparse sampling is difficult to achieve via the SLDV system, a new uniform sparse sampling strategy is proposed in this paper. By using the uniform sparse sampling coordinates instead of the random spatial sampling point coordinates, sparse sampling can be applied to SLDV without adding additional components or offline processing. The simulation and experimental results show that the proposed strategy can reduce the measurement locations required for accurate signal recovery to less than 90% of the Nyquist sampling grid, and the damage location error is within the minimum half wavelength. Compared with the conventional jittered sampling strategy, the proposed sampling strategy can directly reduce the sampling time of the SLDV system by more than 90% without adding additional components and achieve the same accuracy of guided wavefield reconstruction and damage location as the jittered sampling strategy. The research results can greatly improve the efficiency of damage detection technology based on wavefield analysis.

show abstract

Section: Introductionmentioning

confidence: 99%

Sparse Reconstruction and Damage Imaging Method Based on Uniform Sparse Sampling

Luo

Feng

et al. 2020

Acta Mech. Solida Sin.

View full text Add to dashboard Cite

show abstract

“…The same method was called Ultrasonic Wavenumber Imaging (UWI) in the UPI system. Several applications of the wavenumber spectroscopy and algorithm modification can be found in the inspection of layer-by-layer 3D-printed parts 28,29 and composite and pipe structures. 28,30…”

Section: Introductionmentioning

confidence: 99%

“…In detail, a novel theoretical study is presented to optimize two essential input parameters of the UWI algorithm (Lamb wave mode and frequency), which previously was only chosen empirically. 27,28 This proposed technique is based on a sensitivity analysis of the spectroscopic wavenumber with respect to a change in thickness. Finally, an inverse method is proposed to estimate the thickness of the structure based on the UWI map.…”

Section: Introductionmentioning

confidence: 99%

Thickness reconstruction of nuclear power plant pipes with flow-accelerated corrosion damage using laser ultrasonic wavenumber imaging

Truong

Lee

2017

Structural Health Monitoring

View full text Add to dashboard Cite

The pipeline is an essential part of nuclear and other power plants. Designed to operate for decades, the pipeline is susceptible to multiple types of damage due to working in a high pressure, high temperature, and highly corrosive environment. Therefore, it requires regular inspection. The issue of many current nondestructive testing systems for pipelines is the use of a one-dimensional scan mechanism along the longitudinal direction of the pipe, which is incompatible with the two-dimensional curvature of elbow pipes, yet it is at these places in which the flow changes directions inside the elbow pipes that a common type of damage occurs: flow-accelerated corrosion damage. In this article, flow-accelerated corrosion damage is visualized using the Ultrasonic Wavenumber Imaging algorithm, which maps the dominant local spectroscopic wavenumber of the wavefield at a particular mode and a particular frequency. In previous studies, the mode and frequency were chosen empirically. In this article, a novel theoretical study is presented to optimize the two input parameters of Ultrasonic Wavenumber Imaging based on a sensitivity analysis of the spectroscopic wavenumber with respect to the change in thickness of the structural base. Additionally, an inverse method is proposed to estimate the thickness of the structure based on the Ultrasonic Wavenumber Imaging map.

show abstract

“…This issue can be overcome using economical non-contact sensors, such as the classical SHM/NDE method that depends mostly on actuators and piezoelectric (PZT) sensors [2,3]. Such method can be used to measure wave signals to detect damage using installed PZT sensors [4,5,6,7,8], which are inexpensive.…”

Section: Introductionmentioning

confidence: 99%

A Visualization Method for Corrosion Damage on Aluminum Plates Using an Nd:YAG Pulsed Laser Scanning System

Lee

Zhang

Lee

et al. 2016

Sensors

View full text Add to dashboard Cite

This paper proposes a non-contact nondestructive evaluation (NDE) technique that uses laser-induced ultrasonic waves to visualize corrosion damage in aluminum alloy plate structures. The non-contact, pulsed-laser ultrasonic measurement system generates ultrasonic waves using a galvanometer-based Q-switched Nd:YAG laser and measures the ultrasonic waves using a piezoelectric (PZT) sensor. During scanning, a wavefield can be acquired by changing the excitation location of the laser point and measuring waves using the PZT sensor. The corrosion damage can be detected in the wavefield snapshots using the scattering characteristics of the waves that encounter corrosion. The structural damage is visualized by calculating the logarithmic values of the root mean square (RMS), with a weighting parameter to compensate for the attenuation caused by geometrical spreading and dispersion of the waves. An intact specimen is used to conduct a comparison with corrosion at different depths and sizes in other specimens. Both sides of the plate are scanned with the same scanning area to observe the effect of the location where corrosion has formed. The results show that the damage can be successfully visualized for almost all cases using the RMS-based functions, whether it formed on the front or back side. Also, the system is confirmed to have distinguished corroded areas at different depths.

show abstract

Comparative Study of Laser Doppler Vibrometer and Capacitive Air‐coupled Transducer for Ultrasonic Propagation Imager and the New Development of an Efficient Ultrasonic Wavenumber Imaging Algorithm

Cited by 31 publications

References 23 publications

Sparse Reconstruction and Damage Imaging Method Based on Uniform Sparse Sampling

Sparse Reconstruction and Damage Imaging Method Based on Uniform Sparse Sampling

Thickness reconstruction of nuclear power plant pipes with flow-accelerated corrosion damage using laser ultrasonic wavenumber imaging

A Visualization Method for Corrosion Damage on Aluminum Plates Using an Nd:YAG Pulsed Laser Scanning System

Contact Info

Product

Resources

About