Full-field ultrasonic inspection for a composite sandwich plate skin-core debonding detection using laser-based ultrasonics

In this paper, a full-field ultrasonic guided wave method is proposed to inspect a composite sandwich specimen made for an aircraft engine nacelle. The back skin/core interface of the specimen is built with two fabricated disbond defects (diameters of 12.7 mm and 25.4 mm) by removing areas of the adhesive used to bond the back skin to the core. A laser ultrasonic interrogation system (LUIS) incorporated with a disbond detection algorithm is developed. The system consists of a 1-kHz laser ultrasonic scanning system and a single fixed ultrasonic sensor to interrogate ultrasonic guided waves in the sandwich specimen. The interest area of 400 mm × 400 mm is scanned at a 0.5 mm scan interval. The corresponding full-field ultrasonic data is obtained and generated in the three-dimensional (3-D) space-time domain. Then, the 3-D full-field ultrasonic data is Fourier transformed and the ultrasonic frequency spectra are analyzed to determine the dominant frequency that is sensitive to the disbond defects. Continuous wavelet transform (CWT) based on fast Fourier transform (FFT) is implemented as a single-frequency bandpass filter to filter the full-field ultrasonic data in the 3-D space-time domain at the selected dominant frequency. The LUIS has shown the ability to detect the disbond with diameters of 11 mm and 23 mm which match to the pre-determined disbond sizes well. For future research, a robust signal processing algorithm and a model-based matched filter will be investigated to make the detection process autonomous and improve detectability

[1]  Constantinos Soutis,et al.  Lamb waves for the non-destructive inspection of monolithic and sandwich composite beams , 2005 .

[2]  Nobuo Takeda,et al.  Smart Composite Sandwich Structures for Future Aerospace Application -Damage Detection and Suppression-: a Review , 2007 .

[3]  Emmanuel Moulin,et al.  Radome health monitoring with Lamb waves: experimental approach , 2000 .

[4]  Jung‐Ryul Lee,et al.  Dual-energy wave subtraction imaging for damage detection in ultrasonic propagation imaging system , 2016, 2016 IEEE Aerospace Conference.

[5]  Junji Takatsubo,et al.  Generation Laser Scanning Method for the Visualization of Ultrasounds Propagating on a 3-D Object with an Arbitrary Shape , 2006 .

[6]  D. Roy Mahapatra,et al.  Guided wave based detection of damage in honeycomb core sandwich structures , 2012 .

[7]  Victor Giurgiutiu,et al.  Embedded non-destructive evaluation for structural health monitoring, damage detection, and failure prevention , 2005 .

[8]  Guoliang Huang,et al.  Guided wave propagation in honeycomb sandwich structures using a piezoelectric actuator/sensor system , 2009 .

[9]  K. K. Sharma,et al.  Power line interference removal from ECG signals using wavelet transform based component-retrieval , 2016, 2016 International Conference on Advances in Computing, Communications and Informatics (ICACCI).

[10]  Samir Mustapha,et al.  Leaky and non-leaky behaviours of guided waves in CF/EP sandwich structures , 2014 .

[11]  Liang-chuan Li.  A New Method of Wavelet Transform Based on FFT for Signal Processing , 2010, 2010 Second WRI Global Congress on Intelligent Systems.

[12]  J. C. Ma,et al.  A FILTER DESIGN METHOD BASED ON COMBINATION WAVELETS , 1997 .

[13]  Lingyu Yu,et al.  Study of Guided Wave Propagation in Honeycomb Sandwich Structures , 2014 .

[14]  L. Drain,et al.  Laser Ultrasonics Techniques and Applications , 1990 .

[15]  Jan Drewes Achenbach,et al.  Quantitative nondestructive evaluation , 2000 .

[16]  E. Flynn,et al.  Remote imaging of local resonance for inspection of honeycomb sandwich composite panels , 2015, 2015 IEEE SENSORS.

[17]  J. Rose.  Ultrasonic Waves in Solid Media , 1999 .

[18]  Colum D. MacKinnon,et al.  Time–frequency analysis of movement-related spectral power in EEG during repetitive movements: A comparison of methods , 2010, Journal of Neuroscience Methods.

[19]  Dariusz Komorowski,et al.  The Use of Continuous Wavelet Transform Based on the Fast Fourier Transform in the Analysis of Multi-channel Electrogastrography Recordings , 2015, Journal of Medical Systems.

[20]  Jung-Ryul Lee,et al.  Radome health management based on synthesized impact detection, laser ultrasonic spectral imaging, and wavelet-transformed ultrasonic propagation imaging methods , 2012 .

[21]  Will Mitchell,et al.  Wavenumber study of guided waves in aluminum honeycomb sandwich structures , 2015, Smart Structures.

[22]  Jean-Michel Poggi,et al.  Wavelet Toolbox User s Guide , 1996 .

[23]  Hoon Sohn,et al.  Time reversal active sensing for health monitoring of a composite plate , 2007 .

[24]  Carlos E. S. Cesnik,et al.  Review of guided-wave structural health monitoring , 2007 .

[25]  Fabrizio Scarpa,et al.  Structural health monitoring using scanning laser vibrometry: I. Lamb wave sensing , 2004 .

[26]  Jung-Ryul Lee,et al.  Repeat scanning technology for laser ultrasonic propagation imaging , 2013 .

[27]  Tadeusz Uhl,et al.  Identification of modal parameters of non-stationary systems with the use of wavelet based adaptive filtering , 2014 .

[28]  Gengkai Hu,et al.  Online Guided Wave-Based Debonding Detection in Honeycomb Sandwich Structures , 2012 .