A Method of Dispersion Compensation Based on Warped Frequency Transform

Abstract:

The use of Lamb waves for structural health monitoring (SHM) has complicated by its multi-mode character and dispersion effect, which impacts the damage positioning and high-resolution imaging. The group velocity dispersion curves of Lamb waves can be employed to warp the frequency axis, and then to establish warped frequency transform (WFT) to process Lamb waves. In this paper, received signals are directly compensated with warped frequency transform to suppress dispersion, and a new imaging method is proposed based on warped frequency transform. The propagation of Lamb waves in damaged aluminum plate is simulated by finite element software ABAQUS, results show that warped frequency transform can effectively compensate dispersive wave-packets, and high-resolution damage imaging can be obtained by the proposed method.

• Periodical: Advanced Materials Research (Volumes 718-720)
• Pages: 2062-2067
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.718-720.2062
• Online since: July 2013
• Authors: Shang Chen Fu, Zhen Jian Lv, Ding Ma, Li Hua Shi
• Keywords: ABAQUS, Damage Imaging, Dispersion Compensation, Lamb Wave, Warped Frequency Transform

References

[1] Cai Jian, Yuan Shenfang, Zhang Xiaoyue, Wang Qiang. Lamb wave double side excitation and its application in adjacent damages monitoring [J]. Journal of Nanjing University of Aeronautics & Astronautics,2010,42(1):62-67.

[2] Liu L, Yuan FG. A linear mapping technique for dispersion removal of Lamb waves. Structural Health Monitoring, 2010, 9(1): 75-86.

DOI: 10.1177/1475921709341012

[3] Sicard R, Goyette J and Zellouf D. A numerical dispersion compensation technique for time recompression of Lamb wave signals [J]. Ultrasonics, 2002, 40(1-8): 727-732.

DOI: 10.1016/s0041-624x(02)00201-9

[4] P. Wilcox. A rapid signal processing technique to remove the effect of dispersion from guided wave signals. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2003, 50 (4): 419–427.

DOI: 10.1109/tuffc.2003.1197965

[5] Cai Jian, Shi Lihua, Yuan Shenfang. High spatial resolution imaging for structural health monitoring based on virtual time reversal [J]. Acta Materiae Compositae Sinica, 2012, 29 (1) :183-189.

[6] L. De Marchi, A. Marzani, S. Caporale, and N. Speciale. Ultrasonic guided-waves characterization with warped frequency transforms[J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2009,56(10): 2232–2240.

DOI: 10.1109/tuffc.2009.1305

[7] Luca De Marchi, Massimo Ruzzene, Buli Xu, Emanuele Baravelli, and Nicolò Special. Warped Basis Pursuit for Damage Detection Using Lamb Waves[J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency control, 2010,57,(12):2736-2741.

DOI: 10.1109/tuffc.2010.1747

[8] Wang L, Yuan F G. Damage Identification in a composite plate using prestack reverse-time migration technique [J]. Structural Health Monitoring, 2005, 4(3): 195–211.

DOI: 10.1177/1475921705055233

[9] Michaels J E. Detection, Localization and characterization of damage in plates with an in situ array of spatially distributed ultrasonic sensors [J]. Smart Materials and Structures, 2008, 17(3): 1-15.

DOI: 10.1088/0964-1726/17/3/035035