Multiple Signal Classification-Based Impact Localization in Composite Structures Using Optimized Ensemble Empirical Mode Decomposition

Abstract

Multiple signal classification (MUSIC) algorithm-based structural health monitoring technology is a promising method because of its directional scanning ability and easy arrangement of the sensor array. However, in previous MUSIC-based impact location methods, the narrowband signals at a particular central frequency had to be extracted from the wideband Lamb waves induced by each impact using a wavelet transform. Additionally, the specific center frequency had to be obtained after carefully analyzing the impact signal, which is time consuming. Aiming at solving this problem, this paper presents an improved approach that combines the optimized ensemble empirical mode decomposition (EEMD) and two-dimensional multiple signal classification (2D-MUSIC) algorithm for real-time impact localization on composite structures. Firstly, the impact signal at an unknown position is obtained using a unified linear sensor array. Secondly, the fast Hilbert Huang transform (HHT) with an optimized EEMD algorithm is introduced to extract intrinsic mode functions (IMFs) from impact signals. Then, all IMFs in the whole frequency domain are directly used as the input vector of the 2D-MUSIC model separately to locate the impact source. Experimental data collected from a cross-ply glass fiber reinforced composite plate are used to validate the proposed approach. The results show that the use of optimized EEMD and 2D-MUSIC is suitable for real-time impact localization of composite structures.

Ultrasonic Guided-Waves Sensors and Integrated Structural Health Monitoring Systems for Impact Detection and Localization: A Review

“…New developments that are based on the MUSIC algorithm have been proposed for impact energy estimation [ 42 ] and for the direction of arrival of a Lamb wave [ 43 ]. The computational efficiency is also important for real-time systems and Zhong et al proposed an improvement in the processing scheme [ 44 ].…”

Structural Health Monitoring of Large Structures Using Acoustic Emission–Case Histories

“…While this produced improvements, some real effects like damage-induced velocity variation still needs additional study, as noted by the authors. Zhong et al [17] provided another approach for improving source location accuracy. This is called multiple signal classification (MUSIC), which adds directional scanning ability and easy arrangement of the sensor array.…”

Frequency Aliasing-Based Spatial-Wavenumber Filter for Online Damage Monitoring

“…In the existing SHM technologies, the damage imaging method which has high signal-to-noise ratio can visually indicate damage location and size. Examples of these imaging techniques include the delay-and-sum method [6][7][8][9], time reversal method [10][11][12][13], probabilistic diagnostic algorithm [14][15][16][17], phased array method [18][19][20][21], multisignal classification method [22][23][24][25][26], and spatial-wavenumber filter method [27][28][29][30][31][32][33][34][35]. Among them, the spatial-wavenumber filter method, which has been extensively studied, can extract the specific mode of the Lamb wave, distinguish the incident wave and damage scattering wave, and reduce the overlap of Lamb wave signals [33][34][35].…”