Identification of Added Mass in the Composite Plate Structure Based on Wavelet Packet Transform

Abstract

A new concept has been introduced that the combination of rotational mode shape with two‐dimensional wavelet packet transform to detect the added mass (damage) in a glass fibre reinforced polymer composite plate structure. Wavelet packet transform is an advanced signal processing tool that can magnify the abnormality features in the signal. Rotational mode shapes are sensitive to damage in beam and plate structures. The proposed method employs an added mass, which slides to different locations to alter the local and global dynamic characteristics of the structure. Finite element analysis is carried out to obtain the first three rotational bending mode shapes, from the damaged plate structure, then used as input to two‐dimensional wavelet packet transform. The numerical results of normalised diagonal detail wavelet packet coefficients show a peak at single or multiple added mass (damage) locations of a plate structure for two different boundary conditions. This method seems to be sensitive to relatively small amount of damage to the plate structure. A simple parametric study is carried out for the damage extent quantification. In addition, investigation with noise‐contaminated signals shows its feasibility in the real applications.

Point mass identification in rectangular plates from minimal natural frequency data

“…The extension of the method to composite plates is another challenging issue that could be investigated. In this regard, it should be mentioned the recent contribution by Rajendran and Srinivasan [13] on the identification of an added mass in a glass fibre reinforced polymer composite plate by using a combination of rotational mode shape information with wavelet transform analysis.…”

Damage Identification Based on Adding Mass for Liquid–Solid Coupling Structures

“…Dinh et al [24] identified the mass, damping coefficient, and stiffness of structures based on the correlation between the structural modal information and additional masses. Rajendran et al [25] attached a mass to different locations of a composite plate structure to change the dynamic characteristics. This allowed us to obtain the rotational bending mode shapes to identify damage.…”

Data encoding and reconstruction of thermal imaging maps of impact damaged composite Structures using feature space and neural networks

“…Such effects results from impact damage and would change certain features in the testing image of a damaged sample compared to the one before impact. The new captured image will display a pattern which differ from a reference image texture, color or intensity, among others and can be used to establish level and magnitude of damage and component validity as a function of feature distribution change [15][16][17][18][19][20][21][22][23].…”