Localization of low-velocity impact on a composite honeycomb sandwich structure
Zhao Lin-hu; Zhou Li
MOE Key Lab of Structure Mechanics and Control for Aircraft; Institute of Structures & Strength; Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
Abstract:Low-velocity impact tests are performed on a carbon fiber reinforced composite honeycomb sandwich structure, and a localization method using stress wave and immune genetic algorithms (IGA) is used to analyze and locate the low-velocity impact on this composite structure. First, after obtaining a set of impact-induced stress wave signals from pre-determined impact tests, wavelet transform is applied to analyze these stress wave signals in the time-frequency domain to obtain the propagation velocity of the impact-induced stress waves in the composite structure. Then, considering the anisotropic properties of stress wave propagation in composite honeycomb structure, IGA is employed to identify the location of unknown low-velocity impact. Experimental results have demonstrated the applicability and effectiveness of the impact localization method.