Impact localization in composite using multiple signal classification method

In order to improve accuracy and real-time of impact localization in composite, the array signal processing technique was introduced into the area of structure health monitoring and a new method for impact monitoring in composite was proposed based on the wavelet transform and multiple signal classification (MUSIC) method. Firstly, narrowband frequency components of response signals were extracted by using wavelet transform, followed by the estimation of the direction-of-arrival (DOA) based on MUSIC method. Secondly, based on the propagation characteristics of lamb wave, the time-delay between symmetry and antisymmetry modal waves of one central frequency lamb wave arriving to the same array element was gained by using the wavelet transform, and the distance between impact source and array element was estimated according to velocity difference between symmetry and antisymmetry modal waves, thus the impact localization was realized. Experiments on the laminated glass fiber reinforced epoxy composite and laminated carbon fiber reinforced bismaleimide composite indicate that the present methodology can identify the impact location fast and accurately.