Localization of low velocity impact on CFRP laminate using normalized error outlier-based algorithm cooperating with Db3-wavelet threshold noise reduction and FBG sensors

Abstract

This study conducted the localization of low velocity impact on Carbon Fiber Reinforced Plastic (CFRP) laminate using a normalized error outlier-based algorithm cooperating with Daubechies3 (Db3)-wavelet threshold noise reduction. The monitoring of CFRP plate impact was conducted by multiplex Fiber Bragg Grating (FBG) sensors connected to its upper surface, and the impact response signal was collected using an interrogator at a frequency of 2 kHz. Results showed that the Db3-wavelet threshold noise reduction algorithm could improve the impact localization performance of CFRP plate structure. By setting an appropriate outlier threshold and using a normalized error outlier-based algorithm, the low velocity impact on CFRP plate was successfully located with a maximum localization error of 21.35 mm and an average localization error of 8.19 mm.