Applicability of Peak Detection Methods for Composite Fatigue FBG Wavelength

This study compares the accuracy and effectiveness of existing peak detection methods on the FBG spectrum in sensing the fatigue strain in a composite. It aims to give a solution to measure the FBG spectrum and further processing it, including selecting the FBG peak wavelength. The FBG sensor was bonded to the fatigue test specimen and the spectrums were acquired during the fatigue test were progressing. Three different peak detection algorithms were utilised, which include maximum, polynomial and centroid algorithms. Results showed that the centroid has the lowest precision compared to the polynomial and maximum algorithms. For fatigue wavelength data, it was found out that the maximum algorithm and third-order polynomial fitting are applicable as the peak seeking method for fatigue strain data from FBG sensor.