Dynamic amplitude frequency characteristic of GMM based on optical fiber measurement technique

Abstract

A FBG-GMM dynamic strain measurement setup with ferromagnetic circuit was established based on the magnetostriction characteristic of Giant magnetostrictive material (GMM) and the susceptibility of fiber Bragg grating (FBG) to strain. This system was constructed using the FBG dynamic strain demodulating scheme of optical filter linear sideband. The finite element analysis and experimental result show that the dynamic output of the GMM does not change with the frequency in the range of 50∼1000Hz and the GMM can be used in dynamic measurement of low-frequency signal.