Dynamic Characteristic Modeling and Simulation for a Fiber-optic Gyroscope Integration System

Abstract

Fiber-optic gyroscopes (FOGs) are widely applied because they have several advantages such as simple structure, no moving components, short initiation time, and high sensitivity. FOGs can indicted heading, altitude, position, speed, and acceleration accurately and are thus useful in navigation and aviation. Transmission errors resulting from mechanical vibration of the carrier and structural resonance prevent FOGs from displaying precise positioning during inertial navigation. This study used the experimental modal analysis to conduct sinewave sweeps to measure the natural frequency and amplitude of FOGs when vibrated by external forces. Output signal deviations were observed when the structure reached the resonance frequency. Moreover, random vibrations were induced to simulate the flight vibrational environment, and the output signals were recorded before and after the vibration. Finally, the finite element analysis (FEA) was used to simulate each condition to obtain the structural nature frequency in the vibration experiment. The FEA simulation results were compared with those from the experiments to validate the differences; these results could serve as references for future structural designs and modifications. Furthermore, the comparison improves the signal transmission deviation with structural resonance and provides precision FOG navigations.