Effect of structural material upon the dynamic performance of FOG

In a dynamic process, the fiber-optic gyroscope (FOG) generates a nonreciprocal error easily. After analyzing the reason of the FOG generating dynamic error, the principle that structural material performance has a significant influence on the FOG dynamic performance was proposed. Applied different structural materials in the structural body that as FOG the major part, the finite element models were made respectively. The ratio stiffness of structural material impacting on the FOG dynamic performance was qualitatively analyzed through modal analysis and harmonic response analysis. Random vibration and sine sweep vibration experiments were also executed for confirmation with finite element model. The results show that the first resonance frequency of the FOG is increased from 1 454 Hz to 2 213 Hz by applying beryllium aluminum alloy which has higher ratio stiffness instead of aluminum alloy. FOG dynamic accuracy is significantly improved with the resonance frequency increasing. Deserve to mention that beryllium aluminum alloy makes the FOG become lighter and more suitable for use in a small and light FOG.