Research on dynamic performance evaluation of fiber optic gyroscope based on laser Doppler measurement technology

Abstract

The bandwidth of the fiber optic gyroscope is an important indicator of its frequency characteristics. When the environmental conditions is under high dynamic such as vibration and sharp turns, the measurement accuracy of fiber optic gyroscope is greatly affected due to the limitation of the frequency characteristics of fiber optic gyroscopes. And the traditional bandwidth measurement method is to record the angular vibration’s amplitude and frequency of the turntable and the output of fiber optic gyroscope, and then use the least squares method to obtain the bandwidth of fiber optic gyroscope. However, the output frequency of the turntable’s circular grating encoder is not high enough, usually less than 100Hz, which cannot reflect the more comprehensive dynamic performance of the fiber optic gyroscope. And the manual operation test is always cumbersome. All of these limits the further research on the dynamic performance of fiber optic gyroscope. Therefore, this paper proposes a fiber optic gyroscope bandwidth evaluation method based on laser Doppler measurement technology. Then, an adaptive modal decomposition algorithm is proposed, which can adaptively decompose complex nonlinear and non-stationary signals into multiple frequency components. Our system can realize high-frequency, high-precision and non-contact, which is of great significance to the research of the dynamic performance of the fiber optic gyroscope.