Effects of Normal-Distributed Measurement Error on Frequency Tuning for a Cylindrical Vibratory Gyroscopes

Cylindrical vibratory gyroscope is a kind of mode-matched gyros, and the frequency split would affect its sensitivity significantly. Frequency tuning is a major method to decrease the split. In the process of frequency tuning, the natural frequency should be measured firstly, and the measurement error is one of the decisive factor of tuning accuracy. Due to the measurement error of frequency is Normal Distribution, its effects on frequency tuning are studied by theoretical and simulation analysis from the statistical aspect. Firstly, the influence of frequency splitting on gyro sensitivity is studied, which shows the importance of reducing frequency splitting. Then the effect of different measuring accuracy on the measured value is analyzed. Thirdly, the tuning error that caused by the measurement error is researched in the process of trimming, and the tuning error is derived by theoretical analysis. Simulation and experiment results under different measurement error exemplify the value of tuning error. Finally, the optimal measurement accuracy that ensures achieving tuning accuracy is discussed.