Rate Integrating Hemispherical Resonator Gyroscope Detection Error Analysis and Compensation

Compensation for the hemispherical resonator gyroscope (HRG) detection error significantly improves gyroscope performance as well as provides a basis for the implementation of high-precision control algorithms. In this article, an identification method is proposed in which the precession factor and the detection error parameters, including gain error, nonorthogonal angle error, and phase error, can be identified simultaneously in a single test. First, we analyze the detection error caused by gyroscope manufacturing as well as the inconsistency in circuit device parameters. Second, the detection error is modeled, and the impact of the error on the standing wave azimuth detection and the control system is discussed. Third, a method is presented for identifying the error parameters based on the nonlinear least squares. Finally, experiments are conducted to verify the effectiveness of the identification and compensation method. As a result of compensation, the bias instability decreases by 33 times from 5.08 degrees/h to 0.15 degrees/h, and the scale factor nonlinearity decreases by four times from 50.26 to 10.23 ppm.