Identification and correction of phase delay errors for hemispherical resonator gyroscopes.

Area of Science:

• Inertial Navigation Systems
• Sensor Technology
• Precision Measurement

Background:

• Phase-delay error is the main cause of output error in hemispherical resonator gyroscopes (HRGs).
• Temperature variations exacerbate phase-delay error, degrading gyroscope calibration and performance.

Purpose of the Study:

• To propose and validate a self-calibration method for mitigating phase-delay error in HRGs.
• To enhance the real-world application performance and temperature robustness of gyroscopes.

Main Methods:

• Introduced a sinusoidal interference signal into the quadrature control loop of a whole-angle mode HRG.
• Demodulated the angular rate signal to calculate phase-delay error.
• Utilized the calculated error as a compensation value for the Phase-Locked Loop (PLL) reference phase.

Main Results:

• Self-calibration reduced the gyroscope's zero-bias output error by five times.
• Bias instability improved by 37.7% after implementing the self-calibration method.
• The proposed method demonstrated enhanced robustness against temperature fluctuations.

Conclusions:

• The developed self-calibration technique effectively suppresses phase-delay error in HRGs.
• This method significantly improves gyroscope accuracy, stability, and temperature resilience.