Research on Automatic Control Algorithm for High-Precision Electrostatic Tuning of Micro Hemisphere Resonant Gyroscope

Based on the electrostatic tuning theory model of micro hemisphere resonant gyroscope (MHRG) with frequency split, explores the variation law of frequency split with tuning voltage, formulates electrostatic tuning steps. In order to achieve automation of MHRG electrostatic tuning, this article proposes a tuning scheme using phase-locked loop (PLL) and mode switching, and deeply analyzes different control algorithms: function fitting, PID control, and dichotomy of effective interval of electrostatic tuning voltage’s square (EIETVS). Based on the established automatic electrostatic tuning device, experiments have verified that all three control algorithms can complete the electrostatic tuning of MHRG and achieve high-precision mode matching. Specifically, by applying two control algorithms, PID control and the dichotomy of EIETVS, the frequency split of the gyroscope after tuning can achieve an accuracy of less than 1 mHz. By comparing and analyzing the characteristics of three control algorithms, it can be concluded that the dichotomy of EIETVS proposed in this article based on the idea of substitution is more practical and has certain application prospects and value in the field of electrostatic tuning of resonant gyroscopes.