Bias stability and bandwidth enhancement in micro-hemispherical resonant gyroscopes via alternating pseudo-rotation modulation and adaptive proportional–integral (PI) control

Micro-hemispherical resonator gyroscopes (μHRGs) have attracted significant attention in high-end fields such as inertial navigation, aerospace, unmanned aerial vehicles, military equipment, and deep space exploration due to their high precision, low noise, long-term stability, low power consumption, impact resistance, and potential for miniaturization. However, traditional PI control algorithms fail to meet μHRGs' stringent requirements for high bandwidth, low noise, and long-term stability. To address this, an optimized PI closed-loop control system is proposed in this paper. The system implements adaptive tuning of the proportional and integral gain parameters on a Field-Programmable Gate Array (FPGA) platform, enhancing μHRGs' bandwidth from a minimum of 1.5 Hz to over 8 Hz. Additionally, alternating pseudo-rotation modulation effectively eliminates the zero bias caused by the circumferential inhomogeneity of μHRGs. Experimental results validate the reliability and effectiveness of the proposed adaptive PI algorithm.