Calibration of Channel Error in Dual-Channel Synchronous Control Circuit for Rate Integrating Hemispherical Resonator Gyro

Accurate detection and excitation of standing wave on resonator are crucial for achieving Rate-Integrating Hemispherical Resonator Gyro (RI-HRG). The imbalance electrical characteristics between channels in detection signal chain and excitation signal chain of the dual-channel synchronous control circuit are the main factor causing detection error and excitation error of standing wave. In this paper, a comprehensive error model, including unbalance gain error and misalignment angle error, is established at first. Then the negative impacts caused by the detection error and excitation error on angular rate demodulation, multi-loop control and excitation force misalignment are analyzed respectively. On this basis, a specific identification and compensation method for unbalance gain error and misalignment angle error is proposed with minimal error coupling interference. Finally, the proposed method is validated with experiments. The experimental results show the effectiveness of the method and the non-ideal precession of hemispherical resonator standing wave is effectively suppressed.