Scale Factor Performance Research Articles

Direct Phase Measurement and Compensation to Enhance MEMS Gyroscopes ZRO Stability

This research introduces a closed-loop method to improve the zero-rate output (ZRO) stability of amplitude-modulated (AM) capacitive MEMS gyroscopes, even in absence of quadrature compensation electrodes. The method relies on the direct measurement and closed-loop compensation of the variation of the relative phase between the quadrature output, modulated by the drive carrier frequency, and the demodulation reference. The closed loop includes a phase meter, whose output regulates the phase of the lock-in amplifier inside the sense-mode, open-loop, demodulation chain. The proposed technique, tested on the pitch axis of a consumer-grade commercial monolithic 3-axis gyroscope, brings up to 300-fold stability improvements over temperature transients, without affecting noise and scale-factor performance. Stability limits depend on the phase meter resolution and on the lock-in granularity in regulating the phase. Overall, a mdps/K stability is obtained with a one-time calibration at ambient temperature and no post-acquisition processing. [2021-0049]

고속회전 감지 광섬유자이로 설계

본 논문은 광섬유 간섭계의 제한된 회전 측정범위(<TEX>$\pi$</TEX>/2[radian]) 확장을 통하여 고속 회전입력을 감지할 수 있는 광섬유자이로 설계에 관한 연구 결과를 기술하였다. 디지털 세로다인 변조 기법을 바탕으로 광섬유자이로 신호처리 회로를 설계하였으며, 제작된 프로토타입 광섬유자이로의 시험결과 약 <TEX>${\pm}3000[deg/sec]$</TEX>의 고속 회전측정 성능과 약 150[ppm]의 환산계수 성능을 확인하였다. 따라서 본 논문에서는 고속회전 감지를 위한 광섬유자이로 설계의 유효성이 검증되었다. We studied the design of fiber optic gyroscope that enables to sense high rotation by extending the limit of rotation sensibility of fiber optic interferometer. Based on the digital serrodyne modulation technique, the signal processing of fiber optic gyroscope was designed and the prototype fiber optic gyroscope showed the high rotation sensibility up to <TEX>${\pm}3000[deg/sec]$</TEX> and scale factor performance of about 150[ppm] by the experiments. Accordingly, we confirmed that the design of fiber optic gyroscope was valid for high rotation.