Online Compensation of Phase Delay Error Based on P-F Characteristic for MEMS Vibratory Gyroscopes

Abstract

In this paper, an online compensation method of phase delay error based on a Phase-Frequency (P-F) characteristic has been proposed for MEMS Coriolis Vibratory Gyroscopes (CVGs). At first, the influences of phase delay were investigated in the drive and sense mode. The frequency response was acquired in the digital control system by collecting the demodulation value of drive displacement, which verified the existence and influence of the phase delay. In addition, based on the P-F characteristic, that is, when the phase shift of the nonresonant drive force through the resonator is almost 0° or 180°, the phase delay of the gyroscope is measured online by injecting a nonresonant reference signal into the drive-mode dynamics. After that, the phase delay is self-corrected by adjusting the demodulation phase angle without affecting the normal operation of the gyroscopes. The approach was validated with an MEMS dual-mass vibratory gyroscope under double-loop force-to-rebalance (in-phase FTR and quadrature FTR) closed-loop detection mode and implemented with FPGA. The measurement results showed that this scheme can detect and compensate phase delay to effectively eliminate the effect of the quadrature error. This technique reduces the zero rate output (ZRO) from −0.71°/s to −0.21°/s and bias stability (BS) from 23.30°/h to 4.49°/h, respectively. The temperature sensitivity of bias output from −20 °C to 40 °C has reached 0.003 °/s/°C.

Development of an Optoelectronic Integrated Sensor for a MEMS Mirror-Based Active Structured Light System

“…However, capacitive sensing methods suffered from poor repeatability, low signal-to-noise ratios, and material limitations when using small MEMS devices in space-constrained applications. Various feedback control algorithms have also been proposed to reduce phase errors [ 18 , 19 , 20 , 21 ].…”

Interactive Errors Analysis and Scale Factor Nonlinearity Reduction Methods for Lissajous Frequency Modulated MEMS Gyroscope

“…The phase lags exist in each block of the MEMS system, contributing to driving force deflection and resulting in PLL tracking errors. While the impact of phase errors has been studied in AM and WA operations, its effect on the LFM operation remains unknown [ 32 , 33 ]. Coincidentally, when there is a deviation angle between the force and the mode, it generates a component force in the orthogonal direction, which resembles the impact of the system phase error on the driving force deflection [ 34 ].…”