Modeling and First Characterization of Broad-Spectrum Vibration Rejection of Frequency Modulated Gyroscopes

Abstract

The work presents a detailed modeling and the first-ever characterization of a frequency modulated (FM) yaw gyroscope in presence of vibrations from low frequency (30 Hz), through the main modes, and up to 40 kHz. The gyroscope two in-plane axes (around 25 kHz) are operated under a Lissajous trajectory (70 Hz period) by an integrated circuit (IC) including oscillators, frequency digitization, and digital demodulation stages. In presence of $2-g_{pk-pk}$ vibrations, no effects are visible across the spectrum apart from the region including the modes. In this range, as predicted by theory, for each axis no effect is observed for accelerations at the axis resonance (< 0.1 dps/g), but a huge effect (tens of dps/g) is visible for accelerations at an offset frequency from resonance corresponding to the mode split.