Design of a Micromachined Vibratory Gyroscope with Multi-Sense-Mode Oscillators

摘要

This paper presents a novel gyroscope design of micromachined vibratory gyroscope with better gain characteristics while retaining the wide bandwidth. This design is based on using four 2-degree-of-freedom (DOF) sense-mode oscillators with incrementally spaced central frequencies which, unlike previous multi-DOF gyroscopes, achieves a wide bandwidth and a gain advantage in the sense-mode. To improve the robustness of the gyroscope, the bandwidth of the complete 2-DOF drive-mode is designed to be matched with that of sense-mode. Simulation results demonstrate that a 3 dB bandwidth of 210 Hz and 350 Hz are provided in the 2-DOF drive-mode and sense-mode, respectively. The resonant frequencies of the drive-mode are highly matched with those of sense-mode between 4.89 kHz and 5.10 kHz. In this region, the gain attenuation of sense-mode is 1.1 dB and not sensitive to structural parameter fluctuations at the central operational frequency of 5.0 kHz. Compared to the frequency response of a single distributed sense-mode oscillator, the frequency response of sense-mode is increased by 12 dB approximately in the region of 4.89-5.10 kHz.