Papers by Author: Hong Chen

Abstract: This paper researches on the temperature effects of a fully-symmetrical micromachined gyroscope. The Young’s modulus and thermal expansion coefficient of silicon vary with the environment temperature, which affects the modes’ resonant frequencies of micromachined gyroscopes. The effects of temperature fluctuation on the modes’ resonant frequencies is simulated by the FEM software ANSYS. The simulation results show that the fully-symmetrical gyroscope’s resonance frequencies decrease with the increase of temperature and the decrease degree nearly 0.256Hz/°C, but the two modes’ resonance frequencies matches well. The micromachined gyroscope’s dynamic characteristics are tested. The resonant frequencies and the quality factor are reduced with the increase of temperature and the decrease degree of the fit linear about the resonant frequencies is 0.276 Hz/°C. The test results are in good accordance with the simulation results.

Abstract: This paper presents a novel bulk micromachined gyroscope with the compensatory capacitance. Independent driving and sensing beams and a dual-frame structure are adopted to decouple mechanically for stable operation. The method of electrostatic push-pull drive and capacitive sense combs based on the slide film damping are applied to obtain a large driving force and high quality factors. The compensatory capacitance is designed to compensate the deviations of sensing differential capacitance from fabrications. The designed gyroscope has matched resonant frequencies of 2187Hz and 2206Hz for the drive and sense modes, respectively. Considering the noise of interface circuits, the gyroscope system sensitivity can reach 14.2mv/o/s, theoretically.