Performance characterization of a decoupled tri-axis micro angular rate sensor

摘要

A novel tri-axis micro-gyroscope is proposed in this paper. Three orthogonal axis angular rates, pitch, yaw, and row, can be detected simultaneously by the designed micro-gyroscope. The coupling effect of the tri-axis angular rates due to Coriolis response and nonlinearity of the high frequency modes can be efficiently reduced by the decoupled mechanical structure design. Firstly, an 8 × 8 linearized state-space representation with a holonomic constraint is established and the relative stability is investigated. Secondly, the mathematical description and discussion upon performance indices for micro-gyroscope such as sensitivity, nonlinearity, and resolution are addressed. In addition, the quality factor is verified to be a significant design parameter for the micro-gyroscope. The performance and stability of the gyroscope could be degraded by choosing inappropriate quality factors. Moreover, the trade-off among performance indices for the gyroscope is theoretically evaluated and discussed. Finally, in order to meet most performance specifications, a pole/zero mapping design method is proposed to satisfy either large bandwidth or high resolution requirements.