Design, Analysis, and Experimental Results of Micromachined Single-structure Triaxis Vibratory Gyroscope with Advanced Coupling Mechanism

Abstract

In this work, a novel micromachined monolithic triaxis gyroscope with an advanced anchor mechanism is designed and its structural characteristics are analyzed. Micromachined gyroscopes are usually packed in small packages, causing a high squeeze film damping effect that reduces the quality factor of out-of-plane vibration, resulting in lowered out-of-plane sensitivity. The proposed gyroscope has a four-mass single structure wherein the opposing masses vibrate in the opposite direction perpendicular to the direction they face, with the help of 'tree-shaped' coupling springs. The simulated driving and x-, y-, and z-axis sensing resonant frequencies are 19946, 20227, 20294, and 20361 Hz, respectively. Also, the prototype of the gyroscope was fabricated and tested. It showed a driving Q-factor of 106 and a scale factor of 7 mV/deg/s.