Abstract
The current dual-axis vibratory wheel gyroscopes are mostly designed to have merely one proof mass, so the sensing signal measured from the two axes will interfere with each other and will result in zero rate output. This study presents a novel design of dual-axis sensing decoupled vibratory wheel gyroscope. The main structure, which consisted of three proof masses, can measure the angular rate of two different axes independently. A triple-beam-shape torsional spring is used to suppress the undesired in-plane linear motion of the proof mass. A prototype gyroscope design was employed to verify the concept and the performance of the present design concept. The simulation results show that the natural frequencies of the driving mode and the dual-axis sensing modes are 4585, 4604, and 4606 Hz, respectively. It successfully demonstrates that the dual-axis sensing modes are decoupled with each other. With the driving voltage of 20 V and the quality factor of 2000, the sensitivities of the dual-axis sensing modes can reach 7.4 and 19.4 fF/°/s, respectively, and the nonlinearity of the dual-axis sensing modes are only 0.04 and 0.29% within the dynamic range of ±150°/s. © 2005 Elsevier B.V. All rights reserved.