A novel design of MEMS gyroscope with control capability

Abstract

High performance MEMS gyroscopes can be implemented by embedding in a closed loop controller. For these gyroscopes, the electrostatic controlled force on the proof mass is inherently nonlinear. This study reports a MEMS gyroscope with control capability in which comb drive electrodes are employed as the controlling mechanism to linearize the electrostatic controlled force. To avoid interaction of drive and control comb drive electrodes, another mass has been added to the structure. Consequently, proposed gyroscope consists of a 2-DOF sense mode oscillator and a 1-DOF drive mode oscillator. The prototype with an overall size of 0.46 × 0.635 mm is designed to be fabricated in surface Micromachining process with 3 μm structural layer thickness. The device operation has verified by Finite Element Method simulations showing a raw mechanical sensitivity of 32 nm for drive direction oscillation amplitude of 120 nm and angular rotation of 50 [°/s].