Microfabricated tuning fork gyroscope and associated three-axis inertial measurement system to sense out-of-plane rotation

摘要

A micromechanical tuning fork gyroscope has an input axis out of the plane of the structure. Proof mass combs of a comb drive are meshed between fixed drive combs which are electrically excited in pairs 180° out of phase. As the proof masses translate in response to an angular input, the distance between the proof mass combs and the fixed combs varies, thereby varying the capacitance between the combs resulting in an unbalanced voltage on the proof masses that is detected as an indication of input rate. The out-of-plane tuning fork gyroscope can be combined with two in-plane tuning fork gyroscopes to provide a complete three-axis inertial measurement unit from a single wafer or on a single chip.