A MEMS Doubly Decoupled Gyroscope With Wide Driving Frequency Range

This study developed a microelectromechanical systems (MEMS) doubly decoupled gyroscope with a wide driving frequency range. The gyroscope increases the resonance bandwidths of both the drive and sense oscillators without sacrificing their Q factors. This bandwidth enhancement ensures good frequency matching between the drive and sense oscillators even if fabrication imperfections are present. Additionally, no in-operation frequency tuning mechanism is needed. The gyroscope can be driven at any frequency within the overlapping region of the resonance bands of the drive and sense oscillators. Experiments showed that the gyroscope driving voltage can be of any frequency within a ~240-Hz bandwidth. The wide bandwidth provides flexibility and ease of use. The device is fabricated by the MetalMUMPs process developed by MEMSCAP, Inc. Its doubly decoupled structure minimizes the interference/coupling between the drive and sense units. Performance tests under rotation rates equal to or smaller than 18.71 rad/s showed that the gyroscope has a sensitivity of 4.28 mV/(rad/s).