Enhanced sensitivity in a butterfly gyroscope with a hexagonal oblique beam

A new approach to improve the performance of a butterfly gyroscope is developed. The methodology provides a simple way to improve the gyroscope’s sensitivity and stability, by reducing the resonant frequency mismatch between the drive and sense modes. This method was verified by simulations and theoretical analysis. The size of the hexagonal section oblique beam is the major factor that influences the resonant frequency mismatch. A prototype, which has the appropriately sized oblique beam, was fabricated using precise, time-controlled multilayer pre-buried masks. The performance of this prototype was compared with a non-tuned gyroscope. The scale factor of the prototype reaches 30.13 mV/ ˚/s, which is 15 times larger than that obtained from the non-tuned gyroscope. The bias stability of the prototype is 0.8 ˚/h, which is better than the 5.2 ˚/h of the non-tuned devices.

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