Cantilever beam microgyroscope based on Frequency modulation

This paper reports on-going research progress towards the development of an innovative frequency modulation MEMS gyroscope. The microgyroscope design includes a cantilever beam with a proof mass at its free end coupled electrostatically with two fixed electrodes. The beam is designed with silicon nitride and a layer of electrode material (Au). The microgyroscope undergoes coupled flexural vibrations in two orthogonal directions when subjected to base rotation around the beam´s longitudinal axis. The rotation rate is measured by detecting the shift in the frequencies of the two closely spaced global vibration modes. A modeling framework is presented here for the development of the microgyroscope´s frequency equation. The governing equations are derived using the Extended Hamilton´s Principle and solved numerically to incorporate the nonlinear behavior. Currently, the device is in the process of fabrication using Silicon on Insulator (SOI) wafer using a micromachining process, including Deep Reactive Ion Etching.