Utilization of Internal Resonance in Gyroscope Design

Coriolis vibratory gyroscopes (CVG) suffer from various error sources including manufacturing imperfections and environmental factors. Most design constraints incorporate having the drive and sense mode natural frequencies equal. This poses a difficult solution called “mode matching” requiring complex and extremely accurate on-chip electronics. The research discussed in this thesis acts as a proof of concept on utilizing well-established phenomena in the field of nonlinear dynamics and vibration in the design of CVG gyroscopes with improved stability against manufacturing imperfections. A significant increase in the sense mode bandwidth is shown by structurally tuning the system to 2:1 resonance between the sense and drive modes respectively. A simplified mathematical model of a two-degree-of-freedom system, having quadratic nonlinearities, is obtained and compared qualitatively to more complex models from literature. Experimental results verify numerical simulations, confirming the hypothesis. Additional bandwidth enhancement possibility is established through simple feedback of nonlinear coupling terms obtained from mathematical models.