Frequency Tuning Control for the Drive Mode of a Bulk Z-axis Micro-machined Gyroscope

The work presented focuses on frequency tuning control for the drive mode of a Z-axis double decoupled micro machined gyroscope. Different from traditional self-oscillation closed-loop, the approach adopted in this study doesn't drive the gyroscope with resonant frequency, but with fixed vibration phase. The detected phase is compared with the one specified by the designer or the frequency sweep for a feedback to adjust the drive signal's frequency according to the phase's frequency response. Simulation based on mat lab and experiments with FPGA as the signal processing unit were made in order to measure the vibration stability. The vibration variation is 9.7ppm while the start time is 0.2s. The results indicate that the controller enjoys the advantage of fast startup time and stable vibration parameters, is easy for system modeling and controller design and suitable for digital implementation.