Implementation and Experiment of Dual-mass Vibratory Gyroscope with High Quality Factor

The implementation of the dual-mass MEMS vibratory gyroscope in device-level vacuum packing was presented. The electrostatic actuation and capacitive sensing methods were adopted in electrical design of gyroscope. The self-resonance drive circuit with automatic gain control was employed in the drive closed-loop, and the open loop detect circuit was used. In order to reduce environment impact on the performances of gyroscope, real-time temperature compensation system was designed using Platinum resistor as temperature sensor. Experiment results show that the MEMS gyroscope can achieve the performances as follows: mechanical quality factor is above 100 000, the operating range is +/- 500 degrees / s with scaling factor 21.453mV/degrees/s, nonlinearity and asymmetry error are better than 200ppm, and the 1 sigma bias stability <8 degrees / h with the bandwidth over 100Hz. The complete MEMS gyroscope draws about 11mA under power supply +/- 12V, and the whole system volume is 31mm(star)31mm(star)12mm.