Innovation of flat gyro: Center Support Quadruple Mass Gyroscope

This paper reports a novel Center Support Quadruple Mass Gyroscope (CSQMG), which combines the advantages of tuning fork gyros (TFGs, large mass and high resolution) and the micro hemisphere resonant gyros (MHRGs, fully symmetric and high Q), and is expected to achieve performance breakthrough of flat structures. The operation of the CSQMG is based on four proof masses symmetric distributed circumferentially, oscillating in anti-phase motion, and differential signal extraction, resulting in a Q-factor over 8000 at a center frequency of 6.8 kHz in the pressure of 30 Pa. The experimental characterization of the CSQMG is proceeded at room temperature, showing Allan variance stability 0.12°/h (@100s) and the white noise level about 0.72 °/h/√Hz, which means that the CSQMG possesses great potentials to achieve navigation grade performance. Furthermore, a new kind of PI control method for rebalancing decoupling force has been developed to expand the bandwidth of CSQMG to more than 50Hz.