A novel AT-cut gyroscope, its analysis and design

A novel AT-cut quartz vibratory gyroscope with a sensitivity to angular velocity of 1.3 mV/deg./s was presented. The gyroscope employed the thickness shear mode as the driving mode and the flexure mode of tines as the sensing mode. The tines are placed normally on the AT-cut quartz plate surface. These tines were tuned to resonate with the harmonic Coriolis body force caused by the angular rotation of the plate about its plate thickness axis. The flexure mode of the tines changed with the angular velocity about the thickness axis of the plate. The change in the flexure mode of the tines could be detected by the sensing electrode separated from the driving electrode by an acoustic gap. Since the AT-cut resonators are known to have good f-T curves and long term aging, the new AT-cut gyroscope would have the advantages of a highly stable quartz AT-cut resonator.