Effective rejection of acoustic and magnetic fields’ disturbances by single-mass differential vibratory gyroscope

Abstract

Differential mode of operation as a third mode unlike the first one - rate and second one - rate-integrating modes of vibratory gyroscopes is analyzed in this paper. In the differential mode of operation the standing wave is keeping in between the electrodes. In this case two X and Y measurement channels are created with opposite signs of angle rates. Biases and scale factors of X and Y measurement channels are dependant on standing wave angular position θ relative to drive, X, electrode. There is angular position θ * at which X measurement channel scale factor SFx is equal to Y measurement channel scale factor SFy. Rejection factors of external acoustic impulses which frequency is close to resonant one, and also of constant and variable magnetic fields are experimentally determined in this paper when standing wave angle is located at the θ * angular position. As opposed to other types of differential gyros that can be implemented using two or multi-mass resonator designs, single-mass resonator gyros can have higher rejection factors for different disturbances at the θ * angular position of standing wave providing meeting the requirements of many important applications. Test results show excellent disturbance rejection properties of differential mode of operation for single-mass resonator gyros. Comparison of responses of the differential mode with the rate mode of the same gyro on disturbances is also carried out in this work.