Establishment of steady state model of amplitude-control for hemispherical resonator gyro under force-rebalance mode

Amplitude-control of the main excitation and the rebalance excitation is an important part of force-rebalance control system of HRG under force-rebalance mode. Controlling the voltage values of the two excitations could be used to make the azimuth of radial vibration antinode be the same as that of the main excitation. In order to accurately control the voltage values, the state equation about vibration displacement and velocity was established based on the dynamics equations of resonator with the density distributed nonuniformity in the circular direction, and the representations of the two excitation's voltage values were achieved by solving the state equation. The relationships among the input angle rate, the defection of resonator and the force-rebalance voltage were got by the force-rebalance voltage representation, which lay a foundation for the vibration amplitude-control and the error analysis. By calculating the excitation voltage and contrasting with the voltage of practical HRG, the correctness of the established steady state model of amplitude-control for HRG are proved.