Research On Error Mechanism And Simulation Of Hemispherical Resonator Gyro

Hemispherical resonator gyro(HRG)is a new type of solid vibration gyroscope with the advantages of high precision,high stability,long life,which is very suitable for using in spacecraft,deep space exploration and other long-term work occasions.The development of HRG technology is of great significance to the rapid development of Chinese navigation technology.At present,the structural errors of gyroscope and environmental factors are the important factors that affect the accuracy of gyroscope.Based on resonator dynamic model,it is analyzed that acceleration and eccentricity error lead to the gyro drift mechanism.The corresponding error compensation method is proposed to ultimately achieve the purpose of improving gyro’s precision.The main contents of this paper are summarized as follows:Firstly,dynamic model of resonator in the the second-order resonant state is established.Based on the elastic shell theory,dynamics modeling method of resonator is proposed.The deformed geometric equation,physical equation and balanced differential equation of hemispherical resonator are deduced.The dynamic equations of resonator are established for the dynamic analysis of the whole resonator.The external load form of resonator is deduced in detail.The dynamic model is solved by Bubnov-Galerkin method.The expression of proportional coefficient and second-order resonant frequency of resonator are given.The calculated values are compared with the measured data.Secondly,based on the dynamic equation under the action of acceleration,considering the influence of acceleration on resonator,the analytical expression of the resonator under the acceleration effect is given.The method of verifying the analytical solution of the dynamic modeling and the numerical solution of the finite element simulation is presented.The fitting error results of the analytical solution and the finite element simulation solution are given.Thirdly,the mechanism of gyro drift caused by acceleration is analyzed.The dynamic model of resonator under multi-electrode excitation is established.Combined with this model,the control method of adding and rationally arranging the excitation electrodes is proposed.The influence of acceleration on HRG control system under different control modes is analyzed.Based on the analysis of gyro drift mechanism,the gyro drift error model is eatablished.The gyroscope location roll test completed on the three-axis turntable,the gyro drift was tested.Gyro drift is compensated by using gyro drift error model and the compensation result is given.Finally,the mechanism of gyro drift caused by eccentricity error is analyzed.The eccentric error model is deduced.The influence of eccentricity error on HRG control system under different excitation electrode control method is analyzed by combining the dynamic characteristics of multi-electrode excited resonator.The simulation results of gyro drift caused by eccentricity error are analyzed by establishing simulation algorithm.The improvement measures in the process of gyro’s manufacturing and assembling are put forward.