The Self-calibration And Error Suppression Technology Of Hemispherical Resonator Gyroscope

Hemispherical resonant gyroscope is a new sensor which uses Coriolis effect to measure angular rate.It has the advantages of high precision,high reliability,low power consumption,miniaturization and reliable life.It is considered to be one of the most potential development directions of the next generation gyroscope.With the attack and defense game between countries,the weapon system,based on intelligence and miniaturization,requires the system with hemispherical resonant gyroscope as the core to develop in the direction of high stability and high-precision measurement.The measurement accuracy of hemispherical resonator gyroscope will be in the bottleneck period,due to the imperfect manufacturing process of resonator,weak encapsulation and the influence of a variety of error.In order to further improve its stability and measurement accuracy,it will face great technical problems and challenges.In order to achieve high stability and high accuracy measurement of hemispherical resonant gyroscope,this thesis researches the self-calibration technology and error suppression technology of hemispherical resonant gyroscope,firstly,through the analysis method of equivalent system,the vibration model of hemispherical resonant gyroscope is equated to the simple harmonic motion of a two-dimensional spring resonant oscillator,and the dynamics equation of resonant oscillator under ideal condition is given,based on which the stiffness inhomogeneity and damping inhomogeneity are introduced.Then,based on the second-order error model of the hemispherical resonant gyroscope in the non-ideal case,the corresponding error suppression scheme is proposed for the bias of the gyroscope,the accumulation of residuals such as the scale factor error and periodic bias,and the drift caused by the damping inhomogeneity,etc.The detailed theoretical derivation and the block diagram of the principle implementation are given,and the feed-forward compensation method is adopted to The drift caused by damping inhomogeneity is compensated;the periodic integration method is adopted to reduce the accumulation of constant scale factor error and periodic bias residuals;the dual gyroscope self-calibration method is adopted to realize the bias self-calibration of hemispherical resonant gyroscope and improve the bias stability of the gyroscope;finally,based on the algorithm timing of self-calibration,the analysis and division of the simulation working timing is carried out,and the timing phase of the dual gyroscope self-calibration system is divided into four working phases and four transition phases.Finally,based on the selfcalibration algorithm timing,we analyze and divide the simulation working timing,divide the timing phase of the dual gyroscope self-calibration system into 4 working phases and 4transition phases,establish the state space system equations of each phase,and simulate the angular rate signals of gyroscope A and gyroscope B based on the state space equations,realize the data fusion of the two angular rate signals,and finally get the smooth and stable gyroscope angular rate output signal.Taking the hemispherical resonant gyroscope researched by this group as the object,firstly,the overall implementation of the hemispherical resonant gyro signal processing and control system based on the SOC circuit,the error suppression experimental test is carried out by the feedforward compensation of damping inhomogeneity error scheme proposed in this thesis,which reduces the angular drift of the gyroscope from 0.895°/s to 0.048°/s before compensation,and reduces the angular drift caused by damping inhomogeneity.Then the error suppression experimental test is carried out by the periodic integration error compensation scheme proposed in this thesis,which reduces the angular drift of the gyroscope from 0.895°/s to 0.0012°/s before compensation,reduces the accumulation of residuals such as constant zero bias error and periodic zero bias,and verifies the effectiveness of the periodic integration technique.Finally,the experimental test was carried out by the scheme of double gyroscope self-calibration zero bias drift system proposed in this thesis,which reduced the zero offset drift of gyroscope from0.003°/s to 0.00078°/s.The double gyroscope self-calibration technique has significantly improved the gyroscope performance and verified the effectiveness of the double gyroscope self-calibration technique.