Analysis And Design Of Hemispherical Resonator Gyro

The hemispherical resonator gyro (abbreviated as HRG) as an vibrating inertial instrument works on the coriolis effect that has a promising prospect for its several advantages such as high precision, high reliability and longevity and so on. The working principle of HRG is based on the physics mechanism that the vibrating shape of resonator precesses about the resonator shell by the coriolis effect when the resonator is rotated about its axis.The key technique of HRG about the mathematical model,dynamical characteristics,drift characteristics,structure parameters,signal system and errors have been analyzed,studied and designed-in detail in this paper, the main works are as follows:Firstly, two kinds of resonator's typical mathematical models are studied, based on the studied results, the vibrating characteristic is analyzed. Resonator's two dimension vibrating model is established by use of the method of lumped parameter, gyro drift can be studied by it. During the analysis of two dimension vibrating model for gyro drift, the method of resonator's trajectory is introduced, the vibrating characteristics of resonator can be obviously reflected by trajectory, at the same time, the influence of spring coefficient and damping coefficient for gyro drift is analyzed.According to the theory and method of finite element analysis, the vibrating mode of resonator is studied, the structure parameters of resonator is analyzed and designed. Analyzing the resonator's vibrating mode ofΨtype,Y type and umbrella type whose structure parameters have been chosen, aiming at the resonator ofΨtype, the relationship of structure parameters and resonant frequency is analyzed. In the analysis of vibrating mode, the resonant frequency of vibrating shape's ring wave with two is chosen as design specification, the precision which should be obtained in the process of resonator machining is calculated. In addition, by the study of resonator with slots on the top, the relationship of slot parameters and resonant frequency is analyzed.The signal system of HRG is studied in detail in this paper, the principle of signal detection and control is analyzed, the signal system of HRG is designed. Aiming at the signal characteristic of HRG, a kind of signal processing method is designed, the signal of HRG can be detected by the method. In the study of quadrature control, the proportion of excited force by adjacent discrete electrodes is deduced. According to the requirement of quadrature control, the discrete electrodes is grouped, and the position formula of discrete electrodes around the resonator circumference is calculated. The method of discrete electrodes combination and control is put forward by comparison the relationship of ideal vibrating mode and factual vibrating mode, and the quadrature control project by use of discrete electrode is designed.At last, this paper analyzes the errors of HRG, the influence of resonator structure parameters deviation for performance of HRG is discussed, the errors of precession coefficient and precession angle caused by resonator parameters deviation and electrodes parameters deviation is calculated, and parts of errors specification for HRG are given. In addition, this paper analyzes the influence for gyro drift because of the asymmetry of radius,damp and density around the resonator circumference.Research results for HRG in this paper will be a very useful reference for engineering design and manufacture of HRG.