Scale Factor Nonlinearity of Hemispherical Resonator Gyro

Abstract

The measuring device - the hemispherical resonator gyro working in the mode of free fluctuations is considered in the paper. Increase in accuracy of the hemispherical resonator gyro always remains a relevant task. The hemispherical resonator gyro is the measuring system comprising the measuring component. The imperfection of the measuring component affects precision characteristics of the device in general. Errors in the measuring component lead to emergence of nonlinearity of the large-scale coefficient. In the paper this type of an error is investigated; the approach is offered to the increase in accuracy of an output signal due to the use of information on nonlinearity of the large-scale coefficient. The possible reasons of nonlinearity of large-scale coefficient like different coefficients of strengthening of sensors of movement of the system of renting, deviations from the necessary angular placement of sensors, and nonlinearity of transformation of sensors are investigated. The major factor of an error - angular orientation of a wave comes to light. Influence of nonlinearity of the large-scale coefficient on a control system is analyzed. Several ways of measurement of nonlinearity and assessment of its accuracy are given. Recommendations on what ways of measurement are more convenient and more effective in certain cases are made. The influence of the wave drift and noise component of signals on the accuracy of assessment of nonlinearity of the large-scale coefficient is described. The technique of increasing the accuracy of an output signal due to fine tuning in the computing component of the hemispherical resonator gyro of phase variables of a wave picture is offered. The residual influence of nonlinearity is offered to be reduced due to compensation of the error. Questions of implementation of nonlinearity compensation are analyzed. Another possible factor of nonlinearity - the temperature - is considered. The way of measurement of this factor is described. Unification of models of nonlinearity and drift is proposed in order to increase the efficiency of compensation of errors of an output signal of the hemispherical resonator gyro.