Calibration of Inertial Sensors in the Case of Varying Temperature

The calibration of a strapdown inertial navigation system is considered in the case of varying temperature. A parameterized model of measurement errors is used to calibrate the inertial sensors. In addition to usual standard parameters, this model contains the coefficients in the temperature dependence. In the author’s previous publications, it is shown that it is possible to estimate these coefficients and the coefficients in the dependence describing the time derivative of temperature as well as the other parameters. The practical application of this author’s approach is based on the following: the time dependence of temperature is determined using the temperature sensors mounted on the navigation system under study. The determination of this derivative on the basis of the temperature sensors is not a trivial problem. In this paper we propose a function to approximate the readings of temperature sensors. The relation between this function and the model of thermal processes inside the navigation system is analyzed. This process is described by the heat conduction equation.