Research on System Level Calibration Method of Strap-down Inertial Navigation System

In order to effectively improve the accuracy of strap-down inertial navigation, it is necessary to recognize and compensate the error of high-precision inertial navigation system. In this paper,not only the conventional error parameters such as zero bias error, scale factor error, and installation error of the inertial measurement assembly are considered from the system perspective, but also quadratic term coefficient error of accelerometers, the rod arm error, and the time asynchronous error are analyzed. By designing the calibration paths to rotate and stop around the three sensitive axes of the inertial component to stimulate the error parameters of the inertial measurement component, a high-dimensional Kalman filter is established to recognize the error parameters. At the same time, this paper carries out Sage-Husa adaptive processing for the traditional Kalman filter noise parameters. The simulation results show that the designed system-level calibration method can estimate all the error parameters, which is of great significance for improving the accuracy of inertial navigation.