Method for calibrating fixed errors of inertial sensor in inertial navigation system in real time

Abstract

The invention discloses a method for calibrating fixed errors of an inertial sensor in an inertial navigation system in real time. The method comprises the following steps of: firstly, establishing a fixed error model of the inertial sensor during the dynamic flying process of an aircraft, wherein the fixed errors include installation errors and scale factor errors; secondly, establishing a state equation and a position, speed and attitude linear measurement equation of a filter, with the fixed errors of the inertial sensor included, on the basis of a random error model of a traditional IMU (Inertial Measurement Unit) and the established fixed error model; and finally, carrying out real-time dynamic calibration and correction to the fixed errors of the inertial sensor during the dynamic flying process of the aircraft, so as to obtain the navigation result of the inertial navigation system after the fixed errors of the inertial sensor are compensated and corrected. The method can realize the calibration and correction of installation errors and scale factor errors of the inertial sensor used in the inertial navigation system during the dynamic flying process of the aircraft, effectively enhances the performance of the inertial navigation system, and is suitable for engineering application.

Description

technical field [0001] The invention discloses a real-time calibration method for fixed errors of inertial sensors in an inertial navigation system, belonging to the technical field of calibration of inertial sensor errors for inertial navigation. Background technique [0002] In recent years, with the development of new aircraft, the requirements for the performance of the navigation system are increasing. The inertial navigation system has the outstanding advantages of high short-term accuracy, continuous output and complete autonomy, and it must be the core navigation information unit of future new aircraft. [0003] The measurement error of the inertial sensors (IMU - gyroscope and accelerometer) is the main factor affecting the accuracy of the inertial navigation system. In the traditional IMU error model, it is often considered that its fixed errors—installation errors and scale factor errors are fully compensated after static calibration, and the IMU errors only incl...

AI Technical Summary

Problems solved by technology

However, during the dynamic flight of the aircraft, due to the influence of the environment, the traditional calibration method using the turntable will no longer be applicable

During the dynamic flight of the aircraft, the traditional error correction of the inertial sensor is only for its random error, and does not consider the influence of fixed errors such as its installation error and scale factor error.

However, the installation error and scale factor error caused by flight vibration and other influences will greatly affect the accuracy of the inertial navigation system, and it must be calibrated and compensated.

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