IMU full parameter error fast calibration method based on backtracking theory

Abstract

The invention discloses an IMU full parameter error fast calibration method based on the backtracking theory. A calibration trajectory of forward and reverse rotation under three positions is designed. The observability of the error state is analyzed through the error propagation law of the inertial component, and the IMU full parameter error can be rapidly calibrated in a short period of time bythe calibration method based on the backtracking frame theory. The method has the beneficial effects that the calibration method based on the system level can calibrate the zero position error, the scale factor error and the installation error of the fiber optic gyro and the accelerometer and the rod arm error of the accelerometer in the dynamic environment. The arrangement of the calibration trajectory can be simplified, the calibration time can be greatly shortened and the efficiency of IMU error calibration can be improved.

Description

technical field [0001] The invention relates to the technical field of calibration, in particular to a fast calibration method for IMU full parameter errors based on backtracking theory. Background technique [0002] Strapdown inertial navigation systems provide navigation information without external interference. However, the errors of SINS will accumulate and diverge over time, which will seriously restrict its navigation performance. Inertial sensor error is the main source of SINS error divergence. Accurate calibration of error parameters is the key to ensure the performance of inertial navigation. At the same time, the calibration of the IMU is also one of the key links before the operation of the strapdown inertial navigation system, which requires high accuracy and speed. [0003] At present, traditional IMU calibration methods include discrete calibration and system-level calibration. Discrete calibration generally relies on a high-precision turntable to provide...

AI Technical Summary

Problems solved by technology

[0004] Although the traditional system-level calibration method has the advantage of not relying on the accuracy of external equipment, due to the high dimension of the system state, the amount of calculation is large, and the required calibration time is long, usually half an hour or even more than an hour. Calibrate all IMU error parameters

At the same time, in order to excite all the error parameters, the design of the calibration path is quite complicated, too long calibration time will greatly reduce the efficiency of navigation

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