Marine fiber optic gyroscope attitude heading reference system mooring accurate alignment method under the large misalignment angle

Abstract

The invention provides a mooring fine alignment method for a marine optical fiber gyro strapdown attitude system under a large misalignment angle. For the ship's fiber optic gyro strapdown attitude system in the mooring state, based on the coarse alignment of the collected gyroscope output and accelerometer output information (due to large surge, sway, and heave attitude errors), Establish the conversion matrix between the carrier coordinate system and the calculation geographic coordinate system to determine the quaternion error; establish the Kalman filter state equation with the quaternion error and the velocity error as the state variable and the measurement equation for the measurement of the velocity error; Using the obtained quaternion error and the quaternion corresponding to the attitude matrix at the initial moment, calculate the quaternion corresponding to the transformation matrix between the carrier coordinate system and the inertial system, and initially align. In the case of a large misalignment angle, the system equation is still linear, and the relatively mature Kalman filter can be used for filter estimation with high precision and good reliability; High accuracy.

Description

(1) Technical field [0001] The invention relates to a measurement method, in particular to an alignment technology of a strapdown heading attitude system, and in particular to a mooring fine alignment method of a marine optical fiber gyro strapdown heading attitude system. (2) Background technology [0002] The strapdown attitude system is a navigation system that connects the inertial instrument to the carrier and uses a computer to complete the navigation platform function. Compared with the platform inertial navigation system, it has the advantages of small size, light weight, low cost, high reliability, and easy maintenance. advantages, so it has been more and more widely used. And its navigation accuracy largely depends on the accuracy of the initial alignment. The initial alignment is generally divided into two stages: rough alignment and fine alignment, where the attitude matrix is ​​given by the rough alignment and the misalignment angle is generally not too large, ...

AI Technical Summary

Problems solved by technology

The coarse alignment method directly uses the measured value of the accelerometer, but the ship is affected by surge, sway, and heave under mooring conditions, and the accelerometer information is polluted, so the alignment effect is often not very good, and the misalignment Larger angle system error presents more serious nonlinear characteristics

However, the traditional fine alignment method (such as the second-order leveling method) often cannot meet the alignment accuracy requirements due to the influence of surge, sway, heave and large misalignment angle under mooring conditions.

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