Ground speed testing methods suitable for optical fibre gyroscope strap-down inertial navigation system

Abstract

The invention relates to a ground speed detection method suitable for a fiber optic gyro strapdown inertial navigation system, and relates to a rowing compensation method. It solves the problem that the rowing effect affects the accuracy of ground speed detection in a high dynamic environment or a high frequency vibration environment. The present invention obtains the velocity measurement increment and the angle increment measurement value of the carrier relative to the inertial coordinate system by the specific force signal and the angular velocity signal respectively in the ground speed update period, and then obtains the velocity rotation item; at the same time, the specific force signal and the angular velocity signal The cross-product item of is fitted to obtain the rowing compensation item; the velocity increment of the carrier relative to the inertial coordinate system in the update cycle is calculated by the speed rotation item and the rowing compensation item, and then the obtained velocity increment is projected into the navigation coordinate system n, Calculate the speed increment caused by the acceleration of gravity and Coriolis acceleration in the navigation coordinate system n, and finally calculate the ground speed value through the basic equation of the inertial navigation system. The present invention is suitable for the situation that the carrier is in high frequency vibration or high maneuverability.

Description

technical field [0001] The invention relates to a ground speed detection method of an optical fiber gyro strapdown inertial navigation system. Background technique [0002] In a strapdown inertial navigation system, two key calculations are included. One is to update the calculation of the attitude of the carrier, and the other is to update the calculation of the ground speed of the carrier (the speed value of the navigation coordinate system n relative to the earth coordinate system). In the attitude update calculation, if there is a situation where the carrier angular velocity vector rotates, a coning error will be introduced. In the calculation of updating the ground speed of the carrier, the situation is more complicated, because to obtain the ground speed information of the carrier, it is necessary to integrate the force signal in the navigation reference coordinate system. This integration process is usually divided into two steps: first, The specific force signal se...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem that the rowing effect affects the system ground speed detection accuracy in a high dynamic environment or a high frequency vibration environment, the present invention provides a ground speed detection method suitable for the fiber optic gyro strapdown inertial navigation system

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