Attitude measuring method suitable for vehicle fiber AHRS (Attitude and Heading Reference System)

Abstract

The invention belongs to the technical field of inertial navigation and particularly relates to an attitude measuring method suitable for a vehicle fiber AHRS (Attitude and Heading Reference System). In the invention, a low-cost fiber AHRS based on a Kalman filter and a GPS (Global Positioning System) integrated navigation system are adopted to detect and insolate a GPS fault signal and ensure the reliability of a SINS (Ship's Inertial Navigation) / GPS integrated system before the initial alignment of the SINS. After the output of the GPS is effective, the difference values between the coarse angle, the north speed and the south speed output by the SINS with the corresponding information output by a GPS receiver are selected as observation quantities to form a three-dimensional observation equation. In the invention, the calculation speed can be greatly increased to realize the real-time filter calculation. Compared with a combined system using a speed and a position as observation quantities, the navigation accuracy of the vehicle fiber AHRS, particularly the accuracy of an attitude computer is greatly improved.

Description

technical field [0001] The invention relates to the technical field of inertial navigation, in particular to an attitude measurement method suitable for a vehicle-mounted optical fiber attitude system. It is especially suitable for vehicle-mounted platforms with high dynamics and high requirements for attitude accuracy. Background technique [0002] With the increasing application demand of vehicle navigation system in civil field, vehicle integrated navigation technology has developed rapidly in recent years. Low cost and reliable accuracy have become the basic requirements of users for civilian vehicle navigation systems. The GPS attitude determination system has the advantages of low cost, low power consumption, small size, and good long-term data stability; however, the GPS attitude determination system also has its own defects, such as low data update rate, poor short-term stability, and limited by the quality of GPS signals. In areas with severe occlusion and cycle s...

AI Technical Summary

Problems solved by technology

[0004] Because the various measurement methods of the carrier attitude of the original fiber optic gyroscope often use speed and position as observations, even if some methods use GPS speed and attitude information as observations, the evaluation accuracy of each parameter is higher. Compared with using GPS position and velocity information as reference information, the evaluation accuracy of attitude error has been greatly improved, but the evaluation accuracy of position and velocity error has not been significantly improved

After the introduction of GPS attitude information, the evaluation accuracy of the inertial navigation attitude error is obviously better than that without the introduction of attitude information, but it has little effect on the evaluation of position and speed, and there is no obvious improvement

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