Single-axle table calibration method for fiber optic gyro strapdown inertial navigation system

Abstract

The invention aims at providing a single-axle table calibration method for a fiber optic gyro strapdown inertial navigation system. The fiber optic gyro strapdown inertial navigation system is placed on a single-axle table, the fiber optic gyro strapdown inertial navigation system is electrified for preheating, the angular velocity outputted by a fiber optic gyro and the specific force outputted by a quartz flexible accelerometer are collected, then the single-axle table is controlled to rotate at 90 degrees counter-clockwise around a rotating shaft three times, the angular velocity outputted by the fiber optic gyro and the specific force outputted by the quartz flexible accelerometer at each time are respectively collected, and the drift of the fiber optic gyro in an x, y and z-axis coordinate system of an inertia device and the zero bias value of the quartz flexible accelerometer in the x, y and z-axis coordinate system of the inertia device are further obtained. The method can measure the drift of the fiber optic gyro and the zero bias value of the quartz flexible accelerometer by utilizing the single-axle table to rotate into different angular positions; furthermore, the calibration cost of the single-axle table is low, the steps are simple, and the single-axle table only needs to be placed on the ground during the calibration without a laboratory.

Description

technical field [0001] The invention relates to a calibration method in the field of navigation. Background technique [0002] Calibration technology is a method to improve the accuracy of inertial navigation system from the aspect of software. Calibration technology is essentially an error measurement technology. For the fiber optic gyroscope strapdown inertial navigation system, the so-called error compensation technology is to establish the error mathematical model of the fiber optic gyroscope and the quartz flexible accelerometer, and measure the model coefficients through certain experiments, and then determine the error mathematics of the fiber optic gyroscope and the quartz flexible accelerometer. Model. The current calibration methods all use a large three-axis test turntable to perform a pre-set calibration path. After the position measurement test, speed measurement test and zero correction measurement test, the drift, scale factor, and installation of the fiber ...

AI Technical Summary

Problems solved by technology

As a kind of turntable, the three-axis test turntable can perform attitude angle movement in three degrees of freedom, that is, it can reproduce all the attitude angle movement states of the carrier. The large three-axis test turntable has high angular position positioning accuracy and a wide speed range. There are many functions, but the disadvantage is that it is expensive (generally more than one million yuan), troublesome to install (requires a foundation of three to five meters), and cumbersome maintenance procedures

If used for more than four months, the accuracy cannot be guaranteed and recalibration is required

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