Method for calculating aircraft attitude through utilization of geomagnetic information and accelerometer

Abstract

The invention provides a method for calculating an aircraft attitude through utilization of geomagnetic information and an accelerometer. Measurement errors of a magnetoresistive sensor and the accelerometer are taken as weight, and a measurement noise covariance matrix which is determined according to change of an included angle between an aircraft longitudinal axis and a geomagnetic vector is adjusted, thereby realizing the optimum estimation of an aircraft roll angle. According to the method, through matching of the geomagnetic information and the accelerometer, influence of an aircraft measurement blind area can be eliminated.

Description

technical field [0001] The invention relates to a method for calculating the attitude of a flying object by using geomagnetic information and an accelerometer, in particular to a method for calculating the spatial blind area and inherent deviation of the roll angle of the flying object by using the geomagnetic information and the accelerometer. Background technique [0002] The earth is a natural magnet, which is similar to a dipole placed at the center of the earth. Any point on the ground has a certain magnetic field strength and direction, so the geomagnetic field can be considered as a known vector field. According to the principle of vector attitude determination, if the direction of the geomagnetic vector can be measured by the sensor fixed on the aircraft, the attitude angle of the aircraft can be calculated by vector calculation. Due to its small size, low cost, and high overload resistance, the magnetoresistive sensor is widely used in the roll attitude measurement...

AI Technical Summary

Problems solved by technology

Even if the measurement accuracy of the magnetoresistive sensor reaches an ideal state, when the angle between the projectile axis and the magnetic north is small, the error in the calculation of the roll angle will tend to a certain extent due to errors in the measurement of the pitch angle and yaw angle. to diverge

[0005] The inventors found that for low-speed rolling flying objects, such as missiles and satellites, when the angle between the launching direction and the magnetic north direction is small, there will be a blind area when using the geomagnetic sensor to calculate the roll angle.

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