Complementary filtering attitude calculation method of navigation attitude reference system

Abstract

The invention relates to a complementary filtering attitude calculation method for a navigation attitude reference system, and the method comprises the steps: collecting gyroscope output, accelerationoutput and magnetometer output, and carrying out the normalization; carrying out horizontal alignment by utilizing the first group of accelerometer data, calculating a pitch angle theta, a roll anglegamma and an attitude conversion matrix from the system to a horizontal system, carrying out azimuth alignment by utilizing the first group of magnetometer data, calculating an initial course angle,and acquiring gyroscope output, acceleration output and magnetometer output data; calculating a gyroscope error by utilizing the acceleration and magnetometer output data, calculating a magnetic fieldintensity reference value of a local navigation system, and calculating a projection value fn of acceleration output on the navigation system; calculating an acceleration crossover result fX, calculating a magnetic vector crossover result calculation error, calculating a gyroscope data error correction value, and updating the attitude after output correction of the gyroscope; and calculating an attitude angle according to the updated attitude information.

Description

technical field [0001] The invention relates to navigation technology, in particular to a complementary filter attitude calculation method of a heading attitude reference system. Background technique [0002] With the development of smart manufacturing and cutting-edge chips, drones are widely used in both military and civilian fields. In order to obtain stable UAV flight control, the navigation system has become one of the indispensable airborne equipment. In general, the navigation system consists of inertial navigation and satellite navigation with sensors such as magnetometers. Under normal circumstances, the navigation system can continuously provide position, velocity and attitude angle (attitude angle includes pitch angle, roll angle and heading angle). However, because the satellite navigation system is susceptible to interference and signal interruption, in order to ensure the safety of the aircraft, it is necessary to use the attitude reference system as the airc...

AI Technical Summary

Problems solved by technology

First, according to the magnetic field distribution characteristics, the eastward magnetic field component is 0, and the traditional complementary filter attitude calculation method initializes all attitude angles to 0. Considering the cross product calculation method, when the heading angle is 180°, the magnetometer loses The correction effect on the heading angle, there is a correction blind spot

Especially when the initial orientation is 180°, the heading angle calculated by the attitude reference system will always remain at 0°, and the result of the attitude angle calculation is wrong

Second, the cross product results of the magnetometer are directly fed back to the three axes of the system, and the gyroscopes of the three axes are simultaneously corrected in the system, and the measurement error of the magnetometer is coupled into the calculation of the pitch angle and roll angle, resulting in pitch Calculation error of angle and roll angle

First, according to the magnetic field distribution characteristics, the eastward magnetic field component is 0, and the traditional complementary filter attitude calculation method initializes all attitude angles to 0. Considering the cross product calculation method, when the heading angle is 180°, the magnetometer loses The correction effect on the heading angle, there is a correction blind spot

Especially when the initial orientation is 180°, the heading angle calculated by the attitude reference system will always remain at 0°, and the result of the attitude angle calculation is wrong

Second, the cross product results of the magnetometer are directly fed back to the three axes of the system, and the gyroscopes of the three axes are simultaneously corrected in the system, and the measurement error of the magnetometer is coupled into the calculation of the pitch angle and roll angle, resulting in pitch Calculation error of angle and roll angle

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