Background analysis:

Attitude and course measurement accidents are more common in the flight of UAVs. Such failures are highly concealed and difficult to find. They have always been a suspicious and difficult point in repair work. The high-precision attitude and course measurement of aerospace vehicles is mainly composed of a full attitude gyroscope, a magnetic induction sensor or an astronomical compass, and a full attitude indicator. Among them, the course angle and attitude angle are important flight control parameters of the aircraft and the application of the micro-inertial sensor and its combined measuring unit in the navigation and control system of the aircraft is gaining popularity. However, the measurement attitude of the micro-mechanical gyroscope will generate accumulative error due to random drift, and the use of an accelerometer to measure the attitude will be affected by the motion acceleration. Therefore, the aircraft needs to be upgraded and modified in the traditional inertial navigation system. The best solution is to use the composite micro-magnetic basic sensor to adjust the course of the aircraft, which is an inevitable trend to ensure the development of high-precision navigation. Guochuang Micro-magnetic Basic Sensor with high precision and sensitivity mounted on the aircraft is used to measure and collect the three-component and the total field intensity of the geomagnetic field for the adjustment and correction of the aircraft's course.

 Principle:

As the geomagnetic field vector in every position of the space can be determined from the geomagnetic field model, Guochuang three-component GMI magnetometer provided on the carrier is used to measure the projection of the geomagnetic field vector in the carrier's coordinate system in order to determine the course of the carrier. This is the basic principle of using Guochuang three-component GMI magnetometer to measure the course.

 Theory:

According to the geomagnetic field three-component GMI magnetometer projection, the magnetic course angle Φm expression of the UAV in any attitude can be obtained (the same as β in the figure below):

 

Where θ is the pitch angle: the angle between the x-axis of the airframe coordinate system and the horizontal plane; γ is the roll angle: the angle between the Y-axis of the airframe coordinate system and the vertical plane.

 

 

 Technical solution:

The attitude and course measurement system is mainly composed of a three-component micro-magnetic basic sensor array, a gyroscope and an accelerometer, and has the functions of attitude and course measurement.

 

 The main components of the system:

1. The attitude and course measurement system is composed of micro-magnetic basic sensor array, communication module, digital signal unit, etc.;

2. The micro-magnetic basic sensor array is installed where the magnetic interference of attitude and course measurement system is moderate;

3. Related algorithms include: carrier interference suppression, environmental noise suppression, magnetic course calculation, etc.;

4. Terminal console: display the working status and early warning information of the attitude and course measurement system.