Determining orientation using the earth's magnetic field

The structure and capabilities of the orientation device that uses the gravity vector and the Earth's magnetic field are considered. The device consists of three accelerometers and three magnetometrs, which are rigidly installed on the movable object. The possible characteristics of these sensitive elements, as well as the parameters of gravity and induction at a given point of the Earth (for example in Kiev). It are also shown the characteristics of devices AHRS. There are two algorithms for determining the magnetic course on the designated pitch and rolls: the algorithm of the triad and the Odintsov algorithm. Modeling shows that with relatively rough sensitive elements (accelerometers with an error more than 10 -2 m/s 2 , magnetometers with an error of more than 100 nT) it is advisable to use the triad method. With more accurate sensitive elements, the Odintsov method works better. When evaluating the characteristics, the systematic errors of the devices are taken into account, keeping in mind that noise interference are well filtered. Possible low - frequency interference when moving on the rough surface is not considered. The budget of errors for determining the true geographical course, which includes: errors of the сalculation of characteristics of the Earth's magnetic field parameters, magnetic deviation errors, seasonal and diligent variations of magnetic deviation, errors of magnetometers and accelerometers, as well as errors of algorithms.