The inertial measurement unit is used in navigation systems or for orientation in space. It measures accelerations, angular rotations and the magnetic field in all three axes of the coordinate system. Data from all the sensors need to be combined to obtain accurate position measurements. The inertial measurement unit itself does not perform corrections with magnetometers and does not enable measurements of the deviation from the magnetic north. When influenced by external disturbances (iron, electromagnetic field, etc.) the magnetic field becomes distorted and has a magnetic deviation that needs to be eliminated. We therefore designed a program that eliminates this deviation. The program remembers the data received during the rotation of inertial measurement unit, draws the average ellipse (since the data are obtained in the form of an ellipse) and finally moves the ellipse to the centre of the coordinate system, rotates it and transforms it into a unit circle. That is how we got a matrix through which we perform corrections of the deviation from the magnetic north.
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