This thesis investigates the operation and calibration of a prototype electronic compass (e-compass) based on measurements of the Earth’s geomagnetic field. The first part presents the fundamentals of magnetism and the Earth’s magnetic field, as well as the differences between magnetic and geographic north, which affect the determination of the true heading. The two sensors, most commonly used in e-compass systems, namely the magnetometer and the accelerometer, are discussed, including their characteristics and limitations. The combined LSM303AGR sensor, which integrates a magnetometer and an accelerometer, is analyzed using MEMS Studio software. Measurements of individual axes are evaluated. From these measurements, offsets caused by magnetic disturbances and sensor characteristics are determined. Based on the acquired knowledge, an e-compass prototype is designed and implemented, enabling data acquisition, tilt compensation using the accelerometer, calibration of hard-iron distortions, and calculation of both magnetic and true azimuth. The developed prototype provides a comprehensive insight into the operation of an e-compass as a measurement system and highlights the importance of proper data processing and calibration for reliable heading determination. The thesis also examines whether the prototype can be used to determine the orientation of traffic signs. Experimental measurements showed that, when properly calibrated, the prototype determines orientation with sufficient accuracy, so such use is technically feasible. However, practical use is not entirely straightforward, because the local environment affects the measured orientation and each e-compass would have to be calibrated at its installation site. Before actual use, the practicality and reliability of the e-compass in a real environment should be further verified.
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