The problems of developing of magnetic tracking signal transducers for augmented reality systems are considered. The spatial position of objects in such systems is carried out by measuring the vector of reference magnetic fields induction in the low-frequency spectrum of electromagnetic radiation. Small sensors and their 2D or 3D assemblies are mainly sensors and actuators in magnetic tracking sensor systems. Informative signals of magnetic tracking systems are described by functional dependencies, the main arguments of which are the distance between the actuator and sensor coils and the angles of their mutual inclination. To calculate the spatial position, signal models are used, which describe the distribution of magnetic fields generated by actuator coils and signals of sensor coils. The structure of the signal-processing chain of the programmable magnetic tracking system and its implementation based on PSoC family 5LP Family Cypress Semiconductor Corporation are presented. The results of experimental studies of signals family when changing the distance between the coils and the angles of their relative position are obtained. Taking into account experimental data the signal model describing functional dependences of informative signals is developed. The use of the presented signal model covers the tasks of development and specification of algorithms for calculating the spatial position, debugging and rapid assessment of the accuracy of the magnetic tracking system, optimization of calibration procedures and more. Approbation of the presented devices of magnetic tracking is carried out in numerous projects on development of augmented reality components in data fusion technology with a combination of signals of measuring converters of magnetic tracking and IMU modules based on MEMS 3D accelerometers and gyroscopes.
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