MagneTrack: Magnetic Field Separation Method for Continuous and Simultaneous 1-DOF Tracking of Two-magnets

This paper presents a method to track two magnets using one magnetometer on a smart device (e.g., smartphone), which detects the locations of the magnets around the device. A magnetometer measures the overlapping data signals generated by the two magnets. Thus, a data-separation technique is required to separately track the continuous and simultaneous signals generated by the two magnets. In this study, we develop a separation algorithm based on nonnegative matrix factorization to continuously and simultaneously track two magnets, and then conduct an experiment to validate our concept. We then compare our method in both simulated and actual environments. In the actual environment, we observe real data signals arising from the two magnets on a magnetometer. Finally, we present example applications to demonstrate the use cases of our model in human-computer interaction systems.