Magnetic Indoor Positioning

Magnetic indoor positioning involves the use of magnetometers and inertial measurement units to position pedestrians and robots in an indoor space. Most modern buildings are made of ferromagnetic materials like steel, which creates unique magnetic fields inside buildings. This principle enables positioning without any need for a building to have light or power.

 Map of expectation of the magnetic field vector computed using Loomis Laboratory UGV training data and Gaussian process regression.

The Magpie dataset

In this paper, we present a publicly available dataset for the evaluation of indoor positioning algorithms that use magnetic anomalies. Our dataset contains IMU and magnetometer measurements along with ground truth position measurements that have centimeter-level accuracy. To produce this dataset, we collected over 13 hours of data (51 kilometers of total distance traveled) from three different buildings.

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Experimental Evaluation of the planar assumption in magnetic positioning

Magnetic field-based indoor positioning methods often assume that the direction and magnitude of magnetic fields in buildings are invariant with height. We evaluate this assumption in this work by first analytically considering a single magnetic beam and subsequently measuring variations of the magnetic field with respect to height in two different scenes.