A Full Span Magnetic Localization Algorithm

Magnetic dipole is a conventional model for the localization of a magnet. However, a restriction is that the distance from the test field point to the magnet’s position must be long enough comparing with the length of the magnet. Otherwise, the dipole model is inaccurate, which is known as the near-field problem. In this paper, we investigated the near-field magnetic density distribution for a circular ring magnet with respect to the magnet’s center, which is simply symmetrical about the magnet’s main axis, so it is in 2 dimensions. Further, we propose the full span (including near-field) localization algorithm on this distribution, which minimizes the calculation error between the measured flux densities and those calculated from the spatial and rotation transforms from the global coordinate system to the magnet’s coordinate system, so as to compute the magnetic density on the 2D field density distribution. Simulation results show that the proposed method can accurately to obtain the magnet’s position and orientation in near-field.