Patent ID: 6993443

Claim:
A method for determining and tracking the changing, true position and orientation of a magnetic field sensor within a three-dimensional magnetic field space from measuring position and measuring orientation values measured by the magnetic field sensor, comprising: structuring the magnetic field space into a three-dimensional grid with equidistant grid points; successively measuring values with the magnetic field sensor with constant orientation while the magnetic filed sensor is positioned at each of the different grid points; storing the values in a calibration table as calibration positions and calibration orientations associated with real positions of the grid points in a real space coordinate system; determining four calibration positions from the calibration table that span a tetrahedron enclosing the measuring position in a calibration space coordinate system; and for continuously measured, actual measuring values from the magnetic field sensor, performing a linear interpolating transformation of the measuring position to the real space coordinate system based on the four calibration positions; and outputting the transformed measuring position as a true position of the magnetic field sensor.