US Patent 7225552 Method and system to detect an orientation of a moving object

Method and system to detect orientations of a moving object using one or more magnetic compasses. The method and system minimize magnetic field interference in a space where an object is moving such that the orientations of the moving object can be precisely detected. The method includes setting one or more earth magnetic field (EMF) conditions without a magnetic field interference component to determine whether the one or more magnetic compasses are located in an EMF area, calculating a magnitude of a magnetic field applied to the moving object using the one or more magnetic field compasses, and detecting an orientation of the moving object by determining whether the calculated magnitude of the magnetic field satisfies the one or more EMF conditions.