The invention relates to a device for measuring the position and the orientation of a mobile object with respect to a fixed structure, in a disturbed magnetic environment, of the type comprising:a first assembly of orthogonal coils (121 to 123) for emitting magnetic field(s), secured to the fixed structure,...http://www.google.co.uk/patents/US6754609?utm_source=gb-gplus-sharePatent US6754609 - Magnetic device and method for determining orientation
