Patent attributes
A vehicle guidance system for guiding a vehicle along a magnetic marker including a first magnetic sensor having a sensing axis, the first sensor measuring a first magnetic field. A second magnetic sensor has a sensing axis, the second sensor measuring a second magnetic field. The sensing axis of the second magnetic sensor crosses the sensing axis of the first magnetic sensor at a vehicle guide point. A processor is configured to receive data representative of the magnetic field measured by the first and second sensors and to calculate a lateral offset between the guide point and the magnetic marker based upon the measured magnetic fields. A method for guiding a vehicle in response to a marker having magnetic field is also disclosed. The steps of the method include measuring magnetic field strength proximate the marker, measuring ambient magnetic field strength remote from the marker, nulling the ambient magnetic field by removing the remote magnetic field strength from the proximate magnetic field strength, calculating a lateral displacement between the vehicle and the marker using the nulled magnetic field strength, and guiding the vehicle in response to the lateral displacement between the vehicle and the marker.
