Abstract: A guidance system for a self-guided vehicle features an electrical conductor and permanent magnets embedded together in an elongate groove formed in a vehicle-supporting surface such as a factory or warehouse floor. The electrical conductor provides steering guidance while the permanent magnets embedded with the conductor provide other information without distorting the magnetic field of the electrical conductor. To prevent such distortion, the permanent magnets are selected for their low magnetic permeability and high electrical resistivity. Magnetic field sensors are provided on the vehicle for determining exact position of the vehicle along its path of travel by sensing deviation, or lack thereof, with respect to such permanent magnets.

Abstract: A method and apparatus for determining the location of a target surface by projecting a periodically scanning pattern of light onto the target surface, and comparing the time of projection of a predetermined point of the pattern along a predetermined path with the time of observing an image of the predetermined point of the pattern reflected along an intersecting receiver path. An apertured disc is rotated between a light source and a collimating projection lens assembly to produce scanning pattern of light. Photoelectric sensors generate reference and receiver electrical signals in response to projection and reception of the pattern of light, and the distance of the target surface from a reference location may be electrically determined as a geometrically defined function of the phase angle between the electrical signals.