US Patent 7571791 Device and method for self-aligning position reference system

A positioning system for a moveable platform comprising at least one active array comprised of at least one light emitting element for transmitting a binary encoded identification, where the encoding may be spatial or temporal, positioned at a known location, at least one camera for acquiring an image of the at least one active array, component for receiving the binary encoded identification from the image, component for processing the image to determine the position of the active array with respect to the moveable platform, and component for combining the received binary encoded identification and the determined position to calculate a position of the moveable platform.