US Patent 7511736 Augmented reality navigation system

A navigation system utilizing augmented reality is provided which utilizes captured images to generate orientation information, wherein the pitch, yaw and roll are periodically derived from an inexpensive sensor, and in-between the periodical update, the pitch, roll, and yaw information are derived by capturing and image of the observed scene, identifying reference image components (RIC's) in a images and comparing those RIC's with subsequently captured images, to derive orientation information.