Optical Navigation Systems

Abstract

A new navigation system has been developed in which an imaging sensor is used as an aid to an airborne integrated INS (Inertial Navigation System) and GPS (Global Positioning System) system. We name it the tightly coupled INS/GPS/EO (Electro Optical System) system. In the current configuration, the EO measures single ground object image position through a camera on board an aircraft. As represented by the term "tightly coupled", the INS, GPS and EO are integrated using the single Kalman filter which estimates aircraft states, sensor biases and ground object coordinates simultaneously. As the consequence, aircraft yaw angle determination (an weak point common in INS/GPS systems) is greatly improved. Furthermore, the INS/GPS/EO system can also focus on known stationary ground objects (control points) resulting in improved navigation accuracy.