A Discussion of GPS/INS Integration for Airborne Photogrammetric Applications

The concept of using integrated GPS/INS for precise aircraft positioning is discussed and the integration algorithm is briefly reviewed. Airborne tests jointly conducted by the University of the Federal Armed Forces, Germany, The University of Calgary, and the Rheinbraun Company, Germany are used to assess the accuracy of the integrated system. Two Trimble 4000SX receivers, an LTN 90–100 strapdown inertial system and a Zeiss RMK 15a/23 photogrammetric camera were used in the experiment allowing for a comparison of perspective centers of the camera determined from traditional photogrammetric techniques and from GPS/INS integration. Results show that decimetre accuracy is achievable. The accuracy of the integrated system for attitude determination is also assessed but a conclusive result is not possible at this time. Relative angular velocities between the camera and the INS may have caused discrepancies in the respective attitudes.