IFOG technology for embedded GPS/INS applications

A spherical error probable of 4.0 meters was demonstrated with an IFOG-based, integrated inertial measurement/global positioning system under dynamic field conditions. Less than 1.0 nautical mile per hour free inertial mode drift was also achieved with this system under laboratory-simulated test conditions. To achieve these levels of performance, IFOGs with bias uncertainties less than 0.015 deg/hr, scale factor errors less than 50 ppm and angle random walks less than 0.005 deg/(root) hr wee required. The performance of a series of six IFOGs is reported. For comparison, the performance of the same instruments measured in two demonstration GGP units is also presented. Both laboratory and field test results of the systems are discussed. The focus of the data presented is the instrument noise and the long term bias thermal model stability. The instruments and systems were developed as part of the first phase of a two phase program to create a 100 in 3 integrated GPS/INS systems with a target cost of 15K dollars (US). With the implementation of interferometric fiber optic gyro technology, integrated guidance and navigation systems are potentially very low cost with high reliability and suitability for a wide range of military and commercial applications.