High Accuracy INS based on Fiber Optical Gyroscope for AUV Application

This paper describes the high accuracy inertial navigation system (INS) for autonomous underwater vehicle application. Because fiber optical gyroscope (FOG) operational principle for sensing inertial rotation is not mechanical, but optical, FOG is inherently quick to start, resistant to shock and vibration, light, compact, and long live. These characteristics make it particularly suitable for strapdown attitude and heading reference system. Our laboratory develops the first self-designed INS based on fiber-optic gyroscope (FOG), which is designed to meet the very high positioning requirement for marine and underwater application. The paper focus on the issue of evaluating the performances of the system based on several scenarios including alignment errors and sensor errors. Several simulations have been done to evaluate INS performances, and results demonstrate it achieves very high performance. A further research topic is to discuss three different functional schemes of INS in terms of free-azimuth system, Foucault system, unipolar system. Moreover, detailed results of system simulation are depicted respectively.