Combination Of Optical Imaging-based Navigation Technology

With of the ability of anti-jamming and autonomous, electro-optical systems are playing more and more important part in the field of navigation. The integrated navigation system based on electro-optical system and SINS takes the full advantage of each system and is able to improve system performance greatly. By employing high-precision electro-optical sensor, the features are extracted and identified from real-time images to integrate SINS to provide a high-precision navigation system with the advantage of anti-jamming and autonomous ability.This dissertation investigates on the method of using electro-optical cameras to integrate SINS to realize high-precision navigation and landing guidance.First of all, in the procedure of aircraft landing guidance, the nearer the aircraft approaches the airport, the higher navigation precision is needed. The electro-optical system has high resolution and the advantage that measurement error decreases while the distance to objects is nearer, and as a result is suitable for Landing Guidance System. The research on the scheme of Landing Guidance System based on electro-optical sensors is carried on first. In the procedure of landing guidance, the camera must stare at the airport, so a rotation algorithm for electro-optical cameras using aircraft attitude and token deviation from the center of imaging plane is investigated. What's more, the state equation and measurement equation for Kalman filters are constructed to estimate system position and azimuth angle. Also, the flight control module is made to make sure that horizontal trail of the aircraft converges at the center of airport runway. The simulation results indicate that the electro-optical landing guidance scheme proposed is able to satisfy the need for the precision of aircraft landing.Secondly, a method using real-time images of landmarks to integrate SINS and realize high precision navigation is proposed, which provides an autonomous navigation system in the situation of radio navigation system dropouts. The discussion of system architecture is brought forth first. Then it focuses on the construction of the measurement model and the Kalman filter in order to estimate SINS errors. Because SINS position errors are too large to satisfy the initial states of the filter, algorithm for estimating of the initial position for the Kalman filter is proposed to speed up the convergence of the filter, and simulations for the algorithm are done. The resultsindicate that the system position precision improves greatly and is able to satisfy Kalman filter.Finally, the system simulation and analysis of the factors that matter system results such as the selection of landmarks, the parameters of cameras and the trajectory of aircraft is done to improve navigation precision, and some useful conclusions are given to provide a standard for the development of electro-optical systems. The simulation results indicate that the proposal is able to estimate the errors of SINS and is useful to improve the precision of the integrated system.