Transfer Alignment Of SINS For Airborne Missiles

Airborne missiles have been an important forcus in the airborn weapon family because of its characteristics of flexibility and fast responsibility, which lets it play a significant role in regin war. The firing accuracy and speed of missiles are mostly decided by transfer alignment technique. In view of this, the dissertation with application background of airborne weapons makes a deep study as the main application of airborne missiles background, transfer alignment from a substantial measure of observerbility analysis of states in transfer alignment error model, fast and accurate alignment matching algorithms, robust filtering algorithm and compensation of significant errors and so on.As the error covariance methods require complex kalman filter computes to get the estimated effect of the state variables, and singular value method of degree of oberservability analysis based on PWCS (Piece Wise Constant System) could get degree of observability of state variables before complex Kalman filtering computes. In the foundation of traditional observability analysis, a novel definition of degree of observability is proposed. This method could get the improvements of degree of observability of certain state variable in different maneuvers. It's more clear, intuitive and easy to design maneuvers. The analysis shows rocking wing maneuvers used in the following sections.In view of high-dynamic characteristics of the environment of airborne missiles, velocity or position matching method are no longer satisfy the system requirements. According to the different forms of attitude information in inertial navigation systems, the thesis deduced three matching algorithms based on attitude information and compared their estimated effect with simulations, particularly the principles in choice of attitude matrix elements were proposed when attitude matrix was chosen as measurements. On this basis, the "velocity and attitude matrix multiplication" matching algorithm was proposed, simulation results present that the new method has obvious advantages compared to other methodsBased on state estimation theory in Krein space, Kalman filter and H∞filtering formulas in Krein space were deduced and an adaptive H∞filter in Krein space was proposed which implements to the Krein space filtering theory. Simulations were done to compare the filtering performance in different noise conditions; the results show that the adaptive H∞filter in Krein space is more robust than Kalman filter and more accurate than H∞filter.Error effects such as lever arm effect, wing flexure and time delay between the two inertial navigation systems were studied in real application environment of airborne missiles.Detailed analysis of error mechanism and detailed mathematical description of the error term were deduced. Since the limitations of compensation lever arm effect method in practice, which needs know lever arm length and the information of angular motions, the impact to estimated effect of the three-axis lever arm lengthes with different maneuvers were analyzed. The analysis provides a theoretical basis and an important reference for the estimation of lever arm length effectively. After compared to the former compensation method, the advantages and disadvantages of the two methods were obtained; In view of the complexity of the wing aerodynamic characteristics of aircraft when maneuvers, the elastic deformation angles as time varying was put into account and which lets to present a real-time estimation scheme. Simulation results show that the deformation angles can be accurately tracked.Finally, focusing on time delay error of the two inertial systems, a practical error dealing method with the unknown time delay practically proposed, and effectiveness was illustrated through a turn maneuver. This method can overcome the time delay error of harmful interference, and avoid tedious of estimation for the delay time in time.