Application of nonlinear filtering to navigation system design using passive sensors

The problem of navigation system design for autonomous aircraft landing is addressed, New nonlinear filter structures are introduced to estimate the p osition and velocity of an aircraft with respect to a possibly moving landi ng site, such as a naval vessel, based on measurements provided by airborne vision and inertial sensors. By exploring the geometry of the navigation p roblem, the navigation filter dynamics are cast in the framework of linear parametrically varying systems (LPVs), Using this set-up, filter performanc e and stability are studied in an H-infinity setting by resorting to the th eory of linear matrix inequalities (LMIs), The design of nonlinear, regiona lly stable filters to meet adequate H-infinity performance measures is thus converted into that of determining the feasibility of a related set of LMI s and finding a solution to them, if it exists. This is done by using widel y available numerical tools that borrow from convex optimization techniques , The mathematical framework that is required for integrated vision/inertia l navigation system design is developed and a design example for an air veh icle landing on an aircraft carrier is detailed.