OBSERVER BASED DYNAMIC SURFACE CONTROL OF A HYPERSONIC FLIGHT VEHICLE

摘要

This paper describes the design and analysis of a proportional integral air speed controllerand a nonlinear adaptive dynamic surface altitude controller for the longitudinal dynamics of a generichypersonic flight vehicle. The uncertain nonlinear functions in the pure feedback flight vehicle modelare approximated by using radial basis function neural networks. For the controller design, thecomplete states are assumed to be available for measurement, then a sliding mode observer isincorporated to estimate the states which are difficult to measure in practice. A detailed stabilityanalysis of the designed altitude controller shows that all the signals of the closed loop system areuniformly ultimately bounded. The robustness and performance of the designed controllers, with andwithout the observer are verified through numerical simulations of the flight vehicle model for trimmedcruise conditions of 110,000 ft and Mach 15.