Approximate controller design for singularly perturbed aircraft

Abstract

The purpose of this thesis was to extend the quasi-steady-state approximation and matrix block diagonalization methods utilized in the work of Shim and Sawan [1]. These authors showed that an approximate controller solution could be developed by relocating only the slow poles for two-time-scale aircraft dynamics. In addition, they showed that the difference between approximate solutions and exact solutions was bounded within limits as O(epsilon) and O(epsilon2). This technique was successfully applied to the lateral dynamics of the de Haviland Canada DHC-2 Beaver aircraft. In this thesis, the same technique was applied to the NASA F-8 aircraft dynamics in order to show that the method is not unique to the Beaver and can be applied to other aircraft models. It also extended the method to consider the singularly perturbed stochastic system and showed that a finite solution to the Lyapunov equation existed as a result of the stability.