Design of the controller for an aircraft is presented. The design is based on the flatness property of a global model. The nonlinear altitude dependent aircraft model is derived using rigid body dynamics. With cetain global assumptions, which are valid in whole state space, it has been shown that the ideal aircraft model is differentially flat. Controller design is achieved by motion planning, feedback linearization, and stabilization around the desired trajectory. The reference trajectory is a nonplaner cuve which breaks the sound barrier. The control law is valid on the whole flight envelope and tracks reference trajectory not passing nearby singularities. The data for F4 fighter aircaft has been used for simulation. The array of aerodynamic coefficients has been interpolated by cubic spline. Simulation results illustrate the closed-loop system behavior showing satisfactory robustness with respect to parameter variations.
Mohammad Khalid Khan
February 20, 2000
Dresden,Germany