In this thesis a robust control for aircraft longitudinal motion is presented. The Model-Error Control Synthesis (MECS) is developed for this application, which consists of a nominal controller with a model error predictive filter. The control input is updated directly using the estimated model-error from the predictive filter to cancel the unmodeled dynamics or disturbance inputs. The Kalman filter is used to give a reliable state estimate and the predictive filer is used only to estimate the model error. The nominal control is chosen to be an LQR/dynamic inversion outer/inner loop controller for the longitudinal direction. The control law robustness to unmodeled dynamics and external disturbance is verified when MECS is active and not active. From various simulation results, MECS is shown to have better performance characteristics over the stand alone nominal control. |