L1 Augmented Controller for a Lateral/Directional Maneuver of a Hypersonic Glider

Abstract

A lateral/directional maneuver of a hypersonic glider along a descent trajectory is presented. A pole placement controller is implemented as the baseline controller to carry out a pulsed bank maneuver of 25 deg. The baseline controller is augmented with a adaptive controller to cancel out the matched and unmatched uncertainties. The sources of uncertainties are reduced and asymmetrical control surface deflections, aerodynamic and gravimetric uncertainties, and control surface failure. The pole placement controller for the lateral/directional dynamics is a single-input/single-output system. The differences in terms of performance and robustness between the baseline and the augmented controllers are presented. The baseline controller shows good tracking under nominal conditions. However, there is a degradation in its performance in the presence of uncertainties and failures. The improvement in performance offered by the adaptive controller is presented with the help of the tracking error norm . In the process of improving the performance of the baseline controller, an increase in the control surface metric and deflection for the augmented controller is observed. The time delay margin shows that the use of adaptive augmentation reduces the robustness of the baseline controller.