An Adaptive Controller for Very Flexible Aircraft

Abstract

Recently, a high-order linearized generic Very Flexible Aircraft (VFA) model that captures both flight dynamics and body elastic effects has been released to the public domain. To solve the control challenge for such state inaccessible plant, a new output-feedback adaptive controller for a general multiple-input-multipleoutput (MIMO) plant is developed in this paper. The proposed controller is able to fly the VFA model under two types of model uncertainties, i.e. plant uncertainties and actuator anomalies, which commonly exist for a long endurance flight. The first step towards the solution is the development of a reduced-order model. Based on the model, a baseline linear LQG controller is applied for the flight under nominal conditions. Then an adaptive controller is designed and added to the baseline for the additional robustness against uncertainties. Simulation results show the adaptive controller provides improved transient response and tracking stability compared with the baseline controller when subject to a large magnitude of the uncertainty.