Discrete-time adaptive control of a nonlinear aircraft flight dynamic system (NASA GTM) with damage

Abstract

This paper studies some key technical issues of discrete-time adaptive control of a continuous-time nonlinear aircraft flight system with uncertain structural damage. A linearized discrete-time aircraft model with a dynamics offset is obtained from the discretized nonlinear aircraft model, which characterizes large unknown system parametric and structural changes caused by structural damage. The invariance of the discrete-time infinite zero structure before and after damage is derived for small sampling periods. A state feedback MRAC scheme is designed to ensure the signal boundedness of the closed-loop system and asymptotic output tracking in the presence of the dynamics and damage uncertainties. This linearization-based discrete-time adaptive control scheme is evaluated on a high-fidelity continuous-time nonlinear aircraft model-the NASA generic transport model (GTM) with uncertain damage. Simulation results show the desired system performance and demonstrate the effectiveness of the developed discrete-time adaptive control scheme for the continuous-time nonlinear aircraft system.