Adaptive dynamic surface control for aircraft flight path angle

For the feature that aircraft longitudinal dynamics include parametric uncertainties and external disturbances, an adaptive dynamic surface controller was proposed for flight path angle. Dynamic surface control method eliminated the problem of "explosion of complexity" existing in traditional backstepping approach with the introduction of low pass filters. Adaptive laws were designed to estimate unknown parameters of the model and nonlinear damping items were used to overcome the external disturbances. From Lyapunov stability analysis, it was shown that the control strategy guaranteed the semi-global stability of the closed-loop system, and made the tracking error arbitrarily small by adjusting the controller parameters. Simulation results indicate that the proposed scheme can make flight path angle track the desired trajectory with simplifying the control design procedure. The control system has strong adaptive capability and is robust to external disturbances.