A novel adaptive backstepping control scheme based on invariant manifolds for unmanned aerial vehicles in the presence of some uncertainties in the aerodynamic coefficients is presented in this article. This scheme is used for command tracking of the angle of attack, the sideslip angle, and the bank angle of the aircraft. The control law has a modular structure, which consists of a control module and a recently developed non-linear estimator. The estimator is based on invariant manifolds, which allows for prescribed dynamics to be assigned to the estimation error. The adaptive backstepping control law combined with the estimator covers the entire flight envelope and does not require accurate aerodynamic parameters. The stability of the whole closed-loop system is analyzed using the Lyapunov stability theory. The full six-degree-of-freedom non-linear model of a small unmanned aerial vehicle is used to demonstrate the effectiveness of the proposed control law. The numerical simulation result shows that this method can yield satisfying command tracking despite some unknown aerodynamic parameters.
A Neural Network-Based Adaptive Backstepping Control Law With Covariance Resetting for Asymptotic Output Tracking of a CSTR Plant
