Finite-time attitude control for fixed-wing UAVs with full-state constraints and input saturation

Abstract

This article addresses the attitude control problem for fixed-wing unmanned aerial vehicles (UAVs) under full-state constraints, input saturation, and matched/mismatched disturbances. Firstly, fixed-wing UAV attitude dynamics is established and a smooth model for input saturation is introduced to address the issue of magnitude limitations on control torques. Next, by virtue of the nonlinear transformation functions, the system under consideration is transformed into a constraint-free one. Then, a finite-time control strategy is presented by implementing the robust adaptive control technique and the backstepping approach. Under the influence of the derived finite-time control law, the attitude tracking errors of the closed-loop system affected by matched/mismatched disturbances can be reduced to a sufficiently small region near zero within a bounded time interval with the considered multiple constraints being agreed. Finally, by means of several numerical simulation examples, the validity of the derived control method is demonstrated.