Robust Cascaded Control with Antisaturation for Fixed-Wing Trajectory Tracking

In this paper, an unconventional fully nonlinear robust control method was proposed for fixed-wing aircraft to track time-parameterized trajectories, rather than merely following geometric paths as in traditional approaches. The proposed controller relies solely on real-time reference position from the commander (e.g., the leader aircraft in formation flight), without requiring predefined path information or velocity. Based on the robust cascaded control structure, a novel input–output dual clamp antisaturation algorithm is developed for robust compensators to address input saturation and attitude constraints of fixed-wing aircraft; a sideslip-assisted rule is designed to prevent initial undershoot in lateral dive maneuver. Moreover, the number of parameters that need manual tuning in the proposed controller does not exceed that of conventional Proportional–integral–derivative controllers. Theoretical analysis proves the robustness and stability of both the proposed controller and the antisaturation algorithm. Finally, numerical simulations on an F-16 aircraft model verify the effectiveness of the robust cascaded controller in tracking various trajectories.