Barycenter Control Method for UAV Aerial Recovery Based on Appointed-Time Prescribed Performance Control

To address the issue of barycenter instability caused by aerodynamic interference in the composite structure formed after aerial recovery and docking of unmanned aerial vehicle (UAV), this paper proposes a composite control strategy combining fixed-time convergence and dynamic performance constraints. First, a force analysis is conducted on the composite system, and a nonlinear 6-DOF system model is established. Subsequently, a fixed-time predefined performance function is designed for the composite position loop, the dynamic error boundaries are constructed, and a center of mass control law for the composite position loop is established. Combined with a nonlinear disturbance observer for composite disturbance compensation, the system’s convergence rate is dynamically optimized. Subsequently, based on Lyapunov theory, the stability of the closed-loop system within the preset time is proven. Finally, relevant experimental simulations are conducted, and it is verified that this method can still maintain the coordinated optimization of overshoot suppression and error tracking under strong disturbances, providing a solution that balances theoretical rigor and engineering applicability for unmanned aerial vehicle autonomous recovery in complex disturbance environments.