A high-precision transition trajectory optimization and control method for shipborne VTOL aircraft

A high-precision transition trajectory optimization and control method for shipborne Vertical Take-off and Landing (VTOL) aircraft is proposed to address the strong coupling nonlinearity between the propulsion system and aerodynamic forces during the transition process, and the sudden change in aerodynamic coefficients caused by the closure of the lift fan inlet hatch at the end of the transition. Firstly, considering the complex actuation structure and the influence of the lift fan inlet hatch, a transition model of the shipborne VTOL aircraft is established based on wind tunnel experimental data. Secondly, the attainable equilibrium set method is used to draw the transition corridor and transition objectives are defined based on corridor boundaries, aircraft dynamic constraints, transition height, and transition time as safety and performance indicators, and an optimization problem is established to solve the optimal transition trajectory using adaptive pseudo-spectral method. Finally, a Preset Time Disturbance Observer of Incremental Nonlinear Dynamic Inversion (PTDO-INDI) method is designed for aircraft control. This method can observe disturbances at preset times, overcome uncertain disturbances, and improve robustness. Simulation and semi physical verification show that the proposed method achieves the optimization of the transition trajectory of shipborne VTOL aircraft and accurate tracking of the optimal trajectory, while effectively suppressing disturbance effects, achieving high-precision transition goals that balance safety and performance.