Real-time Trajectory Optimization of Impaired Aircraft based on Steady State Manoeuvres
<|reference_start|>Real-time Trajectory Optimization of Impaired Aircraft based on Steady State Manoeuvres: Aircraft failures alter dynamics, diminishing manoeuvrability. Such manoeuvring flight envelope variations, governed by the aircraft's complex nonlinear dynamics, are unpredictable by pilots and existing flight management systems. To prevent in-flight Loss of Control, post-failure trajectories must be optimal, planned in real-time, avoid terrain, and adhere to the impaired aircraft's reduced manoeuvrability and dynamic constraints. This paper presents a novel real-time trajectory optimization method for impaired aircraft based on a combination of differential flatness theory, the pseudospectral method, nonlinear programming, and inverse dynamics. In the proposed method, which utilizes a high-fidelity nonlinear six degree-of-freedom model, to conform to aircraft's altered dynamics a sequence of trim points is selected from the impaired aircraft's manoeuvring flight envelope based on the chosen optimization criteria, ensuring that the resulting three-dimensional trajectory observes terrain avoidance. Then, the required control inputs are obtained for each manoeuvre in less than a second. The method is applied to the NASA Generic Transport Model with rudder failure near a complex mountainous terrain. Both an optimal one-piece trajectory and a near-optimal piecewise path consisting of several optimal trajectories, are generated in non-real-time and real-time, respectively, and compared. Results show that the near-optimal real-time trajectory retains up to 80% of the optimality.<|reference_end|>
@article{norouzi2024real-time,
    title={Real-time Trajectory Optimization of Impaired Aircraft based on Steady
  State Manoeuvres},
    author={Ramin Norouzi, Amirreza Kosari, Mark H. Lowenberg},
    journal={arXiv preprint arXiv:2408.02316},
    year={2024},
    archivePrefix={arXiv},
    eprint={2408.02316},
    primaryClass={eess.SY cs.SY}
}