Automated Generation of Realistic Near-Optimal Aircraft Trajectories

A new approach toward the automated solution of realistic near-optimal aircraft trajectories is introduced and implemented in a software package named Ace. In the approach, the optimal open-loop trajectory for a three-degree-of-freedom aircraft model is first solved by using direct multiple shooting. Then the obtained trajectory is inverse-simulated with a more sophisticated five-degree-of-freedom performance model by using an integration inverse method based on Newton's iteration. The trajectories are evaluated visually and by analyzing errors between the trajectories. If the errors remain within a suitable application-specific tolerance, the inverse-simulated trajectory can be considered to be a realistic near-optimal trajectory that could be flown by a real aircraft. Otherwise, the parameters affecting the optimization and inverse simulation are altered and the computations are repeated. The example implementation of the approach, the Ace software, contains a graphical user interface that provides a user-oriented way to analyze aircraft minimum time and missile avoidance problems. In the software, the computation of the optimal and inverse-simulated trajectories is fully automated. The approach is demonstrated with numerical examples by using Ace.