Publications Details

Model fidelity studies for rapid trajectory optimization

Hood, Lisa G.; Bennett, Gerard B.; Parish, Julie M.

The generation of optimal trajectories for test flights of hypersonic vehicles with highly nonlinear dynamics and complicated physical and path constraints is often time consuming and sometimes intractable for high-fidelity, software-in-the-loop vehicle models. Practical use of hypersonic vehicles requires the ability to rapidly generate a feasible and robust optimal trajectory. We propose a solution that involves interaction between an optimizer using a low fidelity 3-DOF vehicle model and feedback from vehicle simulations of varying fidelities, with the goal of rapidly converging to a solution trajectory for a hypersonic vehicle mission. Further computational efficiency is sought using aerodynamic surrogate models in place of aerodynamic coefficient look-up tables. We address the need for rapidly converging optimization by analyzing how model fidelity choice impacts the quality and speed of the resulting guidance solution.