Engineering Commons^™

Interplanetary Mission Design With Applications To Guidance And Optimal Control Of Aero-Assisted Trajectories, Peter J. Edelman

Open Access Dissertations

A method for finding optimal aerogravity-assist tours of the solar system is developed using indirect methods. Two cost functionals are used in the optimization; finding the minimum required maximum lift-to-drag ratio, with and without a convective heating-rate path constraint, and the path which provides the minimum total stagnation point convective heat load. It is found that using present or near-future thermal protection system materials will suffice for certain aerogravity assist trajectories at Mars. Minimum heat load optimal trajectories are found for aerocapture maneuvers at Uranus and Neptune. With a large radius, and short rotational periods, atmospheric rotation must be taken …

Analytical Methods For Gravity-Assist Tour Design, Nathan J. Strange

Open Access Dissertations

This dissertation develops analytical methods for the design of gravity-assist space- craft trajectories. Such trajectories are commonly employed by planetary science missions to reach Mercury or the Outer Planets. They may also be used at the Outer Planets for the design of science tours with multiple flybys of those planets’ moons. Recent work has also shown applicability to new missions concepts such as NASA’s Asteroid Redirect Mission.

This work is based in the theory of patched conics. This document applies rigor to the concept of pumping (i.e. using gravity assists to change orbital energy) and cranking (i.e. using gravity assists …