Neptune Mission Design

As part of AE 700 Interplanetary Mission Design, we had a term project to produce a mission design as part of a team. I ended up leading a team working on an orbiter for a mission to Neptune. Our task was to design a mission that would leave Earth between 2030 and 2045, have a cruise time to Neptune of less than 30 years, and perform a 3-year mission investigating Triton, Neptune's rings, and the magnetic field.

I specifically worked on developing one of our baseline trajectories. We decided to investigate both a traditional gravity assist approach as well as a low thrust approach, of which I choose to work on the gravity assist option. To solve this problem I first found a candidate itinerary using Tisserand plots. I then implemented a genetic algorithm to optimize our trajectory using the itinerary and a cost function. This const function utilized lamberts problem shooting methods between each planetary flyby and includes the different of arriving and departing excess velocities to ensure a ballistic flyby. Both Earth departure excess velocity and Neptune arrival excess velocity were also included in the cost function in order to drive down energy requirements. The resulting solution is an energy-optimal, ballistic trajectory.