DOI: https://doi.org/10.15368/theses.2020.161
Available at: https://digitalcommons.calpoly.edu/theses/2251
Date of Award
12-2020
Degree Name
MS in Aerospace Engineering
Department/Program
Aerospace Engineering
College
College of Engineering
Advisor
Kira Abercromby
Advisor Department
Aerospace Engineering
Advisor College
College of Engineering
Abstract
In interplanetary trajectory applications, it is common to design arrival trajectories based on B-plane target values. This targeting scheme, B-plane targeting, allows for specific target orbits to be obtained during mission design. A primary objective of this work was to implement B-plane targeting into the Spacecraft Trajectory Optimization Suite (STOpS). This work was based on the previous versions of STOpS done by Fitzgerald and Sheehan, however STOpS was redeveloped from MATLAB to python. This updated version of STOpS implements 3-dimensional computation, departure and arrival orbital phase modeling with patched conics, B-plane targeting, and a trajectory correction maneuver. The optimization process is done with three evolutionary algorithms implemented in an island model paradigm.
The algorithms and the island model were successfully verified with known optimization functions before being used in the orbital optimization cases. While the algorithms and island model are not new to this work, they were altered in this redevelopment of STOpS to closer relate to literature. This enhanced literature relation allows for easier comprehension of the both the formulation of the schemes and the code itself. With a validated optimization scheme, STOpS is able to compute near-optimal trajectories for numerous historical missions. New mission types were also easily implemented and modeled with STOpS. A trajectory correction maneuver was shown to further optimize the trajectories end conditions, when convergence was reached. The result is a versatile optimization scheme that is highly customization to the invested user, while remaining simple for novice users.