A Heuristic Method for Determining Payload-to-Vehicle Assignment & Launch Order for Multi-Vehicle Exploration Campaigns

As space exploration campaign plans target more distant locations, requiring longer mission durations and a greater emphasis on sustainability, the logistics become increasingly complex. The necessity of establishing and optimizing the design of the space logistics vehicles as early as possible in the campaign planning cycle therefore becomes a high priority in order to avoid future delays due to inconsistencies between the vehicle designs and programmatic constraints. This creates a need for methods by which to analyze the impact of vehicle design on complex exploration logistics. Furthermore, long multi-mission campaigns might involve several logistics vehicles, the designs of which may evolve during the timeline of the campaign. Additionally, certain vehicles could only be available with certain frequencies or within defined periods. This creates a large decision space of payload assignments that would not be efficient to explore manually. This paper addresses this issue by proposing a method for planning and optimizing exploration campaign logistics for campaigns involving multiple logistics vehicle designs, whilst navigating programmatic requirements and constraints. The method is applied to the planned Commercial Lunar Payload Services (CLPS) and Artemis lunar exploration campaigns as case studies. In the CLPS analysis, a reduction in total mass-to-Low Earth Orbit (LEO) of 45.6% compared to the estimated baseline scenario is found.