Document Type
Article
Publication Date
2022
Journal Article Version
Accepted Manuscript
First Page
1
Last Page
17
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Abstract
Spacecraft constellations continue to grow in numbers, capability, and sophistication, requiring in creased levels of automation to properly cooperate in achieving their objectives. This paper develops a constellation scheduling capability for collecting images of points of interest (POI) and communicating the imagery data through the constellation to established ground station terminals. Various levels of coordination are considered. First, satellites coordinate to avoid duplicate efforts for imaging POIs; second, ground stations only service a single satellite at a time for downlinking; and third, satellites may crosslink data within the constellation to enable a more timely delivery of high-valued information as well as to increase the productivity of downlinking tasks for any particular satellite. The planning for constellation coordination is performed using a bi-level network flow approach. The first level of the planning creates a communication plan. A directed acyclic graph is formulated with nodes corresponding to a downlink or crosslink task at a given time. Heuristics are used to calculate the opportunity costs for spending time communicating versus collecting imagery. A mixed integer linear program (MILP) is solved to create a communication plan. The communication plan is then passed to a POI collection planner, which schedules imagery collection between existing communication time windows. Again, a network flow approach is used to simultaneously obtain a plan for each satellite. The bi-level framework considers task fulfillment opportunity windows as well as spatial constraints for task execution. The planning technique is demonstrated for a mission of 100 satellites to illustrate its capability and performance.
Recommended Citation
Cox, Skylar; Whitaker, Justin; Humble, John; and Droge, Greg, "A Two-Layer Constellation Scheduling Approach for Imaging and Communication" (2022). Space Dynamics Laboratory Publications. Paper 325.
https://digitalcommons.usu.edu/sdl_pubs/325