Assessment of Constellation Designs for Earth observation: Application to the TROPICS mission
Garcia Buzzi, Pau
The orbit and constellation design process for Earth observation missions is complex and it involves trades between different metrics such as mission lifetime, instrument performance, coverage, cost, and risk among others. In this work, these figures of merit were utilized to support the orbit selection process used during Pre-Phase A and Phase A studies for the NASA-funded Time-Resolved Observations of Precipitation structure and storm Intensity (TROPICS) mission. Thousands of potential constellations were defined, simulated and compared with each other according to different mission coverage requirements. The sensitivity and robustness of figures of merit to various hypothetical operational failures (e.g., loss of one satellite or one launch) was systematically measured. A deployment strategy based on differential drag was described and analyzed. Finally, the orbital lifetime of various architectures was also studied with respect to NASA's 25 years de-orbiting recommendation. The contributions of this work include: (1) an exhaustive analysis of figures of merit commonly used in Earth observation orbit design, including a new metric called Continuous High-Revisit Coverage, which captures the long coverage gaps left by string-of-pearls constellations. (2) A methodology to assess robustness of constellations based on a brute-force disjoint scenario simulation approach (3) Results and recommendations from the mission analysis process for the TROPICS mission.
Constellation design; Coverage metrics; Mission analysis; Orbit selection; Satellite; Small satellites; Aerospace engineering
Selva Valero, Daniel
M.S., Aerospace Engineering
Master of Science
dissertation or thesis