"Formation flight design for a LISA-like gravitational wave observatory" by Chihang Yang and Hao Zhang

Article Title

Formation flight design for a LISA-like gravitational wave observatory via Cascade optimization

Authors

Chihang Yang, Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences, Beijing 100094, China
Hao Zhang, Key Laboratory of Space Utilization, Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences,

Keywords

modified equinoctial orbit, elements, LISA, spacecraft formation flight, gravitational wave observatory, Monte–Carlo, multi-objective optimization

Abstract

Laser Interferometer Space Antenna (LISA) is a project to detect and measure gravitationalwaves. The project has three spacecraft flying in a formation of near equilateral triangle ina heliocentric orbit trailing Earth. Many sources of perturbations cause the configuration todeviate from the nominal. This paper studies the formation design problem for a LISA-likemission by considering ephemeris-based dynamics. This type of mission is well-known foraddressing several strict mission requirements under the realistic dynamics. The problem isformulated as optimizing multiple mission performance indices. It is observed that someindices are correlated with each other, whereas some indices have different sensitivitieswith respect to the semi-major axis. Therefore, the problem is transformed into a two-stepcascade single-objective optimization, in which the optimal solution of the first optimizationproblem is fed to the second optimization as initial value. In addition, the major perturbingcelestial bodies are picked up to make a simplified but accurate enough dynamics to speedup the optimization. Numerical examples verify the analysis and show the effectiveness ofthe optimization procedure. The influences of mission lifetime and spatial scales on theoptimal solutions are also presented.