Formation flight design using natural dynamics for halo orbiting and earth orbiting spacecraft

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2020-9
Kutlu, Aykut
This thesis presents the studies performed for spacecraft formation flight design and analyses. Two main design problems are addressed in this thesis: First the formation flight design of satellites flying near Sun-Earth collinear libration points; the second the formation flight design of satellites flying at Low Earth Orbit. Thus, formation flight design near Sun-Earth L1 and L2 libration points is investigated first, where solar radiation pressure as well as the gravitational disturbances of the planets are taken into account, for different Julian dates. The periodicity of the relative motion in formation flight is taken as a design criterion and convenient initial conditions are computed for each deputy satellite for desired formation configuration. It is desired that the required formation is maintained without the need of any correction maneuvers for formation keeping. In the second part, the method presented in this thesis for formation flight design is applied to Low Earth Orbit satellites. The results are also compared to the results obtained using current methods available in the literature. Results show that proposed method gives more consistent results and provides flexibility on the orbit design for formation in terms of formation keeping and fuel consumption needs as compared with the currently available methods. Finally, it can be stated that the trajectory and orbit computations done using the method presented in this thesis provide long term formation flight for space missions at L1, L2 libration points and for Low Earth Orbit missions. The main contribution of this method is the inclusion of all disturbancing forces acting on the satellite as a time variant discrete model. The initial conditions are found iteratively that ensures the periodic trajectory. Here, the usage of time variant discrete model to obtain periodic relative motion is a feature that distinguishes the current study from the existing methods in the literature.

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Citation Formats
A. Kutlu, “Formation flight design using natural dynamics for halo orbiting and earth orbiting spacecraft,” Ph.D. - Doctoral Program, Middle East Technical University, 2020.