Effects Analysis of Frozen Conditions for Spacecraft Relative Motion Dynamics


Aerospace Engineering, Malek-Ashtar University of Technology


The purpose of this rersearch is to analyze the effective application of particular earth orbits in dynamical modeling of relative motion problem between two spacecraft. One challenge in implementing these motions is maintaining the relations as it experiences orbital perturbations (zonal harmonics J2 and J3), most notably due to the Earth’s oblateness. Certain aspects of the orbital geometry can remain virtually fixed over extended periods of time due to a natural phenomenon called a frozen orbit. Specifically, the elements of the orbital geometry that can remain fixed are the argument of perigee (ω) and eccentricity (e). Simulation results show that, using these frozen orbits phenomenon results in considerable propellant saving and performance duration a relative orbital mission is preferable. In this regard, an method is developed that determines if the relative orbit conditions will be met given the initial differences in frozen orbit elements (argument of perigee and eccentricity) for each of two spacecraft. By using the frozen conditions in relative motion dynamics can be reduced the amount of required propellant for orbit correction manoeuvres due to the harmonic perturbations over the course of a year.