Autonomous Navigation and Autonomous Orbit Control in Planetary Orbits as a Means of Reducing Operations Cost

* Copyright, 2003, Microcosm, Inc. Reprinted with permission. † Microcosm Inc., 401 Coral Circle, El Segundo, CA, 90245, [email protected] (310) 726-4100 ‡ “Stationkeeping” here means maintaining the satellite within a pre-defined control box (analogous to geosynchronous stationkeeping), not simply altitude maintenance which does not control the in-track phase and, therefore, does not allow the future positions of the satellite to be controlled or known. § As with autonov, absolute stationkeeping maintains the orbit with respect to inertial space and relative stationkeeping maintains it with respect to other satellites. For formation flying or rendezvous, relative stationkeeping is most appropriate. For constellations or single satellites, absolute stationkeeping has several disadvantages and no disadvantages that we are aware of. (See, for example, Wertz [2001], Sec. 13.4.1.) In this paper, we use autonomous stationkeeping or autonomous orbit control to mean absolute stationkeeping. ** The process of doing autonomous stationkeeping is covered by Microcosm patents No. 5,687,084 and 5,528,502. ABSTRACT