AAS 99-126

Dynamics and Control of Cluster Orbits for Distributed Space Missions

C.C. Chao, J. Pollard, S. Janson

The Aerospace Corporation, Los Angeles, Ca

Abstract

Space missions in which the payload functions are distributed among several satellites may benefit from the use of cluster orbits where the satellites fly in a tightly locked formation with a relatively small required to maintain the cluster. This paper consists of two parts. Part I describes a method for determining the cluster orbital elements, and the relative geometry and dynamics of satellites under a two-body force field with the secular J2 influence. Part II examines the disruption of the formation due to all the major natural perturbations, and the feasibility of a formation-keeping strategy. The proposed strategy blends four state of the art techniques: differential GPS measurement, micro electromechanical systems, frozen orbits, and auto-feedback control. Results show that it only requires 10 to 30 m/s per year per satellite in to control a 1 km radius cluster for LEO.