Operation Concept of the Precise Autonomous Orbit Keeping Experiment on the PRISMA Mission

PRISMA is a small-satellite formation flying mission created by the Swedish Na-tional Space Board (SNSB) with the Swedish Space Corporation (SSC) as prime which serves as a test platform for autonomous formation flying and rendezvous of spacecraft. DLR’s key contributions comprise the on-board GPS-based absolute and relative navi-gation system hardware and software, the on-ground Precise Orbit Determination (POD) layer, the Spaceborne Autonomous Formation Flying Experiment (SAFE) and the Autonomous Orbit Keeping (AOK) experiment. At the end of the mission after the formation release and evaporation, the AOK on-board software shall demonstrate MANGO satellite autonomous orbit control using a guidance law for the orbit’s Longi-tude of Ascending Node (LAN) using GPS-based absolute navigation data. The operation concept of the AOK experiment is presented. A key aspect considered is the on-ground generation and upload of the reference orbit. AOK will base the control of the real LAN to a reference orbit’s LAN. An example of experiment schedule is de-scribed in detail. An overview is given of the innovative and flexible PRISMA operations concept and of the DLR’s PRISMA Experiment Control Center (ECC).