Design of the Flight Dynamics Subsystem for the COMS Satellite Ground Control System

A multi-mission geostationary Earth orbit satellite, Communications, Ocean, and Meteorological Satellite (COMS) has three payloads including Ka-band communications, geostationary ocean sensing imager, and meteorological imager. COMS Satellite Ground Control System (SGCS) is the only system for monitor and control of the satellite in orbit. In order to fulfill the mission operations of the three payloads and spacecraft bus, COMS SGCS performs telemetry reception and processing, satellite tracking and ranging command generation and transmission, satellite mission planning, flight dynamics operations, and satellite simulation. Flight dynamics function is one of most important functions in SGCS. Flight Dynamics Subsystem (FDS) operations include spacecraft orbit determination, orbit prediction, event prediction, fuel accounting, station-keeping maneuver planning, and station-relocation maneuver planning. FDS also provides COMS specific operation related functions such as wheel off-loading, oscillator updating parameter calculation, sensor interference management, and Earth acquisition parameter calculation after emergency Sun reacquisition. All of the orbit dynamics functions in FDS consider twice a day thruster based wheel off-loading operations affecting the COMS orbit. In this paper, detailed design of the FDS in COMS SGCS is presented. An object oriented analysis and design methodology is applied.