Thermal Design of the ORBCOMM Constellation Spacecraft

The thermal design strategy is discussed as it relates to the production of up to 34 identical small satellites in a relatively short period of time. Tight production and launch schedules and the need to design for low mass, risk, and cost presented a design challenge for all disciplines. A specific arrangement of passive thermal control features, including ITO-coated AgTef covered structure radiators, MLI, and software controlled heaters established a robust design. Thermal modeling of the bus and unique antenna are presented including a comparison between the predicted and required component temperature ranges. Also described are the primary mission objective, the spacecraft configuration, requirements and design drivers, mission environments, and design parameters.