NASA Goddard developed the Cooperative Service Valve (CSV) to facilitate the resupply of media, such as propellants and pressurants, to satellites. The CSV replaces a standard spacecraft fill and drain valve.
The CSV offers various advantages over standard service valves: a robotic interface, three individually actuated seals, a self-contained anti-back drive system, and built-in thermal isolation. When mounted to a spacecraft as designed, the CSV transfers all operational and induced robotic loads to the mounting structure. The anti-back drive mechanism prevents the CSV seal mechanism from inadvertent actuation. Alignment marks, thermal isolation, and a mechanical coupling capable of reacting operational and robotic loads optimize the CSV for telerobotic operation.
Unique keying of the mating interface prevents mixing of media where more than one configuration of the CSV is used. Color-coding and labels are also used to prevent operator error. The CSV has four configurations for different working fluids, all with essentially unchanged geometry and mechanics.
Spacecraft outfitted with the CSV enable in-orbit servicing with less risk, lower cost, and a much higher chance of success. The tools used to interface with the CSV, both on the ground and in space, were also designed and tested by NASA. The CSV architecture and approach is extensible to all space assets that could potentially be fueled/refueled on and off the ground including manned crew vehicles, planetary rovers, and space habitats.