Functional Testing and Packaging of a Fluid Systems Servicer (FSS) for the International Space Station

The Fluid Systems Servicer (FSS) is designed to drain, purge, fill, and recirculate fluids while performing on-orbit start-up, scheduled and unscheduled maintenance for fluid lines leak check ports, and window assemblies on the International Space Station (ISS). The FSS will undergo extensive functional testing to verify that all design requirements have been met. The FSS will utilize space vacuum for purging operations on-orbit, thus providing vacuum back-filling capability with minimal power consumption. For ground testing, the application of space vacuum will be simulated. A full scale mock-up of the Space Station 20″ Window Assembly has been built for requirements verification. Two desiccator assembly Orbital Replacement Units (ORU)s will be tested to assure the FSS can perform window servicing requirements. The FSS gas/liquid separator fulfills an additional design requirement of removing gas bubbles from fluids with a static membrane separator. A functional test verifying gas removal has been devised. Several flex-lines and adapters which interface various ISS fluid line connectors via self-sealing Quick Disconnects (QD) are part of the FSS on-orbit kit. These Integrated Hose Assemblies (IHA)s and the desiccator assembly ORUs must be packaged, in addition to the FSS Fluid Control and Pump Assembly (FCPA) and the FSS Supply tank ORUs, for a safe launch and later stowage on-orbit.