US Patent 9108747 Tool for accessing satellite fill/drain valves during propellant resupply

Herein is disclosed a tool, system and method for refueling on-orbit spacecraft. The tool and system are configured to allow for resupply of spacecraft configured to be propelled by either a bipropellant (oxidizer and fuel) or a monopropellant (typically hydrazine). The refueling tool is particularly suited for resupply of satellites not originally prepared for refueling but the system may also be used for satellites specifically designed for refueling.