Using critical docking avionics provided by Southwest Research Institute, the first Mission Extension Vehicle (MEV-1) successfully docked with a client satellite on February 25, 2020. SpaceLogistics, a wholly owned subsidiary of Northrop Grumman, selected SwRI’s Rendezvous and Docking Avionics Unit (RDAU) for its MEV-1 docking system.

MEV-1 is the industry’s first satellite life-extension vehicle, designed to dock to geostationary Earth-orbiting satellites nearly depleted of fuel. Once connected to its client satellite, MEV-1 uses its own thrusters and fuel supply to extend the satellite’s lifetime. When a satellite no longer needs service, MEV-1 will undock and move on to the next client satellite needing support. 

“Keeping satellites running beyond their typical 15-year design life is an efficiency measure,” said Larry McDaniel, who led the program in SwRI’s Space Science and Engineering Division. “There’s value in keeping satellites running beyond their typical 15-year design life when they are continuing to function well overall but are unable to maintain orbit unassisted.” 

The SwRI-developed RDAU manages critical, real-time information to facilitate MEV-1-satellite docking. The highly configurable, programmable data processing platform provides advanced on-orbit capabilities, including high-speed signal processing. The SwRI RDAU includes vision-processing capabilities, supporting multiple camera interfaces. This provides high-performance processing and field-programmable gate array (FPGA) platforms for camera-data routing and image processing. 

“We designed the RDAU with an image-processing FPGA that can be programmed in space,” McDaniel said. “Usually you can only program these on the ground, prior to launch. With our system, MEV-1 operators will be able to add new system capabilities by reconfiguring the FPGA on orbit, a first for this particular device.”

The 2,330-kilogram MEV-1 launched last October and has since been using its electric propulsion system to reach geostationary orbit. Now connected to the client satellite in a stacked configuration, the spacecraft will undergo a series of tests and checkouts. MEV-1 will then relocate the client satellite into geosynchronous equatorial orbit, allowing it to return to normal operation.

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