America has seen NASA land on the moon, fix the Hubble Space Telescope and roam on Mars' landscape—but they have yet to see NASA robotically refuel and repair a satellite that was never designed to be serviced in space. The Robotic Refueling Mission is the first step to making routine robotic servicing on orbit a reality.
Robotic refueling is challenging. Before a satellite leaves the ground, its technicians fill its fuel tank through a valve that is then triple-sealed and covered with a protective blanket—designed never to be accessed again.
RRM paves the way for a future robotic servicing mission by demonstrating that a remote-controlled robot can overcome these obstacles to service and refuel a satellite on orbit. RRM will also prove other robotic servicing tasks during its two years of operations.
The RRM demonstration consists of the "RRM module," the International Space Station's "Dextre" robot, and four RRM Tools.
The space station's twin-armed Canadian robot, "Dextre," acts as the skilled spacecraft refueling and servicing technician.
Remote-controlled by Mission Operators on Earth, Dextre will move towards the RRM module, which is covered with servicing-related activity boards and other components. Using four unique RRM tools, Dextre will cut and peel back protective thermal blankets, unscrew caps, access valves, and transfer fluid—demonstrating that a robot can do the tasks needed to service a satellite in orbit. It will also demonstrate general space robotic repair and servicing operations.
What is the Robotic Refueling Mission?
RRM Image Gallery.
[Above] Astronauts transfer RRM module from shuttle cargo bay to ISS  | Robotic Refueling Mission Fact Sheet [PDF] Learn about RRM's operations and objectives |
To meet the challenge of robotic refueling, the RRM development team assessed what tasks would be necessary for a robot to access the triple-sealed fuel valve of an orbiting satellite and refuel it, as well as perform other servicing tasks. They then developed the cube-shaped RRM module that breaks down each servicing activity into distinct, testable tasks and provides the components, activity boards, and tools to practice them.
The RRM module is about the size of a washing machine and weighs approximately 550 pounds, with dimensions of 33" by 43" by 45." RRM includes 0.45 gallon (1.7 liters) of ethanol that will be used to demonstrate fluid transfer in orbit. The module includes protective thermal blankets, caps, valves, simulated fuel, and other servicing-related spacecraft components.
Designed by the same team that developed astronaut tools for the Hubble Servicing Missions, the four unique RRM tools cut and manipulate wires, unscrew caps, open and close valves, and transfer fluid.
Built-in cameras with LEDs light the way for Dextre's controllers and give them a front-seat view of the tools' actions.
Now that the Robotic Refueling Mission (RRM) is securely mounted onto the International Space Station, the RRM Operations team is dedicating the next two years to demonstrating robotic servicing and refueling tasks using the RRM module and Dextre.
RRM operations began on September 6, 2011 and will continue through 2013.
RRM is a joint effort between NASA and the Canadian Space Agency (CSA).
The shuttle Atlantis carried RRM to the International Space Station on July 8, 2011 during STS-135, the final planned shuttle mission.
Once it arrived at the International Space Station, spacewalking astronauts Mike Fossum and Ron Garan transferred RRM onto a temporary platform on Dextre on July 12, 2011.
On September 2, 2011, Canadarm2 and the Dextre robot transferred RRM to its permanent location on space station, the ExPRESS (Expedite the Processing of Experiments to the Space Station) Logistics Carrier-4.
RRM operations will be entirely remote controlled by flight controllers at NASA's Goddard Space Flight Center in Greenbelt, Md., Johnson Space Center in Houston, Marshall Space Flight Center in Huntsville, Ala., and the CSA's control center in St. Hubert, Quebec.
Each RRM task requires a high level of robotic precision and demonstrates state-of-the-art technology, tools, and techniques.
RRM maneuvers, tools, and algorithms were tested and verified in the Goddard Satellite Servicing Demonstration Facility (GSSDF) in Greenbelt, Md.
RRM on Flicker