NASA Needs Robot Arms for High-Orbit Satellite Repairs
This artistic representation shows Canada's Dextre robot arm (right) performing a robotic refueling task on the space station.
NASA can't send astronauts to fix satellites or spacecraft that break down in very high orbit above the Earth. That's why the U.S. space agency has called for robotic arms that can help repair satellites latch onto any spacecraft in need of a tune-up or refueling.
A repair satellite might use two or three robot arms to capture and servicing another spacecraft, according to NASA's request for information issued today (March 9). Such life-extension repairs could enable space missions to stay alive in high geosynchronous orbits 22,000 miles (36,000 kilometers) above the Earth for years — a "sweet spot" orbit that allows spacecraft to match the Earth's rotation and stay in place over a certain spot.
The robotic repair missions are necessary because the high geosynchronous orbits were well beyond the range of NASA's now-retired space shuttle fleet. Space shuttle astronauts only ever went as far as the Hubble Space Telescope about 350 miles above the Earth.
Each robot arm could be about 7 to 10 feet (2 or 3 meters) long, and must have the mechanical strength to hold about 22 pounds (10 kilograms) in full Earth gravity. But the arms only need to be complete from the shoulder to the wrist, because NASA plans to attach its own tool drive system for the robotic arm hands.
The call for the robot arms came from NASA's Goddard Space Flight Center in Greenbelt, Md. That NASA center previously tested how medical consoles used in robotic surgeries on Earth could also help humans direct satellite repairs in space from thousands of miles away.
Experiments leading up to satellite refueling missions have also begun in space — the Canadian Space Agency's Dextre robot arm practiced retrieving tools built for robotic refueling missions during tests running aboard the International Space Station from March 7 to March 9.
Robot space "gas attendants" could also do much more than just service aging satellites someday. The U.S. military's DARPA research arm wants to look for ways to cannibalize old satellite junk to cobble together new working satellites in space.