There are many satellites in space whose fuel has about to come an end. Besides some satellites need to be repaired. So to repair and refuel the satellites without bringing them back to Earth, space agency NASA is developing a service robot. The robot will go to space, refuel the satellites and if needed will repair them.
When 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. At present, there are 275 commercial satellites at 22,300 miles (35,800 km) above the Earth in Geosynchronous Earth Orbit (in short GEO). These satellites play key roles in communications, science, defense and weather monitoring.
Tom Aranyos, technical integration manager in NASA’s Fluids and Propulsion Division at Kennedy said, “America depends on satellites in geosynchronous orbit.”
But the bitter truth is every satellite has its durability. If a satellite operates flawlessly for years after years without rest, then its performance starts degrading gradually; slowly but surely. And at certain time the satellite runs out of propellant and can no longer keep itself on station and properly work. Some of the satellites have come to be obsolete to perform perfectly. Besides, some satellites’ fuel has come to an end. Therefore these satellites need to be repaired and refuel to work perfectly.
And for that NASA’s Goddard Space Flight Center is working to develop orbital robots that can intercept, refuel and service geosynchronous satellites. In fact, Goddard wants to build such a robot that will be capable of carrying out 5 “Rs” – refueling, repositioning, remote survey, component replacement and repairing – on any satellite that might require its services.
Now, Engineers at the Kennedy Space Center in Florida are trying to find a way to safely and effectively refuel satellites using hypergolic propellants such as nitrogen tetroxide, hydrazine and monomethyl hydrazine. The engineers will develop a flight-ready pump and work out operating procedures. The test will begin next year. On the other side, the astronauts aboard the ISS are supposed to do a refueling demonstration later this year.