On Tuesday, the Defense Advanced Research Projects Agency (DARPA) announced the next stage in an ambitious project called Phoenix, which it hopes will bring about the first demonstration of robotic, in-orbit satellite servicing in 2015."[Phoenix is a] modest effort to increase the return-on-investment for DoD [Department of Defense] space missions," Dave Barnhart, a DARPA program manager, said at a recent press conference.

The servicing, however, won't involve the repair of an existing satellite—instead, Control System Product Price List,one that has already been retired will be scavenged for spare parts. If all goes well, the antenna (or aperture) of the defunct satellite will be linked with one or more small "satlets" that will return it to active duty.

It costs a lot of money to put something into geosynchronous orbit, and not everything that's been put there remains active. In many cases, Motion Test for 3-axis Parallel Robot,this is because of the failure or obsolescence of only some of their hardware, while other parts remain perfectly viable and functioning. (In fact, we already know they've functioned after launch and deployment.)