PALO ALTO, Calif. – July 21, 2016 — Space Systems Loral (SSL), a leading provider of innovative satellites and spacecraft systems, today announced it has received $20.7 million from the Defense Advanced Research Projects Agency (DARPA) to design and build robotic arm flight hardware for the agency’s Robotic Servicing of Geosynchronous Satellites (RSGS) program. SSL is receiving the funds through MDA US Systems, a division of MDA managed by SSL, and is working with the U.S. Naval Research Laboratory (NRL), which is managing the robotic arm contract for the RSGS program. The contract is for two complete robotic arm systems, which would be able to carefully capture and berth with satellites that were not previously designed for docking. The robotic arms would each have multiple joints enabling dexterous movement and could carry and use multiple generic and mission-specific tools. Building on contracts announced in both 2012 and 2013 for prior DARPA research into space robotics, the total contract value awarded now stands at over $40 million, and could grow further if all remaining options are exercised.
DARPA satellite-servicing project comes under congressional firehttp://spacenews.com/darpa-satellite-servicing-project-comes-under-congressional-fire/
If we had an extra-terrestrial propellent source, orbital servicing bots would be more interesting. They could rendezvous with an unlimited number of sats. Two possible sources of extra-terrestrial propellent are the lunar poles and near earth carbonaceous ivunas.
A change in tone from Orbital (now Orbital ATK) after just a few short years. Then:http://spacenews.com/satellite-builders-not-enthusiastic-about-orbit-servicing-project/Now:http://spacenews.com/orbital-atk-sues-darpa-to-stop-ssl-from-winning-satellite-servicing-contract/Current status:http://spacenews.com/darpa-picks-ssl-as-satellite-servicing-partner-despite-orbital-atk-lawsuit/
New development: the Orbital-ATK lawsuit has been dismissed by the court:https://www.spaceintelreport.com/district-court-dismisses-orbital-atk-protest-darpa-satellite-servicing-program/
You could resupply a RSGS-like vehicle with fairly cheap launches, effectively an upper stage carrying a large hydrazine tank to GEO. Briz-M would do it.