It seems that in nearest future science fiction writers will be forced to try harder to earn for their “fiction” in name. DARPA announced on March 25, 2016, their new research program.
This time it will be truly creative and peaceful technology; it is called RSGS (Robotic Servicing of Geosynchronous Satellites) and is perfect solution for companies which are launching highly unique and expensive satellites to GEO orbit (around 36000 km from Earth). The idea is creating robotic spacecraft (called RSV – Robotic Servicing Vehicle) which will be able to fly to damaged or not working satellite and perform service: refuel satellite, change payload, swap broken part or help with jammed solar array.
Idea is not completely new. In previous years different companies and research organizations were trying to develop some kind of spacecraft which could serve as servicing space vehicle or refueling station. German space agency DLR developed Deutsche Orbitale Servicing Mission (DEOS) and contracted it with Astrium (Airbus Defence and Space) in 2012 for first launch in 2018. It is test satellite mainly objected for refueling other satellites in space. Another concept was Space Infrastructure Servicing (SIS) developed since 2011 (with launch planned for 2015) by Canadian Company MacDonald, Dettwiler and Associates. It was basically refueling satellite and it was planned to refuel one of the old Intelsat satellite on GEO orbit in first mission in 2015. Unfortunately program was cancelled due the lack of interest from potential customers; MDA claimed that DARPA was interested in the cooperation in SIS program but without any further agreements. NASA started to develop own project called Robotic Refueling Mission (RRM) with first refueling adapter delivered to International Space Station during STS-135 in 2011 and during Japanese HTV-4 mission in 2013. First successful refueling of satellite mockup was performed with RRM in 2013. Every conception was basically refueling robotic spacecraft with very limited abilities. DARPA started with something new – in spite of refueling, RSV will be able to perform minor repairs (like repairing jammed solar arrays or antennas), change some parts or payload, perform detailed observation of satellite or grab it and move into other position. Another novelty is modular construction – DARPA objective is to design only part of the satellite: software, modular toolkit and additional hardware with possibility of attaching it to every satellite bus. Most important part of the RSGS is robotic arm called FREND. It was designed to provide possibility of attaching satellite to RSV even if it is not equipped with docking port. FREND is equipped with multiple joints to provide large degree of movement and multiple points to attaching modular tools.
Whole program is based on public-private partnership – DARPA will provide launch service and tool module, private partner will provide satellite bus, integration, mission control center and qualified personnel. DARPA considers RSGS as big chance for whole space industry and long-awaited solution. According to RSGS program manager Gordon Roesler:
“The ability to safely and cooperatively service satellites in GEO would vastly expand public and private opportunities in space. It could enable entirely new spacecraft designs and operations, including on-orbit assembly and maintenance, which could dramatically lower construction and deployment costs while extending satellite utility, resilience and reliability… Commercial and government space operators have sought this capability for decades. By investing together, we can achieve a capability that would be extremely challenging to do individually.”
DARPA plans to find partner and create technology demonstrator in next five years.
On picture above You can see DLR DEOS mockup.