Engineers at the U.S. Naval Research Laboratory's (NRL) Naval Center for Space Technology (NCST) recently completed robotic payload component level testing for the Defense Advanced Research Projects Agency (DARPA) Robotic Servicing of Geosynchronous Satellites (RSGS) program.
Once on-orbit, the RSGS robotic servicing vehicle will inspect and service satellites in Geosynchronous Earth Orbit (GEO), where hundreds of satellites provide communications, weather monitoring, support national security missions, and other vital functions.
The RSGS program is a public-private partnership between DARPA and Northrop Grumman's SpaceLogistics subsidiary, with NRL developing the robotic servicing payload.
[...] The RSGS payload includes flight hardware components, robotic control algorithms, multiple highly customized electronics designs, and flight software running on five single-board computers. NRL also specified and procured two dexterous seven-degree-of-freedom robotic arms, outfitting them with control electronics, cameras, lights, and a robotic tool changer.
Additionally, NRL developed the robotic tool to grapple customer satellites via their standard launch vehicle interface and procured another tool to capture resupply elements that are compatible with DARPA's Payload Orbital Delivery (POD) design standard.
[...] During TVAC testing, the robotic arm system demonstrated performance over temperatures representing actual on-orbit conditions. Under the harsh temperature and vacuum conditions of space, the robot arm performed a variety of operations including running pre-planned robotic calibration movements, tool actuation, and camera and light functions.
[...] The flight software team is preparing to start qualification testing. Testing takes place in a software testbed with a real-time dynamic simulation that generates simulated robot arm pose inputs for the robotic control algorithms and dynamic imagery for input into machine vision algorithms. This testbed allows the NRL team to test the flight algorithms with realistic control loops to fully verify the system thoroughly before launch.
Brief video of robotic arm testing
