Canadian Space Agency testing satellite-saving robot arms
Engineers are usually struggling to make robots as dexterous as humans in a given situation, but in space the situation is reversed. The squishy human frame requires heavy duty protection to survive even short periods in the unforgiving vacuum of space. A robot arm, however, can easily be more versatile in space than a human with clumsy spacesuit hands. The Canadian Space Agency (CSA) has been making the Canadarm robot arms for decades, and the newest versions are in testing right now. Their main function? Saving satellites.
The Canadarm2 currently serves as the main grasper on the hull of the International Space Station (ISS). It is used mostly to move payloads around and guide objects to the docking port. When SpaceX’s Dragon capsule started making runs to the ISS, it was the Canadarm2 that grabbed it from orbit and brought it to the airlock. This was seen as considerably more safe than having a robotic pod maneuver itself up to the fragile skin of the ISS.
The new Canadarms, dubbed Next Generation Canadarm (NGC), comes in two sizes: a huge 15 meter arm, and a more compact 2.58 meter one. Both have six degrees of freedom for extreme flexibility. The large arm is close in size to the Canadarm2 currently in service on the ISS, but it’s considerably lighter. Both NGC arms have telescoping segments that extend out to those lengths, but can also be retracted when not in use. This has the practical upshot of making them much more compact. In fact, the 15-meter arm can shrink down to only take up five meters of cubic space. That’s about the same as a minivan, which is just enough to fit on-board future spacecraft designs.
The smaller NGC is based not on the Canadarm2, but on Dextre. The Dextre is a smaller arm mounted to the Canadarm2. It’s main task is performing delicate repair work like changing batteries and replacing cameras. The small NGC is being designed for similarly careful tasks, but satellite repair, upgrade, and refueling is the main focus.
There is already an abundance of space junk in orbit of our planet. This moving debris is a serious danger to both manned and unmanned missions. The small arm will have an array of sophisticated tools to make repairs to satellites so they might remain operational for longer. Just like the Canadarm2 and Dextre, the NGC arms are designed to be attached to each other. The large arm will be doing the heavy lifting, but the small one can be ready to step in for any sensitive work. The small NGC could also be mounted by itself if the large arm isn’t needed for docking operations.
Before anyone gets to knock around real (expensive) satellites in orbit, the entire rig is being thoroughly tested here on Earth in a simulator. The testbed allows operators to guide dummy satellites together for docking using the arms in both full manual and semi-autonomous mode.
The NGC arms will presumably get snappier names when they are ready for service, but no one is saying when that will be yet. One thing we do know, Chris Hadfield is not the only claim to fame Canada’s space program has (though he is pretty cool).
