The first Canadarm was sent into space in 1981 when it was attached to NASA’s Endeavor. At 49.2 feet, this fairly small and elegant tool was credited as Canada’s most significant space contribution and is still used today. Yet the drawbacks of Canadarm, its weigh limitations and the fact that it must return with the shuttle after reach voyage, made it worth replicating the robot, on a larger, longer-lasting scale. In the late 1990s, Canada did just this, launching the Canadarm2.
Unlike it’s predecessor, Canadarm2 is bigger, more flexible and never slated to return to earth. At a length of 57.7 feet and weight (on earth of course) of 3,9681 pounds, Canadarm2 is no wimp, boasting weight bearing capacities of upwards of 235,000 pounds. It can flex at 7 joints, unlike Canadarm’s 6: 3 in the shoulder joint, 1 in the elbow and 3 in the wrist. Each of these joints are capable of rotating a full 540 degrees, and the ‘hand’ portion is equipped with touch sensors. The robot is able to move along the entire bottom length of the International Space Station, relying on a Mobile Base System installed in 2002 that it runs along like railway tracks.
Canadarm2 can operate on its own, autonomously, or with human assistance. Designed to be refurbished in space, Canadarm2 is made of 19 compacted layers of thermoplastic, a heat tolerant plastic made of high-strength carbon fibers. Not only does Canadarm2 run experiments and execute special tasks, but it also is crucial to the space station’s refueling process. Since NASAs reduction in funds, private companies have begun contracting out some of these routine, mandatory processes. In light of this, SpaceX (http://www.spacex.com) has been launching ‘dragons’ to ISS when necessary – space shuttles with food, supplies, clothing, additional experiment equipment and even spare-space parts. Roughly three weeks after landing dragon is sent back to earth, plummeting into the Pacific Ocean. There it is collected by scientists ready to process the data and samples loaded by the ISS team before departure.
Canadarm2 is slated to catch another SpaceX ‘dragon’ sometime this year.
Want to see it in action? Watch Chris Hadfield, former ISS staff, play with the arm!