Dominating Robotics in Space – The Canadarm

Part 1 - What does Robotic Space Technology Entail?

Robotics is an important field in space technology and exploration for many reasons: robots can perform tasks that may be too dangerous for humans, they can perform tasks at a faster pace and the result of the task once finished, is generally done to a better standard (Wilcox, Ambrose, & Kumar, 2018). Space robots are also important because they can undergo missions without the need of human presence such as exploration, assembly, construction, and maintenance (Wilcox et al., 2018). Due to the fact that there is no human presence required, there is a decrease in limitations on things like exploration – for example; the Mars rover. No human has been to Mars; however, scientists have been able to study data from samples collected by rovers and thus decreasing the limitations on what we can and cannot explore. For Canada, one of, if not their greatest accomplishment in space robotics is the Canadarm. The Canadarm technology has been on board the ISS for almost 40 years. The original Canadarm - sent to the ISS in November of 1981 – was designed to provide services to the global partners at the ISS, such as; catching satellites for repair, attaching to capsules and cargo for transport, transporting astronauts around the outside of the station and much more (Doetsch, 2013). At 15 meters long, the Canadarm proves to be a very useful tool for the astronauts in the construction of the ISS in the 1980’s and 1990’s.

There were three companies involved in the manufacturing of the Canadarm: CAE Electronics Ltd., DSMA Atcon Ltd, and Spar Aerospace Ltd. – who was the head of the development. However, in 1999, Spar Aerospace’s division of space robotics had been bought out by MacDonald, Dettwiler and Associates Ltd. (Doetsch, 2013).

Part 2 - The Canadarms

• The Canadarm (1981-2011)

The Canadarm was 15 meters long with six joints – two in the shoulder, one in the elbow and three in the wrist. These joints allowed for flexibility and movement not even a human arm could possess (Doetsch, 2013). At roughly 905lbs, the Canadarm was designed to be more functional and vastly larger than a human’s arm. This was to allow these astronauts to do what they normally could never do. In Earth’s gravity the arm could not hold itself up, however in low earth orbit, the Canadarm could place an object five centimeters from its target. With some alterations, the Canadarm was able to put a peg through a hole at 50 feet, within 60/1000 of an inch in clearance (Dean, 2006). Former National Aeronautics and Space Administration (NASA) astronaut Joe Engle – who was the commander of the mission that first flew the Canadarm to the ISS – is on record of saying, “It was like an extension of your own arm, … I was just enamored with how neat it was, how much like the human arm it was. How intuitive it was to use the arm. It was my first exposure to real robotics.” (Dean, 2006). No one had ever designed, manufactured or even used technology like this given the magnitude of its size and precision. What made the Canadarm such a technological breakthrough was how it was controlled. A joystick was used to aim the tip of the arm – also known as the ‘Canada Hand’ – and the joints would work in tandem to align the Canada Hand to the desired target (Dean, 2006). All you had to do was tell the robot where you wanted the Canada Hand to go.

Some eventful moments in Canadarm’s long and historical career include repairing and deploying the Hubble Space Telescope on numerous occasions, docking NASA space shuttles to the Russian Mir space station during the ISS’ construction and knocking off ice formations that were blocking off a space shuttle’s waste exit. The Canadarm was able to dislodge the ice formations by lightly striking them with the Canadarm. In 1985, a satellite that was on its way to the ISS from a different orbit, got stuck in that orbit when the rockets did not fire. Houston thought the problem was that the switch did not trip after being unloaded from the space shuttle’s cargo bay. The Canadarm was able to reach out and physically trip the switch, however, unfortunately that did not solve the problem. Nearly a month later, the Canadarm grabbed hold of the satellite from around 15 meters away in order to solve the problem, amongst many others in its career, for repairs (Dean, 2006).

• Canadarm2 (2001-present)

After 98 Space Transportation System (STS) missions the original Canadarm was sent to low earth orbit, STS-100 brought the new and improved Canadarm2 to the ISS in April of 2001. Some major differences of Canadarm and Canadarm2, are that Canadarm2 is 17 meters long, has a carrying capacity of approximately 225,800lbs and has seven joints instead of six (Canadian Space Agency [CSA], 2018). The capturing mechanism on the Canadarm2 is also different from the original. The arm features two hands known the Latching End Effectors (LEE), this design allows for two possible anchor points - one to the ISS and one to the desired target (CSA, 2018). However, despite their structural and capability differences, the two Canadarms work, at times, in tandem. This operational maneuver was coined in the media as ‘The Canadian Handshake’. This maneuver occurs when a vehicle, piece of machinery, part of the space station or even an astronaut needs to be transported from far distances along the outside of the ISS. Power Data Grapple Fixtures (PDGF) are built into the outer walls if the ISS. These PDGFs are the way in which the Canadarm2 gets around the space station. At least one of the anchor points must be attached for the arm to operate – moving across the space station similar to the way a slinky moves down a set of stairs (CSA, 2018). Another interesting fact about the Canadarm program, is the impact it has on the research and development for technology on Earth. For example, the research that went into developing the Canadarms also went into aiding developers in designing the neuroArm. The neuroArm was the world’s first robots able to perform brain surgery in an MRI machine (CSA, 2018). The installation of the of the Canadarm2 was also historic. Chris Hadfield, while installing the Canadarm2, would be the first Canadian astronaut to perform a spacewalk. Hadfield and NASA astronaut Scott Parazynski underwent vigorous training exercises to prepare them for the unpacking and installation of the arm once in space. From installation training in 40 foot deep swimming pools in full gear to long virtual training sessions, Hadfield and Parazynski had to be well prepared going into the mission. The mission was successful, Hadfield and Parazynski had unbolted the arm from its pallet, manually unfolded the 17 meter long arm and attached the hinges that allowed the two booms to move at the elbow joint (CSA, 2018). Canadarm2 to this day remains on the ISS and continues to help astronauts aboard the ISS in operation maneuvers outside of the space station.

• Canadarm3 (Under-Development, TBA)

NASA is in the middle of developing their Lunar program, its purpose is to provide easier and sustainable access to the moon for astronauts so that they can conduct science experiments and research studies. NASA is currently designing a Lunar space station called Gateway. Gateway is similar to the ISS, global partners will be allowed to use it, however it will be in the orbit of the Moon and not Earth (Canadian Space Agency [CSA], 2020). Canada is working alongside NASA and others, in designing the architecture of the Lunar space station. Because like the ISS, Gateway will need a robotic arm to aid astronauts in operations similar to what Canadarm and Canadarm2 do for the ISS. However, Canadarm3 is a lot different – this is mostly to do with the differences in the station in which the arms will be attached to. Canadarm3 will consist of two arms that are designed to work as one: An eight and-a-half meter long arm, a smaller more dexterous arm and a set of detachable tools (CSA, 2020). Something else that is ground breaking about the Canadarm3 is that it is to work 100% autonomously, however there our manual overrides at CSA headquarters in Longueuil, Quebec and on Gateway itself. This autonomous feature is ground breaking because Canadarm3 will be able to automatically detect an issue with the bigger arm and fix it with the smaller one if necessary, essentially making it able to maintain itself in space (CSA, 2020). This is important because the ISS is in low Earth orbit, and spare parts are able to get to the ISS from Earth a lot quicker. Gateway is orbiting the Moon; therefore, it is advantageous to have mechanisms and technology that can repair and maintain itself for maximum efficiency. Another aspect of all the Canadarms’ is that they are able to perform exploratory missions of the space station and vehicles: Checking for damages, investigating issues and getting better angles of astronauts during spacewalks. Very similar to what is now the neuroArm. When the Canadarm3 will be operational is dependent on the manufacturing and development of Gateway. When Gateway is ready to be launched to the Moon, Canadarm3 will be ready as well.

Canada is one of the leaders in space robot technology and the services that Canadarm and Canadarm2 have provided to the ISS and the global partners on aboard is invaluable. This November will mark 39 continuous years of the Canadarm program’s presence on the ISS. The Canadarm – like a lot of great inventions in history – proved to be far more valuable than initially thought. These past 39 years have solidified Canada’s reputation in the field on the global scale. Now with the upcoming Gateway project, the Canadian Space Agency (CSA) have incorporated themselves in the future of space technology and exploration and will only grow their legacy in space.