Space Robotics Systems: The Robotic Arm to Help Astronauts

Abstract

This paper analyses past accomplishments and current space service developments, with a focus on supporting space robotics systems. There is also an effort to predict future space service missions and applications that may help set the course for the advancement of space robotic technologies. The Canadarm will become noticeable through the different concepts laid out and experiences of how it contributed to the space economy. The development and progress of astronauts and robotics will be mixed and different concepts will be shown that bring meaning to the Canadarm. Through the different techniques and dilemmas and visible, The Canadarm has increased the knowledge and exploration of space, has helped astronauts to see deeper into space and have more control of their environment. The Canadarm specializes in many different aspects that contributed to robotic space exploration.

Canadarm: Space Robotics

Established in 1989, the Canadian Space Agency is responsible for coordinating all government-funded space activities in Canada. Some of the more prominent projects of the CSA include robotics, most notably DEXTRE, Canadarm, and Canadarm2. The Canadarm, also known as the Shuttle Remote Manipulator System (SRMS), was a remote controlled mechanical arm and was developed by MacDonald, Dettwiler, and Associates Ltd. (MDA). The robotic arm launched, captured, and repaired satellites, guided astronauts, operated equipment and carried cargo during its 30-year service with NASA's Space Shuttle Program. Throughout space history in the past and present, the Canadarm has contributed to our space economy by it’s specifications and development, the Evolution of Astronauts, and the different robotics it uses to complete the job.

The Canadarm has specific roles and the way it was developed resulted in big impacts in space. One could think of the Canadarm as a human arm with a hand, elbow, and shoulder of 15 meters. A 'joint one-degree-of-freedom' (JOD) was included in each of these three joints. A JOD was a motor-driven gearbox that gave Canadarm more flexibility to move and twist than even a human arm. A TV camera located on the wrist of the robotic arm, as well as an optional camera located on its elbow, operated as the 'eyes' of the Canadarm, while one of the five on-board shuttle computers served as its 'brain.' TV cameras were part of the shuttle's closed-circuit TV system and provided visual indications to an astronaut controlling the robotic arm from within the shuttle. This control station featured hand controllers, display panels, and an input box for signal processing.

The Canadarm weighed 410 kilograms and in the vacuum of Earth could not support itself. As a result, engineers designed a computer-based simulator facility like a video game to evaluate the robotic arm and train astronauts in using it. Before their first flight, the facility, named SIMFAC, confirmed the function of Canadarm. The Canadarm was able to lift more than 30,000 kilograms on Earth or up to 266,000 kilograms in space gravity at rates of up to 60 centimeters per second (depending on the weight). Those payloads could be placed within 5 centimeters of a desired target in any location. The latest aerospace materials, including titanium, stainless steel, and ultra-high-modulus graphite epoxy, were used by engineers to meet the strength requirements. Special attention was required to thermal design and lubrication in the harsh environment.

The arm was completely covered by a multi-layer insulation system composed of alternate layers of golden Kapton, Dacron scrim cloth, and an outer covering of Beta cloth (fiberglass). Critical electronics were protected under extremely cold conditions by thermostatically controlled electric heaters. Canadian industry has largely carried out the $110-million Canadarm development program under the leadership of Canada's National Research Council. CAE Electronics Ltd. and DSMA Atcon Ltd. were part of the industrial team, led by Spar Aerospace Ltd. In February 1981, at Spar's Toronto plant, where it was built, the Canadarm was signed over to NASA. It was integrated into the Columbia space shuttle in June after being carefully trucked to the Kennedy Space Center.

The Canadarm made the space economy and had evolved the astronauts into deeper aspects of space. The first Canadian astronauts were experts in aircraft, which means they were responsible for some shuttle experiments and did not perform duties such as spacewalks. Nevertheless, as the program progressed, NASA invited the Canadians to train as professionals in the mission. The first to undergo this practise was Marc Garneau and Chris Hadfield, who were part of the second Canadian astronaut recruitment in 1992. In the 1990s, Canada set a number of benchmarks for astronauts: first female, first Canadian at Mir Space Station, the first Canadian to run the Canadarm, and the first Canadian to reach the International Space Station. Since then, spacewalks and more complicated activities have been conducted on the space station by Canadian astronauts. It resulted in the station's first Canadian manager, Hadfield, in 2013.

There are currently four astronauts in Canada: Jeremy Hansen and David Saint-Jacques, Joshua Kutryk, and Jennifer Sidey. Saint-Jacques is assigned to Expedition 58/59, due to start in November 2018. Hansen has not yet flown, although media reports said it could be either 2021 or 2022. To Both Kutryk and Sidey are in basic astronaut training and will not be qualified for flights until at least this year, although they will probably not be flying until sometime in the 2020s.

The Canadarm was used to launch and collect spacecraft, like the Hubble Space Telescope, during space shuttle flights. In spacewalks, astronauts also used it to transfer astronauts and supplies. Canadarm was routinely used for space station building exercises after the ISS started operations in 1998. After the 2003 Columbia space shuttle tragedy which killed seven astronauts during re-entry of the spacecraft, the arm was also redesigned. Due to the lack of protective tiles on the shuttle's belly, the cause came in part, Canadarm was used to scan the bottom of each shuttle with a camera soon after it arrived in orbit.

Canadarm's next generation is Canadarm2, the Remote Manipulator System for Space Station (SSRMS), a larger, 'smarter' version of the original. In April 2001, Canadarm2 launched on STS-100. When completely extended, it is 17 meters wide and has seven joints. This played a significant role in constructing the International Space Station and continues on the station to perform maintenance, transfer equipment and supplies, assist space-based astronauts, and manage payloads. It has a Latching End Effector that enables it to be attached to external ports on the outside of the station. The Mobile Base System (MBS) is a work structure which runs over rails that span the space station's distance. It provides the Canadarm2's lateral mobility and was added to the station in June 2002 during STS-111. They are sometimes used in conjunction when both Canadarms were in operation; a procedure in the media called the 'Canadian handshake.'

The MDA also assembled DEXTRE, a robotic hand that has been used for satellite refueling tests since it arrived on the station in 2008. The space station was attached to the Special Purpose Dexterous Manipulator (Dextre) on 16 March 2008. Dextre was built using the same technology as Canadarm and MacDonald, Dettwiler, and Associates were built by the same company. It is basically a handy robot used for a number of tasks outside the orbiting station, including some of the astronauts ' routine tasks during dangerous spacewalks. At the end of Canadarm2 or by the MBS it can be moved around. Dextre has two arms of more than three metres in length, each with seven joints that allow movement in all ways. It has grippers, or 'hands,' which work like the parts of a pocket knife. Each gripper has detectors that give it a human-like sense of touch, and also retractable tools, a camera, lights, and a removable umbilical connector that provides power and data connexions when the robot manipulates electronic equipment or performs experiments.

The 90th and last shuttle mission from Canadarm were to STS-135 on July 2011, carrying the Raffaello MPLM back and forth to the ISS. Discovery's Canadarm is shown in front of her at Udvar-Hazy Center of the National Air and Space Museum. At the Canada Aviation and Space Museum in Ottawa, Canadarm is now on public display. The last Canadarms to fly in space, the SRMS operated aboard Atlantis on the last space shuttle launch, STS-135 in July 2011, being delivered for technology analysis and potential recycling on a future mission to NASA's Johnson Space Center in Houston. The export-oriented commercial gains obtained through the production of the Canadarm include the selling and repair to NASA of four Canadarm systems (one of the five installed was donated); the sale to Japan and Europe of robotic components; the sale of simulators; and the development of robotic equipment for the nuclear industry.

In the high-tech fields of advanced manipulator systems and robotics, the Canadarm identified Canada as a key player. The Canadarm has contributed a lot to our economy and increased the technology of space. The robotic arm deployed spacecraft, caught and fixed them, guided astronauts, working machinery, and transported equipment for NASA's Space Shuttle Program during its 30-year career. In the past and present throughout the history of space, the Canadarm's design and creation, the advancement of astronauts, and the various robotics it uses to complete the job needed to our space economy.