Milestone-Proposal:The Space Shuttle Remote Manipulator System

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Docket #:2015-07

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To the proposer’s knowledge, is this achievement subject to litigation?

Is the achievement you are proposing more than 25 years old? Yes

Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes

Did the achievement provide a meaningful benefit for humanity? Yes

Was it of at least regional importance? Yes

Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes

Has an IEEE Organizational Unit agreed to arrange the dedication ceremony? Yes

Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes

Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes

Year or range of years in which the achievement occurred:


Title of the proposed milestone:

The Shuttle Remote Manipulator System (Canadarm), 1981

Plaque citation summarizing the achievement and its significance:

On 11 April 1981, NASA formally accepted the Shuttle Remote Manipulator System (SRMS) or Canadarm developed by SPAR Aerospace and the National Research Council of Canada. By providing the means to manipulate and transfer heavy payloads, support astronauts on EVA, and conduct inspections and repairs to the Shuttle, the SRMS revolutionized manned spaceflight and played a pivotal role in the Shuttle program.

In what IEEE section(s) does it reside?


IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:

IEEE Organizational Unit(s) paying for milestone plaque(s):

Unit: IEEE Canada
Senior Officer Name: Senior officer name masked to public

IEEE Organizational Unit(s) arranging the dedication ceremony:

Unit: IEEE Canada
Senior Officer Name: Senior officer name masked to public

IEEE section(s) monitoring the plaque(s):

IEEE Section: Toronto Section
IEEE Section Chair name: Section chair name masked to public

Milestone proposer(s):

Proposer name: Proposer's name masked to public
Proposer email: Proposer's email masked to public

Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.

Street address(es) and GPS coordinates of the intended milestone plaque site(s):

9445 Airport Rd, Brampton, ON L6S 4J3

Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.

Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need. The intended site is the home of the Division that developed the Canadarm.

Are the original buildings extant?

The space robotics group started out at 1235 Ormont Drive in Weston Ontario. On the 6th of January 1992, the group relocated to 9445 Airport Road in Brampton, Ontario.

Details of the plaque mounting:

The plaque will be mounted on a stand in the reception area in the vicinity of other awards and mementos that the division has received, including flags that have flown in space, citations from NASA and more recently a Hall of Fame award for our neuroArm project.

How is the site protected/secured, and in what ways is it accessible to the public?

The reception area is the most accessible indoor portion of the facility and is seen by all visitors to the facility. Casual visitors can view the plaque and other awards and mementos without requiring a security badge.

Who is the present owner of the site(s)?

MacDonald Dettwiler & Associates, Canada's leading space engineering firm, has leased the site since they completed acquisition of SPAR Space and Advanced Robotics Division on 10 May 1999.

What is the historical significance of the work (its technological, scientific, or social importance)?

General Background

The Shuttle Remote Manipulator System (SRMS) or Canadarm was a joint venture between the governments of the United States and Canada to supply the NASA Space Shuttle program with a robotic arm for the deployment/retrieval of space hardware from the payload bay of the orbiter. Spar was appointed the prime subcontractor to the National Research Council of Canada, now the Canadian Space Agency, in July of 1975 for the Design Development Testing and Evaluation (DDT&E) of the manipulator arm system which was to be supplied to NASA by the Canadian government. Work began on the program in 1975 and in April 1981 the first SRMS was delivered to NASA at a cost of approximately $108 million to the Canadian government. The first flight of the SRMS was later that year - November 12, 1981. NASA subsequently ordered 4 additional Canadarms, one of which was lost in the Challenger accident.

What obstacles (technical, political, geographic) needed to be overcome?

Technical Description

The SRMS is a robotic arm consisting of a shoulder, elbow and wrist joint separated by an upper and lower arm boom giving it a total of six degrees-of-freedom (shoulder pitch and yaw, elbow pitch and wrist pitch yaw and roll). At a total weight of approximately 431 kg, the Canadarm is capable of manoeuvring payloads of up to 14,515 kg at a rate of .06 m/sec with a maximum contingency operation payload weight of 265,810 kg. Under unloaded conditions the SRMS can achieve a maximum translational rate of 0.6 m/sec. Ironically, the SRMS is incapable of supporting its own weight here on earth and it must be supported by specialized ground handling equipment during its acceptance testing and shipment. Although the SRMS can handle very heavy payloads, movement of the tip is very accurately controlled, allowing precise handling of delicate payloads. The length of the Canadarm is approximately 15 m and a computerized control system can be used to deploy payloads to a positional accuracy of +/- 2.0-in and +/- 1.0-degree of a pre-programmed target zone at the aforementioned rates and load conditions. The SRMS may also be operated manually by the astronauts to the same accuracy with the use of hand controllers and closed circuit televisions (CCTV) mounted on the manipulator arm. The SRMS was designed to have a life of ten years or 100 missions.

Technical Issues

SRMS Control System

The movement of the SRMS is controlled by the space shuttles general-purpose computer (GPC). The hand controllers used by the astronauts tell the computer what the astronauts would like the arm to do. Built in software examines what the astronauts commanded inputs are and calculates which joints to move, what direction to move them in, how fast to move them and what angle to move to. As the computer issues the commands to each of the joints it also looks at what is happening to each joint every 80 milliseconds. Any changes inputted by the astronauts to the initial trajectory commanded are re-examined and recalculated by the GPC and updated commands are then sent out to each of the joints. The SRMS control system is continuously monitoring its “health” every 80 milliseconds and should a failure occur the GPC will automatically apply the brakes to all joints and notify the astronaut of a failure condition. The control system also provides a continuous display of joint rates and speeds, which are displayed on monitors located on the flight deck in the orbiter. As with any control system, the GPC can be over-rided and the joints can be operated individually from the flight deck by the astronaut.

End Effector

The End Effector or mechanical hand of the SRMS allows the arm to capture stationary or free flying payloads by providing a large capture envelope (a cylinder 20.3 cm in diameter by 10 cm deep) and a mechanism/structure capable of soft docking and rigidizing. This action is accomplished by a two stage mechanism in the End Effector which closes three cables (like a snare) around a grapple probe (knobbed pin) bolted onto the payload and then draws it into the device until close contact is established and a load of approximately 499 kg is imparted to the grapple probe. The forces developed by the End Effector on the payload through the grapple probe will allow for manoeuvring of the payload without separation from the remainder of the SRMS to the positional accuracy’s previously stated.

What features set this work apart from similar achievements?

Supporting texts and citations to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or chapters in scholarly books. 'Scholarly' is defined as peer-reviewed, with references, and published. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article. All supporting materials must be in English, or accompanied by an English translation.

Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to Please see the Milestone Program Guidelines for more information.

Please email a jpeg or PDF a letter in English, or with English translation, from the site owner(s) giving permission to place IEEE milestone plaque on the property, and a letter (or forwarded email) from the appropriate Section Chair supporting the Milestone application to with the subject line "Attention: Milestone Administrator." Note that there are multiple texts of the letter depending on whether an IEEE organizational unit other than the section will be paying for the plaque(s).