View source for Canadarm

{{Short description|Robotic arm used on Space Shuttles}}
{{about|the robotic arm on the [[Space Shuttle]]|the robotic arm on the [[International Space Station]]|Mobile Servicing System}}
{{Use Canadian English|date=June 2020}}
{{Use dmy dates|date=May 2020}}
{{Infobox spacecraft instrument
| Name = Shuttle Remote Manipulator System
| Image = Canadarm 1 - STS-72.jpg
| Caption = Canadarm (right) during Space Shuttle mission [[STS-72]]
| Operator = [[NASA]]
| Manufacturer = [[Spar Aerospace]]
| Type = [[robotic arm]]
| Webpage = {{URL|http://www.asc-csa.gc.ca/eng/canadarm/default.asp}}
| Mass = {{Unbulleted list
  | '''Arm:''' {{cvt|410|kg}}
  | '''Total:''' {{cvt|450|kg}} 
}}
| Dimensions = {{cvt|1520|x|38|cm}}
| Number = 5
| Spacecraft = [[Space Shuttle]]
| SC_Operator = [[NASA]]
| Launch_Site = [[Kennedy Space Center|Kennedy]] [[LC-39]]
}}

'''Canadarm''' or '''Canadarm1''' (officially '''Shuttle Remote Manipulator System''' or '''SRMS''', also '''SSRMS''') is a series of [[robotic arm]]s that were used on the [[Space Shuttle]] orbiters to deploy, manoeuvre, and capture [[payload]]s. After the [[Space Shuttle Columbia disaster|Space Shuttle ''Columbia'' disaster]], the Canadarm was always paired with the [[Orbiter Boom Sensor System]] (OBSS), which was used to inspect the exterior of the shuttle for damage to the [[Space Shuttle thermal protection system|thermal protection system]].

== Development ==
[[File:Life Size replica of the Canadarm.jpg|thumb|Life-size replica of the Canadarm at the Euro Space Center in Belgium]]

In 1969, [[Canada]] was invited by the [[NASA|National Aeronautics and Space Administration]] (NASA) to participate in the [[Space Shuttle program]].<ref name="25Years">{{cite book |url=https://books.google.com/books?id=YzVPAAAAMAAJ|title=A Heritage of Excellence: 25 years at Spar Aerospace Limited|last=Dotto|first=Lydia|date=1992|publisher=Spar Aerospace Limited|others=David Steel |isbn=0-9696618-0-0|location=Canada|pages=41–42|quote=[Frank] Mee is the inventor of the Canadarm hand, technically known as the "end effector.}}</ref> At the time what that participation would entail had not yet been decided but a manipulator system was identified as an important component.<ref name=25Years/> Canadian company [[Dilworth Secord and Meagher|DSMA]] ATCON had developed a robot to load fuel into [[CANDU reactor|CANDU nuclear reactors]]; this robot attracted NASA's attention.<ref name=25Years/> In 1975, NASA and the [[National Research Council (Canada)|Canadian National Research Council]] (NRC) signed a memorandum of understanding that Canada would develop and construct the Canadarm.<ref>{{cite book|url=https://books.google.com/books?id=CqI6waJAUnEC|title=Browsing Science Research at the Federal Level in Canada: History, Research Activities and Publications|last=Wilks|first=Brian|date=2004|publisher=University of Toronto Press|pages=117|isbn=9780802088116|access-date=22 November 2013}}</ref>

NRC awarded the manipulator contract to [[Spar Aerospace]] (now [[MDA (company)|MDA]]).<ref name="UofAEngMag"/> Three systems were constructed within this design, development, test, and evaluation contract: an engineering model to assist in the design and testing of the Canadarm, a qualification model that was subjected to environmental testing to qualify the design for use in space, and a flight unit.

===End effector===
Anthony "Tony" Zubrzycki, a design engineer at DSMA ATCON,<ref name=":0">{{Cite book|title=Make The Wind Blow|last=Melbourne|first=James V.|publisher=Heirloom Publishing Inc.|year=2001|isbn=0-9694247-8-7|pages=62–77}}</ref> while seconded to SPAR, originated the concept for the Canadarm End Effector, inspired by an elastic band around his fingers.<ref name=":0"/> Zubrzycki formally presented this concept to NASA officials.<ref name=":0"/> Frank Mee, head of the SPAR mechanical development laboratory, built the end effector prototype<!--At his home, he fabricated a small model made out of cardboard and string; and brought it to work.<ref name=25Years/>--> based on Tony's concept and is credited by SPAR<ref name=":0"/> as the inventor of the Canadarm End Effector. The three-wire crossover design won over the claw-like mechanisms and others, such as the camera iris model,<ref name=":0"/> that were being considered.

===Controls and software=== 
The main control algorithms were developed by SPAR and by subcontractor [[Dynacon Inc.]] of [[Toronto]]. [[CAE Inc.|CAE Electronics Ltd.]] in [[Montreal]] provided the display and control panel and the hand controllers located in the Shuttle aft flight deck. Other electronic interfaces, servo amplifiers, and power conditioners located on the Canadarm were designed and built by SPAR at its Montreal factory. The graphite composite boom that provides the structural connection between the shoulder and the elbow joint and the similar boom that connects the elbow to the wrist were produced by [[General Dynamics]] in the [[United States]]. Dilworth, Secord, Meagher and Associates, Ltd. in Toronto was contracted to produce the engineering model end effector then SPAR evolved the design and produced the qualification and flight units. The Space Shuttle flight software that monitors and controls the Canadarm was developed in [[Houston, Texas]], by the Federal Systems Division of [[IBM]]. [[Rockwell International]]'s Space Transportation Systems Division designed, developed, tested, and built the systems used to attach the Canadarm to the payload bay of the orbiter.

An acceptance ceremony for NASA was held at Spar's RMS Division in Toronto on 11 February 1981.<ref name=25Years/> Here [[Larkin Kerwin]], then the head of the NRC, gave the SRMS the informal name, Canadarm.  The term was originally coined by Dr. Wally Cherwinski for use by Larkin Kerwin during his speech at the press conference.<ref name=25Years/> The NRC Canadarm Project Manager, Dr. Art Hunter, worked with colleagues, NASA and Spar, to add the Canadian flag and wordmark onto the arm to fly Canadian colours with those of the USA.

The first Canadarm was delivered to NASA in April 1981.<ref>{{cite web|url=http://www.ieee.ca/millennium/canadarm/canadarm_technical.html|title=The Shuttle Remote Manipulator System – The Canadarm |publisher=IEEE Canada|access-date=22 November 2013}}</ref> Astronaut [[Judith Resnik]] developed the NASA [[software]] and onboard operating procedures for the system.<ref>''Engineering Women: Re-visioning Women's Scientific Achievements and Impacts'', By Jill S. Tietjen, Springer 2016, page 72</ref> In all, five arms – Nos. 201, 202, 301, 302, and 303 – were built and delivered to NASA. Arm 302 was lost in the ''Challenger'' accident.<ref name="canadarm">{{cite web|url=http://www.asc-csa.gc.ca/eng/canadarm/flight.asp|publisher=Canada Space Agency|title=Flight History of Canadarm|date=28 October 2011
|access-date=27 October 2012}}</ref>

== Design and capabilities ==
[[File:Hubble First Servicing EVA - GPN-2000-001085.jpg|left|thumb|[[Story Musgrave]], anchored on the end of the Canadarm, prepares to be elevated to the top of the Hubble Space Telescope during [[STS-61]].]]

The original Canadarm was capable of deploying payloads [[mass|weighing]] up to {{convert|65,000|lb}} in space.<ref>{{cite web |last1=Demeo |first1=M.E. |title=REMOTE MANIPULATOR SYSTEM (RMS)- BASED CONTROLS-STRUCTURES INTERACTION(CSI) FLIGHT EXPERIMENT FEASIBILITY STUDY |date=January 1990 |url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900007820.pdf}}</ref> In the mid-1990s, the arm control system was redesigned to increase the payload capability to {{convert|586,000|lb}} in order to support space station assembly operations.<ref>{{cite web |title=Space Shuttle Canadarm Robotic Arm Marks 25 Years in Space |url=https://www.nasa.gov/mission_pages/shuttle/behindscenes/rms_anniversary.html |access-date=26 June 2020 |archive-date=25 February 2023 |archive-url=https://web.archive.org/web/20230225184958/https://www.nasa.gov/mission_pages/shuttle/behindscenes/rms_anniversary.html |url-status=dead }}</ref> While able to maneuver payloads with the mass of a loaded bus in space, the arm motors cannot lift the arm's own weight when on the ground.<ref name="UofAEngMag"/> NASA, therefore, developed a model of the arm for use at its training facility within the [[Johnson Space Center]] located in [[Houston, Texas]]. The Canadarm can also retrieve, repair and deploy satellites, provide a mobile extension ladder for [[extravehicular activity]] crew members for work stations or foot restraints, and be used as an inspection aid to allow the flight crew members to view the orbiter's or payload's surfaces through a television camera on the Canadarm.

The basic Canadarm configuration consists of a manipulator arm, a Canadarm display, and a control panel, including rotational and translational hand controllers at the orbiter aft flight deck flight crew station, and a manipulator controller interface unit that interfaces with the orbiter computer. One crew member operates the Canadarm from the aft flight deck control station, and a second crew member usually assists with television camera operations. This allows the Canadarm operator to view Canadarm operations through the aft flight deck payload and overhead windows and through the closed-circuit television monitors at the aft flight deck station.

The Canadarm is outfitted with an explosive-based mechanism to allow the arm to be jettisoned. This safety system would have allowed the Orbiter's payload bay doors to be closed in the event that the arm failed in an extended position and was not able to be retracted.<ref name=UofAEngMag>{{cite news|author=Garry Lindberg|title=Canadarm and its U of A Connections |url=http://www.uofaweb.ualberta.ca/uofaengineer/article.cfm?article=28369&issue=28299|work=U of A Engineer Magazine|publisher=University of Alberta|access-date=7 December 2011|url-status=dead |archive-url=https://web.archive.org/web/20041129001731/http://www.uofaweb.ualberta.ca/uofaengineer/article.cfm?article=28369&issue=28299|archive-date=29 November 2004}}</ref>

The Canadarm is {{convert|15.2|m}} long and {{convert|38|cm}} diameter with six [[Degrees of freedom (mechanics)|degrees of freedom]]. It weighs {{convert|410|kg}} by itself, and {{convert|450|kg}} as part of the total system. The Canadarm has six joints that correspond roughly to the joints of the human arm, with shoulder yaw and pitch joints, an elbow pitch joint, and wrist pitch, yaw, and roll joints.<ref name=CSA-structure/> The [[Robot end effector|end effector]] is the unit at the end of the wrist that grapples the payload's [[grapple fixture]]. The two lightweight boom segments are called the upper and lower arms. The upper boom connects the shoulder and elbow joints, and the lower boom connects the elbow and wrist joints.<ref name=sts-caws>{{Cite web |url=http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-caws.html#sts-deploy |title=''RMS: PAYLOAD DEPLOYMENT AND RETRIEVAL SYSTEM'' |access-date=20 February 2007 |archive-date=31 December 2016 |archive-url=https://web.archive.org/web/20161231022452/http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-caws.html#sts-deploy |url-status=dead }}</ref><ref name=CSA-structure>{{Cite web |url=https://www.asc-csa.gc.ca/eng/canadarm/description.asp |title=''The structure of Canadarm'' |access-date=19 May 2020 |archive-date=10 June 2020 |archive-url=https://web.archive.org/web/20200610214422/https://www.asc-csa.gc.ca/eng/canadarm/description.asp |url-status=dead }}</ref>

== Service history ==
[[File:STS057-89-067 - Wisoff on the Arm (Retouched).jpg|thumb|[[Peter Wisoff|Peter J.K. Wisoff]] on the end of the arm, 1993]]
[[File:STS-116 - P5 Truss hand-off to ISS (NASA S116-E-05765).jpg|thumb|315px|right|The Canadarm2 moves toward a P5 truss section, being held by ''Discovery''{{'}}s Canadarm, in preparation for a hand-off during [[STS-116]].]]

A simulated Canadarm installed on the {{OV|101}} was seen when the prototype orbiter's payload bay doors were open to test hangar facilities early in the Space Shuttle program.<ref>{{cite news|first=Justin |last=Ray|url=http://spaceflightnow.com/delta/d352/omcf/|title=Vandenberg's space shuttle hangar|date=5 January 2011|work=Spaceflight Now|access-date=27 October 2012}}</ref> The Canadarm was first tested in orbit in 1981, on {{OV|102}}'s [[STS-2]] mission. Its first operational use was on [[STS-3]] to deploy and manoeuvre the Plasma Diagnostics Package.<ref name="canadarm"/> Canadarm subsequently flew on more than 90 missions with all five orbiters.

Since the installation of the [[Mobile Servicing System|Canadarm2]] on the [[International Space Station]] (ISS), the two arms have been used to hand over segments of the station for assembly from the orbiter's Canadarm to the Canadarm2; the use of both elements in tandem has earned the nickname of "Canadian Handshake" in the media.<ref>{{cite web |title=Coming to space: A Canadarm handshake? |url=https://www.cbc.ca/news/science/coming-to-space-a-canadarm-handshake-1.573426 |website=CBC News |access-date=27 January 2024 |date=11 Aug 2006}}</ref>

=== Retirement ===
The Canadarm's 90th and final Shuttle mission was in July 2011 on [[STS-135]], delivering the [[Raffaello MPLM|''Raffaello'']] [[Multi-Purpose Logistics Module|MPLM]] to the ISS and back. It is on display with ''Atlantis'' at the [[Kennedy Space Center Visitor Complex]]. ''Discovery'''s Canadarm is displayed next to it in the [[Steven F. Udvar-Hazy Center|National Air and Space Museum's Udvar-Hazy Center]].<ref name=chrisg>{{cite news|author=Chris Gebhardt|url=http://www.nasaspaceflight.com/2010/11/discoverys-retirement-provide-insight-fate-fleets-robotic-arms/|title=Discovery's retirement plans provide insight into the fate of the robotic arm|date=17 November 2010|publisher=NASASpaceflight|access-date=27 October 2012}}</ref> ''Endeavour'' left its OBSS at the International Space Station as part of its [[STS-134|final mission]], while its Canadarm was originally going to be displayed in the headquarters of the [[Canadian Space Agency]] (CSA).<ref name=chrisg/> However, ''Endeavour''{{'}}s Canadarm is now on permanent display at the [[Canada Aviation and Space Museum]] in [[Ottawa]].<ref>{{cite news|author=Andy Johnson|url=https://www.ctvnews.ca/sci-tech/article/unveiling-exhibit-hadfield-sends-first-canadarm-last-command-from-space/|title=Unveiling exhibit, Hadfield sends first Canadarm 'last command' from space|date=2 May 2013|work=CTV News|access-date=2 May 2013}}</ref><ref>{{cite news|author=Elizabeth Howell|url=http://www.space.com/20949-space-shuttle-canadarm-museum-exhibit.html|title=Space Shuttle's Robotic Arm Goes on Display at Canadian Museum|date=2 May 2013|work=Space.com|access-date=2 May 2013}}</ref><ref>{{cite news|author=Canadian Space Agency|url=http://www.asc-csa.gc.ca/eng/media/news_releases/2013/0502.asp|title=Minister Moore Unveils Exhibit for Canada's National Space Icon: the Canadarm|date=2 May 2013|work=Canadian Space Agency|access-date=1 July 2013|url-status=dead|archive-url=https://web.archive.org/web/20130506062113/http://www.asc-csa.gc.ca/eng/media/news_releases/2013/0502.asp|archive-date=6 May 2013}}</ref> The last of the Canadarms to fly in space, the SRMS flown aboard ''Atlantis'' on STS-135 in July 2011, was shipped to NASA's Johnson Space Center in Houston for engineering study and possible reuse on a future mission.<ref>{{cite news| url=http://www.collectspace.com/news/news-050213a.html|title=Canadarm on display: Space shuttle robot arm unveiled at Canadian museum|date=2 May 2013}}</ref>

== Derivatives ==

=== Canadarm2 ===
{{main|Canadarm2}}
Based on the Canadarm1, the larger [[Mobile Servicing System#Canadarm2|Canadarm2]] is used for berthing the trusses, berthing the commercial vehicles, and inspecting the whole [[International Space Station]].

=== Canadarm3 ===
{{main|Canadarm3}}
The smaller Canadarm3 will be used for berthing the modules and inspecting the [[Lunar Gateway]].<ref>{{cite news|last1=Semeniuk|first1=Ivan|title=Canada's space program sets new course with historic commitment to lunar outpost|url=https://www.theglobeandmail.com/canada/article-canada-is-going-to-the-moon-trudeau-announces-canada-will-join-the/|access-date=3 March 2019|work=[[The Globe and Mail]]|date=28 February 2019|location=Toronto}}</ref> In June 2024, the full contract for design and construction of the arm was awarded to [[MDA (company)|MDA Space]].<ref>{{Cite web |last=Agency |first=Canadian Space |date=2024-06-27 |title=Canada begins detailed design, construction and testing of Canadarm3 for Gateway |url=https://www.canada.ca/en/space-agency/news/2024/06/canada-begins-detailed-design-construction-and-testing-of-canadarm3-for-gateway.html |access-date=2024-06-29 |website=www.canada.ca}}</ref>

== In popular media ==
* On November 13, 2012, Google Canada displayed a [[Google doodle|doodle]] on its home search page to celebrate the 31st anniversary of the Canadarm's first use in space.<ref name=googdood>{{cite news
|url=https://www.cbc.ca/news/science/google-doodle-honours-canadarm-at-31-1.1154285|title=Google doodle honours Canadarm at 31|date=13 November 2012|work=CBC News|access-date=13 November 2012}}</ref>
* Starting November 7, 2013, Canadarm2 was included on the back of the [[Canadian five-dollar note|Canadian five dollar note]].

== See also ==
{{Portal|Spaceflight}}
* [[List of Canadian inventions and discoveries]]
* {{Annotated link|Dextre}}
* {{Annotated link|European Robotic Arm}}
* {{Section link|Kibo (ISS module)#Remote Manipulator System}}
* {{Annotated link|Mobile Servicing System}}
* {{Annotated link|Strela (crane)|Strela}}

==References==
{{Reflist|30em}}

== External links ==
{{Commons category|Canadarm}}
* [http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-caws.html#sts-deploy NASA:''RMS: PAYLOAD DEPLOYMENT AND RETRIEVAL SYSTEM''] {{Webarchive|url=https://web.archive.org/web/20161231022452/http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts-caws.html#sts-deploy |date=31 December 2016 }}
* [http://www.asc-csa.gc.ca/eng/canadarm/default.asp Canadian Space Agency : Canadarm]
* [http://www.cbc.ca/archives/categories/science-technology/technology/canadarm-a-technology-star/topic-canadarm---a-technology-star.html CBC Digital Archives - Canadarm - A Technology Star]
{{MDA Space Missions|state=autocollapse}}
{{Canadian Space Agency}}
{{Space Shuttle}}

[[Category:Spacecraft components]]
[[Category:Space program of Canada]]
[[Category:Science and technology in Canada]]
[[Category:Space Shuttle program]]
[[Category:Space robots]]
[[Category:Robotic manipulators]]
[[Category:1981 robots]]