Canadarm or Canadarm1 (officially Shuttle Remote Manipulator System or SRMS, also SSRMS) is a series of
robotic arm
A robotic arm is a type of mechanical arm, usually programmable, with similar functions to a human arm; the arm may be the sum total of the mechanism or may be part of a more complex robot. The links of such a manipulator are connected by joints ...
s that were used on the
Space Shuttle
The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program na ...
orbiters to deploy, manoeuvre, and capture
payload
Payload is the object or the entity which is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of ...
s. After the
Space Shuttle ''Columbia'' disaster, the Canadarm was always paired with the
Orbiter Boom Sensor System
The Orbiter Boom Sensor System (OBSS) was a 50-foot (15.24 m) boom carried on board NASA's Space Shuttles. The boom was grappled by the Canadarm and served as an extension of the arm, doubling its length to a combined total of 100 feet (30 m). At ...
(OBSS), which was used to inspect the exterior of the shuttle for damage to the
thermal protection system
Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the entr ...
.
Development
![Life Size replica of the Canadarm](https://upload.wikimedia.org/wikipedia/commons/7/78/Life_Size_replica_of_the_Canadarm.jpg)
In 1969,
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
was invited by the
National Aeronautics and Space Administration
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding th ...
(NASA) to participate in the
Space Shuttle program
The Space Shuttle program was the fourth human spaceflight program carried out by the U.S. National Aeronautics and Space Administration (NASA), which accomplished routine transportation for Earth-to-orbit crew and cargo from 1981 to 2011. Its ...
.
At the time what that participation would entail had not yet been decided but a manipulator system was identified as an important component.
[ Canadian company DSMA ATCON had developed a robot to load fuel into CANDU nuclear reactors; this robot attracted NASA's attention.][ In 1975, NASA and the Canadian National Research Council (NRC) signed a memorandum of understanding that Canada would develop and construct the Canadarm.
NRC awarded the manipulator contract to ]Spar Aerospace
SPAR Aerospace was a Canadian aerospace company. It produced equipment for the Canadian Space Agency to be used in cooperation with NASA's Space Shuttle program, most notably the Canadarm, a remote manipulator system.
The company went through a ...
(now MDA
MDA, mda, or ''variation'', may refer to:
Places
* Moldova, a country in Europe with the ISO 3166-1 country code MDA Politics
* Meghalaya Democratic Alliance (2018), ruling coalition government in the Indian State of Meghalaya led by National Pe ...
). 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, while seconded to SPAR, originated the concept for the Canadarm End Effector, inspired by an elastic band around his fingers. Zubrzycki formally presented this concept to NASA officials. Frank Mee, head of the SPAR mechanical development laboratory, built the end effector prototype based on Tony's concept and is credited by SPAR 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, that were being considered.
Controls and software
The main controls algorithms were developed by SPAR and by subcontractor Dynacon Inc. of Toronto
Toronto ( ; or ) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the ancho ...
. CAE Electronics Ltd. in Montreal
Montreal ( ; officially Montréal, ) is the List of the largest municipalities in Canada by population, second-most populous city in Canada and List of towns in Quebec, most populous city in the Provinces and territories of Canada, Canadian ...
provided the display and control panel and the hand controllers located in the Shuttle aft flight deck. Other electronic interfaces, servoamplifiers 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
General Dynamics Corporation (GD) is an American publicly traded, aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth-largest defense contractor in the world by arms sales, and 5th largest in the Uni ...
in the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
. 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
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in ...
, Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
, by the Federal Systems Division of IBM. Rockwell International
Rockwell International was a major American manufacturing conglomerate involved in aircraft, the space industry, defense and commercial electronics, components in the automotive industry, printing presses, avionics and industrial products. R ...
'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.[ Here ]Larkin Kerwin
John Larkin Kerwin (June 22, 1924 – May 1, 2004) was a Canadian physicist.
Born in Quebec City, he studied physics at St. Francis Xavier University and obtained his master's degree in physics at the Massachusetts Institute of Technology. H ...
, then the head of the NRC, gave the SRMS the informal name, Canadarm.[
The first Canadarm was delivered to NASA in April 1981. Astronaut ]Judith Resnik
Judith Arlene Resnik (April 5, 1949 – January 28, 1986) was an American electrical engineer, software engineer, biomedical engineer, pilot and NASA astronaut who died in the Space Shuttle ''Challenger'' disaster. She was the fourth woman, ...
developed the NASA software
Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work.
At the lowest programming level, executable code consists ...
and onboard operating procedures for the system. 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.
Design and capabilities
The original Canadarm was capable of deploying payloads weighing
In science and engineering, the weight of an object is the force acting on the object due to gravity.
Some standard textbooks define weight as a vector quantity, the gravitational force acting on the object. Others define weight as a scalar quan ...
up to in space. In the mid-1990s, the arm control system was redesigned to increase the payload capability to in order to support space station assembly operations. While able to manoeuvre payloads with the mass of a loaded bus in space, the arm motors cannot lift the arm's own weight when on the ground. NASA therefore developed a model of the arm for use at its training facility within the Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
located in Houston
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in ...
, Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
. The Canadarm can also retrieve, repair and deploy satellites, provide a mobile extension ladder for extravehicular activity
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA in ...
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 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.
The Canadarm is long and diameter with six degrees of freedom
Degrees of freedom (often abbreviated df or DOF) refers to the number of independent variables or parameters of a thermodynamic system. In various scientific fields, the word "freedom" is used to describe the limits to which physical movement or ...
. It weighs by itself, and 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.[ The ]end effector
In robotics, an end effector is the device at the end of a robotic arm, designed to interact with the environment. The exact nature of this device depends on the application of the robot.
In the strict definition, which originates from serial ro ...
is the unit at the end of the wrist that grapples the payload's grapple fixture
Grapple fixtures are used on spacecraft or other objects to provide a secure connection for a robotic arm.
North America
The fixtures allowed the Space Shuttle's Canadarm (also known as the Shuttle Remote Manipulator System, or SRMS) to safely g ...
. 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.[''The structure of Canadarm'']
/ref>
Service history
A simulated Canadarm installed on the was seen when the prototype orbiter's payload bay doors were open to test hangar facilities early in the Space Shuttle program. The Canadarm was first tested in orbit in 1981, on 's STS-2
STS-2 was the second Space Shuttle mission conducted by NASA, and the second flight of the orbiter ''Columbia''. The mission, crewed by Joe H. Engle and Richard H. Truly, launched on November 12, 1981, and landed two days later on November 14, ...
mission. Its first operational use was on STS-3
STS-3 was NASA's third Space Shuttle mission, and was the third mission for the Space Shuttle ''Columbia''. It launched on March 22, 1982, and landed eight days later on March 30, 1982. The mission, crewed by Jack R. Lousma and C. Gordon Ful ...
to deploy and manoeuvre the Plasma Diagnostics Package. Canadarm subsequently flew on more than 90 missions with all five orbiters.
Since the installation of the Canadarm2
The Mobile Servicing System (MSS), is a robotic system on board the International Space Station (ISS). Launched to the ISS in 2001, it plays a key role in station assembly and maintenance; it moves equipment and supplies around the station, supp ...
on the International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...
(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.
Retirement
The Canadarm's 90th and final Shuttle mission was in July 2011 on STS-135
STS-135 ( ISS assembly flight ULF7) was the 135th and final mission of the American Space Shuttle program. It used the orbiter ''Atlantis'' and hardware originally processed for the STS-335 contingency mission, which was not flown. STS-135 la ...
, delivering the ''Raffaello'' MPLM
A Multi-Purpose Logistics Module (MPLM) is a large pressurized container that was used on Space Shuttle missions to transfer cargo to and from the International Space Station (ISS). Two MPLMs made a dozen trips in the Shuttle cargo bay and init ...
to the ISS and back. It is on display with ''Atlantis'' at the Kennedy Space Center Visitor Complex
The Kennedy Space Center Visitor Complex is the visitor center at NASA's Kennedy Space Center on Merritt Island, Florida. It features exhibits and displays, historic spacecraft and memorabilia, shows, two IMAX theaters, and a range of bus to ...
. ''Discoverys Canadarm is displayed next to it in the National Air and Space Museum's Udvar-Hazy Center. ''Endeavour'' left its OBSS at the International Space Station as part of its final mission
"Final Mission" is the 83rd episode of the American science fiction television series '' Star Trek: The Next Generation'', and the ninth episode of the fourth season.
Set in the 24th century, the series follows the adventures of the Starfleet ...
, while its Canadarm was originally going to be displayed in the headquarters of the Canadian Space Agency
The Canadian Space Agency (CSA; french: Agence spatiale canadienne, ASC) is the national space agency of Canada, established in 1990 by the ''Canadian Space Agency Act''.
The president is Lisa Campbell, who took the position on September 3, 2020 ...
(CSA).[ However, ''Endeavour''s Canadarm is now on permanent display at the Canada Aviation and Space Museum in ]Ottawa
Ottawa (, ; Canadian French: ) is the capital city of Canada. It is located at the confluence of the Ottawa River and the Rideau River in the southern portion of the province of Ontario. Ottawa borders Gatineau, Quebec, and forms the core ...
. 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.
Derivatives
Canadarm2
Based on the Canadarm1, the larger Canadarm2
The Mobile Servicing System (MSS), is a robotic system on board the International Space Station (ISS). Launched to the ISS in 2001, it plays a key role in station assembly and maintenance; it moves equipment and supplies around the station, supp ...
is used for berthing the trusses, berthing the commercial vehicles, and inspecting the whole International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...
.
Canadarm3
The smaller Canadarm3 will be used for berthing the modules and inspecting the Lunar Gateway
The Lunar Gateway, or simply Gateway, is the first planned extraterrestrial space station in lunar orbit intended to serve as a solar-powered communication hub, science laboratory, and short-term habitation module for government-agency astr ...
.
In popular media
* On November 13, 2012, Google Canada displayed a doodle
A doodle is a drawing made while a person's attention is otherwise occupied. Doodles are simple drawings that can have concrete representational meaning or may just be composed of random and abstract lines or shapes, generally without ever lift ...
on its home search page to celebrate the 31st anniversary of the Canadarm's first use in space.
See also
* List of Canadian inventions and discoveries
Canadian inventions and discoveries are objects, processes, or techniques—invented, innovated, or discovered—that owe their existence either partially or entirely to a person born in Canada, a citizen of Canada, or a company or organizatio ...
*
*
*
*
*
References
External links
NASA:''RMS: PAYLOAD DEPLOYMENT AND RETRIEVAL SYSTEM''
Canadian Space Agency : Canadarm
{{Space Shuttle
Spacecraft components
Space program of Canada
Science and technology in Canada
Space Shuttle program
Space robots
Robotic manipulators
1981 robots