Canada

Canada became only the third nation to launch a satellite, in 1962. Despite this, Canada maintains no launch facilities of its own and uses NASA facilities within America’s national borders. The civilian Canadian Space Agency (CSA) (in French L’Agence Spatiale Canadienne or ASC) was not established until 1989. Canada co­operates regularly with NASA in America and is a “Co-operating State’’ with the

European Space Agency. By paying into the ESA budget, Canada is given a position on the main committees of the ESA. Canada also provides instruments to fly on European satellites and deep-space probes.

Canada has provided two elements that are vital to the construction of ISS, plus a third which is vital to Space Shuttle survivability in the final years of its service. All three were developed and built under NASA contracts:

• Remote Manipulator System (RMS): Development of the Shuttle’s RMS, popularly referred to as the “Canadarm”, began in 1974, when Canada agreed to develop and build a single RMS for the Shuttle orbiter Columbia. NASA subsequently ordered four more, for the other orbiters. The RMS was 15m long and had two rotating joints (pitch and yaw) at the shoulder, one joint (pitch) at the elbow, and three joints (pitch, yaw, and roll) at the wrist. The two booms were made of graphite epoxy. The upper boom was 5 m long, and the lower boom was 5.8 m long, both were 33 cm in diameter. A single end effector, on the free end, housed three wires that were used in conjunction to grasp special grapple fixtures on the items to be lifted. These wires pulled the payload snug against the end effector and allowed it to be moved around. Shuttle Mission Specialists operated the RMS from the orbiter’s aft flight deck, using either the Shuttle’s own computers to translate hand controller commands into smooth RMS move­ments, or manually, by commanding each rotation joint individually. The RMS was permanently fixed to the Shuttle’s payload bay door hinge-line and is returned to Earth with the orbiter at the end of each flight.

• Space Station Remote Manipulator System (SSRMS), affectionately called “Canadarm-2”, was a more advanced tool than the Shuttle RMS. It was origin­ally designed to grasp the Shuttle and pull it in to dock with Space Station Freedom. The unique feature of the SSRMS was the Latching End Effector (LEE) at each end, which allowed either end to mate to a Power-Data Grapple Fixture (PDGF) on the exterior of ISS, while the free end performed the lifting tasks. This feature also allowed the SSRMS to be “walked” end over end across the exterior of the American sector of ISS, from one PDGF to another. The RMS on a docked Shuttle and the SSRMS were capable of working together, either lifting items out of the Shuttle payload bay, or handing items from one to the other.

The SSRMS was also designed to be mounted on the Mobile Base System, a small cart that could translate along rails mounted on the ram face of the ITS. This additional mobility allowed the SSRMS to support the construction of the ends of the ITS, while being mounted on and travelling along the face of those ITS elements already in place. The reach of the SSRMS was dictated by the necessity to move the Port-6 ITS from its temporary position on the Z-1 Truss and install it on the exposed end of the Port-5 ITS. The SRMS was designed for on-orbit replacement of its major parts and was not expected to return to Earth.

An extension tool, to be used with the SSRMS was the “Dextre” manipulator system. This consisted of two smaller Remote Manipulator Systems that could be used to complete more delicate work on the exterior of ISS without the requirement for crew members to perform EVAs.

• Orbiter Boom Sensor System (OBSS): As a result of the STS-107 tragedy in February 2003, the Columbia Accident Investigation Board recommended that NASA develop a method of inspecting areas of the orbiter that had previously been inaccessible to the crew in flight. The OBSS provided an extension to the Shuttle’s RMS and the cameras and laser sensors on the OBSS allowed the crew to inspect those areas of their spacecraft that were not readily visible from the flight deck windows, or with the cameras on the un-extended RMS. On early flights the OBSS was mounted on the opposite payload bay door hinge-line to the RMS, making it easy for the latter to pick up. It was then returned to that location and carried back to Earth at the end of each flight. In 2007, STS-118 astronauts installed a mounting to allow the OBSS to be stored on the exterior of ISS when the Shuttle is retired in 2010. This would mean that the OBSS was still available to examine the exterior of the ISS for meteorite strikes, or other damage, even when the Shuttle is no longer flying. The Shuttle RMS, SSRMS, and OBSS were all developed and built by Macdonald, Dettwiler & Associates, Limited, Brampton, Ontario.

The first Canadian astronaut flew on the Shuttle in 1984 and was followed by a further 7 Canadian nationals who have taken part in a total of 13 Shuttle flights through the end of 2007. Two further Canadian astronauts have retired without flying in space.

Canada maintains a number of space centres:

• John H. Chapman Space Centre, Saint-Hubert, Quebec was the CSA’s Head­quarters and oversees the management of the national space programme.

• David Florida Laboratory, Ottawa, Ontario, an engineering facility.

• Mobile Servicing System Operations Complex (MOC), Longueluil, Quebec, prepared the Canadian systems and provided astronaut training on Shuttle RMS and SSRMS systems. It also provided full support for all RMS and SSRMS engineering and operations.