On 11 November 1998 Canada joined fifteen countries in space engineering's most challenging venture to date, the construction of the International Space Station.
Originally published in the Canadian Space Gazette, Winter 1999
Near noon that day the Zarya spacecraft thundered off the desert flats of Kazakhstan. Mounted on the module were the first parts of CSA's station hardware to arrive in orbit. That equipment is an element of the Canadian expertise that is critical to the Phase 2 orbital assembly of the station.
To fully understand Canada's role today on ISS, one must start two decades ago with its early involvement in the American shuttle program. Even before the design of the US Space Transportation System was complete NASA sought foreign partners to share in the utilization and cost of the program. Canada assumed the task of developing an orbiter robotic arm while the European nations pursued the Spacelab facility. The final Canadian product was called the Shuttle Remote Manipulator System (SRMS) or Canadarm. The first Canadarm was given to the US as a gift and flown with Columbia on the second mission of the shuttle program. NASA subsequently purchased five more SRMSs along with a service contract. The system proved indispensable on missions involving emergency satellite retrieval, the Hubble repair/upgrade flights, and the Phase 1 Shuttle-Mir dockings. Spar recently upgraded the SRMSs to a capability where they can handle massive station modules and other new demands of the assembly.
The fitness of the fresh Canadarm was put to the test on the first shuttle flight to the International Space Station. As Endeavour inched closer, Nancy Currie deftly used the Canadarm to perform a successful docking between the Unity node while the Zarya spacecraft towered above. I had the fortune of watching a live CNN Interactive videostream of NASA TV during the docking and was truly awed by the event. When Endeavour passed into Earth's shadow the floodlights along the payload bay switched on and illuminated the orbital complex in a cinematic style. As the astronauts connected power cables and other devices outside the new station, I could see the special pattern targets employed by Canadian Space Vision System fastened to the hull
Many years earlier, Canada was invited by the US to join a station program in President Reagan's 1984 State of the Union address. The Prime Minister accepted in March 1985. The Space Station concept went through many incarnations until it arrived at the present design. Canada's involvement continued their line of success in aerospace robotics. The next generation robotic system developed for ISS by CSA and its industry partners has truly unparalleled mobility and dexterity. This Mobile Servicing System (MSS) consists of hardware inside the pressurized cabin, on the station exterior and equipment back on the ground.
The equipment on the exterior is an extension of the sight and touch of the crew via the Canadian Space Vision System (CSVS). Hardware handling that in the past would have been avoided due to restrictions in field of view, lighting, and astronaut or mechanical dexterity is now possible through this interface. Outside the comfort of the astronauts living and working quarters, on the main truss between the solar arrays, works the robotic part of MSS. It has three subsystems; the Mobile Remote Service Base System (MBS), the Space Station Remote Manipulator System (SSRMS) analogous to an arm, and the Special Purpose Dexterous Manipulator (SPDM) analogous to a hand.
As the station grows in size many sections will be unreachable with the Canadarm, so MSS takes over. It will assist in moving modules from the shuttle's belly to their proper mounting points on the orbiting facility and rearrange the module configuration when necessary. During spacewalks the MSS will assist the astronauts with the heavy lifting and allow them to traverse parts of the station without having to crawl across the intervening structures. An excellent example of MSS's mobility is its ability to leave its home along the truss and "inchworm" to far reaching parts of the station. Most importantly, MSS will allow construction to continue between shuttle flights. Under the current ISS launch schedule defined in October 1998, the SSRMS will be launched in April 2000 and the MBS will follow it up two shuttle construction flights later. SPDM will arrive after at an indefinite time where it will fully realize the capabilities of the MSS.
Canada sends one astronaut emissary on a space station mission this year. The second American assembly flight departs for the station in May 1999 with Julie Payette. The crew's assignment is to prepare ISS for the long overdue arrival of the Russian Service Module. They will stock the orbiting lab with "more than 5,000 pounds of supplies to be stored aboard the station for future crews, equipment ranging from laptop computers, a printer and cameras to maintenance tools, spare parts and clothing." They will also install a spacewalk crane, similar to the one aboard Mir, which will allow astronauts to move quickly from one point to another outside the station during construction. The rest of the year's schedule is still in flux. As of 5 February 1999, Atlantis STS-101 leaves on the third shuttle assembly flight in October and could possibly leave the first crew on board. This mission is solely dependent on the timely launch of the Service Module. Discovery follows in December on mission STS-92 carrying the first parts of the truss, communications equipment and another docking port.
The novelty of the first shuttle assembly flight is passed. Ahead of us is the serious but thrilling challenge of more than forty flights lofting half a million kilograms of hardware to an orbit of 400 kilometers altitude. This construction demands astronauts and cosmonauts conducting more EVAs in a five year period than have been done since Aleksei Leonov first left his Voshkod capsule for the vacuum of space in 1965. This could not be attempted without the robotic expertise of the Canadian Space Program.
John P. Kavanagh is a freelance space exploration writer