Dateline: 06/09/02
Canada's Mobile Base System (MBS) was installed on the International Space Station (ISS) during space mission STS-111/UF-2 which launched June 5, 2002.
The Mobile Base System is the second major component of the Mobile Servicing System (MSS) which is essential to the construction, maintenance and servicing of the International Space Station. The first component, Canadarm 2, a bigger and better version of the space shuttle robotics arm, was delivered and installed on the International Space Station in April 2001.
Work Platform on Rails
The Mobile Base System is a movable aluminum work platform to carry Canadarm 2 and other equipment along rails running the length of the space station.
The mobile base fits on the American-built mobile transporter (MT) that runs on tracks around the station. The combination of mobile base and transporter carries construction equipment and supplies, and the Canadarm to lift them, to ten different work sites on the space station.
Canadarm 2 could walk end-over-end to move on the space station, but the installation of the mobile base gives it a greater range. Walking the Canadarm end-over-end tied up both ends when it moved, so it couldn't carry equipment as it changed location. Now, when it rides on the Mobile Base System, Canadarm 2 can carry other objects needed for repair and construction jobs.
Astronauts can also use the Mobile Base System as a platform for spacewalks.
Mobile Base System Features
Major features of the Mobile Base System include:
- Power Data Grapple Fixtures (PDGF) - four anchor points to provide power, computer commands, video signals and data to Canadarm 2 and other robots
- Payload and Orbit Replaceable Unit Accommodation (POA) - used to carry heavy structures, such as trusses
- MBS Common Attach System (MCAS) - carries pallets with lighter loads like tools and scientific experiments.
The Canada Hand
The Canada Hand or Dextre will also ride on the Mobile Base System. Officially called the Special Purpose Dexterous Manipulator (SPDM), the Canada Hand is a small Canadian two-arm robot designed for delicate and precise maintenance tasks. Although it will probably spend most of its time attached to Canadarm 2, when it needs to perform maintenance tasks on Canadarm 2 or when Canadarm 2 is otherwise occupied the Canada Hand can rest on one of the Mobile Base Power Data Grapple Fixtures. The Canada Hand is scheduled to be delivered to the International Space Station in 2007.
