Common Berthing Mechanism
 | This article relies largely or entirely on a single source. (May 2009) |
The Common Berthing Mechanism (or CBM) is used to connect all non-Russian pressurized modules of the International Space Station.
The Common Berthing Mechanism consists of two components: the Active Common Berthing Mechanism (ACBM) and the Passive Common Berthing Mechanism (PCBM).[1] Once connected, the two sides of the CBM form a pressure tight seal, which provides automatic transfer of electricity, communications, and fluid. The CBM also provides a 50 inch (127 cm) passage for the crew. Since this is large enough to allow International Standard Payload Racks to be moved through, payloads can be pre-configured in racks and transported to the station aboard the Multi-Purpose Logistics Modules, which use CBM berthing.
The Common Berthing Mechanism was first used to connect the Unity Module and the Z1 truss of the International Space Station. The Node elements of ISS all mostly use the active CBM, with just 1 or 2 ports out of each of the nodes featuring passive nodes.
The CBM is to be used as a docking mechanism for future spacecraft, including the unmanned Japanese H-II Transfer Vehicle (HTV), a Cygnus resupply vehicle, and the SpaceX Dragon capsule. However, it will not be used for the new Orion.