The IBA is comprised of the following parts:

Transitions
Each subassembly component of the IBA (the forward, mid, and aft transition) is made up of a cylindrical aluminum extrusion machined to a very fine tolerance. These transitions serve as the structural support between the two booms, as well as the mechanical interface to the grapple fixtures and the sensor suite.

Booms
Graphite-epoxy booms link the forward, mid, and aft transitions to the upper and lower arm booms. The upper arm boom is approximately 16 ft. long by 13.0 in. in diameter comprising 16 plies phite-epoxy (each ply is .005" thick) for a total weight of just under 50 lbs. The lower arm boomof gra is approximately 19 ft. long by 13.0 in. in diameter comprising 11 plies of graphite-epoxy for a total weight of just over 50 lbs. Each boom is protected with a Kevlar bumper (the same material used in bullet proof vests) to preclude the possibility of dents or scratches on the carbon composite.

Wiring Harness
Just as the arm booms link the forward, mid, and aft transitions mechanically, the wiring harness (electrical cabling) accomplishes the same thing electrically. The wiring harness routes electrical power, data and video to the sensor suite on the aft transition. This link continues back to the cabin of the Space Shuttle, where astronauts control the actions of the Shuttle's robotic arm.

Grapple Fixtures
The IBA design makes use of existing grapple fixtures on both the forward and the mid transitions. The forward transition sports a modified Electrical Flight Grapple Fixture as an interface to the Shuttle arm. The mid transition has a Flight Releasable Grapple Fixture as an interface to the Space Station arm.

Closed Circuit Televisions (CCTV)
The IBA has no cameras installed along the boom. The Shuttle arm, however, has one at the elbow joint and one at the wrist joint to monitor clearances. The CCTV cameras are used to aid the astronauts in the positioning of the arm and IBA.

Control System
The movement of the IBA is controlled uniquely by the Shuttle arm, which is in turn controlled by the Space Shuttle's general-purpose computer. The hand controllers used by the astronauts tell the computer what the astronauts would like the arm to do. Built in software examines what the astronauts commanded inputs are and calculates which arm joints to move, what direction to move them in and how fast to move them. As the computer issues the commands to each of the joints it also looks at what is happening to each joint every 80 milliseconds. Any changes inputted by the astronauts to the initial trajectory commanded are re-examined and recalculated and updated commands are then sent out to each of the joints. Arm control software parameters are tailored for optimal scanning performance of the IBA operations. The Shuttle arm control system is continuously monitoring its "health", and should a failure occur, the computer will automatically apply the brakes to all joints and notify the astronaut of a failure condition. The control system also provides a continuous display of joint rates and speeds, which are displayed on monitors located on the flight deck in the orbiter. As with any control system, the computer can be over-ridden and the joints can be operated individually from the flight deck by the astronaut.

Thermal Protection System
The IBA is covered over its entire length with a multi-layer insulation thermal blanket system, which provides passive thermal control. This material consists of alternate layers of Kapton, Dacron scrim cloth and a Beta cloth outer covering. In extreme cold conditions, thermostatically controlled electric heaters (resistance elements) attached to critical electronic hardware are automatically powered on to maintain a stable operating temperature.