The R-series originally began with the P2-series astromech droid, which was sold exclusively to the Republic merchant fleet.

Anatomy of an Astromech

The follow is a description of the components you will find an Astromech droid. Different series can have different components

R-Series Dome

Radar Eye Also called the 'main eye,' it's one of the more recognizable dome parts.

Radar Eye Lens The "lens" that is within the Radar Eye

Logic Displays A color matrix display of light for the glowing effect.

PSI (Process State Indicator) The PSI, for most droids, is a two-color fading light panel.

Holoprojector (HP) The original screen used HPs were reading lights from Vickers Viscount airplanes, used in Great Britain beginning in the early 1950s.

Pie Panels These are pie shaped pieces often cut from the dome. These can open to reveal extensions from the dome such as periscopes or lifeform scanners.

Dome Panels These parts of the dome, including the pie panels, may be painted, etched or cut from the dome, and may open by means of servos and hinges.

P5 Picture Panel P5 refers to the name of the panel in the R2 Builders Group blueprints. The panel has an open round-cornered center with shows the aluminum dome underneath. In a scene in the movie Return of the Jedi, the panel glows red.

Dome Bumps These are two small raised domes on the back of the dome.

Dome Ring The dome ring is the lowest ring between the dome and body and is typically metallic in appearance.

R-Series Body

Large Data Port (LDP)

Utility Arms Arms located in the upper middle of the body.

Front Vents The vent internals are different between the top and bottom and include a "housing" known as vent surrounds.

Side Vents "Vents" located on the the side of a droid.

Coin Slots These are usually made in a 'strip' of rectangular pieces that are slotted on the face.

Pocket Vents These are similar in appearance to the side vents, except for a recessed metal pocketed at the bottom of the part.

Coin Returns Named because they resemble a coin return on a vending machine.

Power Couplings These are round ports with a cross pattern in the middle.

Octagonal Ports These are octagonal shaped ports.

Skirt The skirt is located on the base of the body.

R-Series Legs / Feet

Shoulder Horseshoes These are called horseshoes because they resemble an upside down horseshoe.

Shoulder Hub These are aluminum (or aluminum colored) parts mounted in the round hole created by the shoulder horseshoes.

Booster Covers Large structures on the side of the leg that (in the movies) split apart to extend Artoo's rocket boosters.

Leg Struts Cylindrical lathed pipes that insert into, and run the length of, the booster cover. At the top they appear connected to a box on an angle.

Main Leg The main structural part of the leg itself is the base onto which the detail parts are attached.

Shoulder Hydraulics Metallic tube/pipe structure which mount inside the long opening in the shoulder horseshoes.

Shoulder Buttons Small metallic cylinders which mount into the two small openings on the shoulder horseshoes. These each have three holes and resemble metal bottle caps.

Ankle Bracelet Thin metal plate which caps the top of the ankle.

Outer Ankle Sides Also referred to as 'beefy ankle pieces' these refer to the curved portion of the ankle that faces away from the body.

Ankle Details Angular flat parts which are attached to the front and backs of the ankles.

Ankle Cylinder Wedges Triangular shaped wedges which connect the ankle cylinders to the ankle sides.

Ankle Cylinders Metal-colored cylindrical shaped pipes that mount to the ankle.

Ankle Cylinder Holders Crescent-shaped parts which attach to the lower portion of the ankle and cradle the ankle cylinder.

Under Shoulder Details Small structures consisting of a knurled cylindrical shape with smaller pipes attached at a 90 degree angle. Metallic in color, they attach into the recessed area on the undersides of the main leg.

Main Foot Shell Trapezoidal shaped foot covering.

Foot Side Plate Plate which attaches to the foot shell sides, and usually through which the foot motors and drivetrain is accessed. These are usually part of the footshells, and have several detail parts attached to them.

Half Moon Details Half moon shaped part which attaches to the foot side plates.

Foot Details Small raised areas which attach to the side plates.

Battery Boxes Boxes with curved top and bottom sections, which fit into the insides of the outer feet.

Battery Box Harnesses Metallic structures which attach to the upper and lower overhangs on the battery boxes, and give the appearance of latches.

Foot Hoses Braided metal hoses which connect the battery boxes to the outer foot shells.

Knurled Fittings Knurled metallic fittings into which the foot hoses insert.

Foot Strips Thin aluminum strips which attach to the front and back of the feet. On the fronts of the feet, the knurled fittings insert into these foot strips.