A SCARA robot has a linear vertical axis, two rotary axes that move the two arm linkages in the horizontal plane, and usually one additional axis for the wrist rotation. With a dedicated vertical axis, the vertical motions are smoother and quicker than in a coordinated axis motion. Furthermore, the rigidity of the robot frame is also very high in the vertical axis and the combination of the rotation motions assures a high compliance in the horizontal plane, facts very important in an assembly task.

A SCARA robot has a high repeatability (less than 0.025mm), and has also the highest speed of any other robot configuration (2000 to 5000mm/s). The robot structure is compact, such that the working envelopes are limited (ranges less than 1000mm). The payloads range from 10 to 100kg.

Scara robots are well suited for stacking a single pallet where space is limited. A major "arm" is mounted such that the whole mechanism can move vertically. This arm is also capable of rotational movement. The wrist moves in a rotational manner as well, in order to rotate bags or cases for placement. Scara robots are fast and use little space. They may not be suited for applications that require multiple loading positions or pickup positions.

This robot primarily used in palletizing applications. Other uses such as packaging, welding, gluing, painting and moving heavy parts are also possible. The gantry system is mounted primarily overhead, so it will use little floor space. A gantry system has a very large work envelope and repeatability in the range of 0.1 to 1 mm, which is good considering the large size of the work area. Payloads can vary from a few pounds up to 2000 lbs. Gantry systems are generally slower in both acceleration and deceleration than other types of robotic systems.

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