GO-4

GO-4 units are robots built by the Buy 'N Large Corporation tasked with overseeing security operations aboard spacecraft, as well as handling other miscellaneous tasks.

Design
They're quite small, and easily recognizable due to the red police light atop their bodies. GO-4 units are equipped with two salute-ready arms and an anti-gravity stasis beam. For communication the units have various beeps and other sounds. GO-4 units also can deliver coffee to superiors.

Bio in the film
A GO-4 unit served aboard the Axiom as the Captain B. McCrea's first mate, and helped Auto in his attempt to carry out Directive A-113. He was accidently destroyed when he attempted to assist AUTO in taking down Captain B. McCrea and was kicked and sent flying through a window and crashing down.

Trivia

 * GO-4 is a pun on how personal assistants are often referred to as 'Gophers.' A verbal pun as they are often sent to "Go for (GO-4) things.)
 * GO-4 is one of three Pixar characters to fall to his death. He is the second to do so, Emperor Zurg (who actually survived) preceeding him and Charles Muntz following. He is the seventh Disney villain overall to do so. (after the Wicked Queen, Ratigan, McLeach, Gaston, Frollo, and Zurg.)