Cosmos is an Autobot who turns into a UFO-type spaceship. That's... about all that's known about him.
Whether he's an oddball remains to be seen.
IDW movie comics continuity
Cosmos was present on the command bridge of the Ark when the vessel was being readied to launch and intercept the All Spark and Megatron. He did not get a station in the Star Destroyer-like sunken console pit; instead he got to stand around topside, like one of the officers. Centuries later, following the defeat of Megatron, Cosmos was part of a team of Autobots led by Arcee. While in orbit of Mars, he reported the arrvial of Starscream in the planet's atmosphere to the Arcee and the rest of the group on the planet's surface.