Ratchet is one of the main character's of Transformers Animated. Initially a civilian mechanic, Ratchet was left bitter and cynical after experiencing the Great War. After the war, he got himself placed in a dead end position of repairing space bridges, seeing it as a chance to get away from what he had experienced. And in his experience, "hero" is another word for casualty, because that's what most of the heroes ended up being. Still, he knows one when he sees it, and Optimus Prime definitely is one.
His main "weapons" are two electromagnets that can extend from his forearms. With them, he can move metal-based objects, levitate downward from great heights, manipulate or tear apart metallic objects in midair, or create magnetic shields. More recently, he won his electromagnetic pulsegenerator back from Lockdown the bounty hunter, a device capable of knocking out a Transformer.
He enjoys grumbling about almost everything, being sarcastic, and having war flashbacks, just like any old man. He was also voiced by Corey Burton who does a lot of characters including Spike Witwicky.