Machine guns or missiles, I forget which.
Yes, in game he's motorized like a Segway. In-game he's also perfectly upright at all times, which is not terribly realistic...
The crux of my question is, if motorized and if his CoM is always on-axis, is movement possible for Axel. If he has a CoM...
The Twisted Metal video game series includes a character aptly named Axel, whose vehicle is just himself strapped to a pair of tractor wheels. This is the guy:
Most of my friends assume that in real life, he probably wouldn't be able to drive anywhere unless his feet were incredibly heavy, so...