Full Body Drum
Real Life examples: Barber-ous (1&2)
RA2 examples:
(with wheels): Scavenger, The Wreckoning
(without wheels): Walk Smash Walk II
Full Body Drums are a robot related to crawlers but with shell spinner-like weapons.
They generally do use only 2 drive motors, and then add discs, extenders and weapons in a way that the chassis is enclosed in 2 shells with weapons on the outside.
Two variations do exist. The one without wheels (you must use the largest possible however) has weapons that touch the ground, making it really just an unusual crawler. The one with wheels (attached to the drive motors as well) must touch the ground with the wheels, not the shell/weapons. Benefit of wheels include highly increased grip and speed.
They also can use a thwacker-style tail for stabilizing the chassis or for use as a Torque reaction hammer weapon.