This video shows a close-in view of the drive and steering action of the front wheel drive I built for my R2-D2 replica. The custom built hub motor uses two planetary gearsets driven by an Amplow E30-150 motor.
It is clear to see that the 6" pbeumatice tire achieves full rotation within the standard footshell once the backsides of the side detail panels are hollowed out. This is possible only because it rotates on the center of its own axis, being steered by a surplus Denso right angle gearmotor, which is mounted in the base of the droid and connected through a shaft and universal joint through the ankle.