Abstract: An automated guided vehicle (AGV) includes a suspension system for movably coupling wheels of the AGV with its frame. The system includes a rocker pivotally attached to the frame. A drive wheel and casters are mounted to the rocker on opposite sides of the rocker pivot axis so that the drive wheel and the pair of casters move together about the pivot axis in the same rotational direction when the rocker tilts. The system can be employed in a simple and elegant manner to ensure continuous traction between the drive wheel and the ground while protecting the drive unit from overload when the AGV traverses uneven terrain.