Patent ID: 8763506

Claim:
A roller system comprising: a frame configured to be pushed by a host vehicle; a plurality of arm assemblies configured to apply force to a surface, wherein the applied force is independent of a weight of the host vehicle, each arm assembly including: an arm pivotably connected to the frame; and a roller assembly pivotably connected to the arm and having a plurality of rollers configured to engage with the surface; and a pressure distribution system configured to adjust the force applied to the surface by each of the plurality of arm assemblies independently of the weight of the host vehicle, wherein the pressure distribution system comprises: a pressure source; a plurality of pneumatic circuits, each pneumatic circuit including a manifold and one or more pneumatic pistons connected to the manifold; and a switch having a plurality of positions for selectively connecting each pneumatic circuit with the pressure source, wherein each switch position corresponds to a different pneumatic circuit, and wherein the switch is configured to automatically cycle through each position at least once a second; wherein each pneumatic piston of the pressure distribution system is connected to an arm assembly and configured to apply a force on the arm assembly when its respective pneumatic circuit is connected to the pressure source by the switch.