Abstract: A terrain disruption device includes an air or gas flow generation device mounted on a remote operated vehicle having an extendible arm, wherein the air or gas flow generation device includes an elongate (optionally detachable) ducting arrangement to direct the air or gas flow and an optional nozzle. The air or gas flow generation device and/or the elongate ducting arrangement may be mounted on the extendible arm. Preferably, the air or gas flow generation device is powered by a fan, more preferably an electric ducted fan.

Abstract: Embodiments of the invention provide a system and method for operating a pressure-driven pool cleaner. The system includes a hydraulic timer assembly and a venturi vacuum assembly. The method includes directing water to the hydraulic timer assembly and the venturi vacuum assembly, driving the pressure-driven pool cleaner with the hydraulic timer assembly according to a timed movement cycle including a combination of backward movement and forward movement, and suctioning debris with the venturi vacuum assembly. The venturi vacuum assembly is independent of the hydraulic timer assembly so that suctioning occurs during the backward movement and the forward movement.

Abstract: A method for compensating a steering system exhibiting dead-zone characteristics estimates the dead-zone parameters of the steering system and establishes a dead-zone inverse function utilizing the estimated parameters. The dead-zone inverse is utilized to transform steering orders in the dead-zone. Parameters of the dead-zone inverse are continuously up-dated with the utilization of the transformed steering order, the existing dead-zone parameters, and the present heading.