Abstract: A vehicle zone control system may include a tractor having a propulsion unit and a steering unit, at least sensor carried by the tractor and stored data defining a plurality of zones proximate the vehicle. The system determines in which of the plurality of zones a remote operator on ground proximate the tractor currently resides based upon signals from the at least one sensor. The system differently controls at least one of the propulsion unit and the steering unit based upon in which zone the remote operator currently resides.

Abstract: A vehicle may include a movable roof, a sensor supported by the roof, and an actuator for selectively raising and lowering the roof.

Abstract: A pressure release valve, having three or more cavities is described. The pressure release valve comprises a valve body with at least three valve cavities for fluid. The first valve cavity contains high-pressure fluid and the second cavity contains low-pressure fluid. The first, second, and third cavities are separate and apart from one another. The pressure release valve further includes a movable valve body shaft with a valve hammer and an elastic spring body. The pressure release valve further includes a channel and a valve port, wherein when pressure is applied to the movable valve body shaft, the movable valve body shaft is actuated to press against the valve hammer forcing the valve hammer to move opening the port allowing fluid to flow from the first cavity, to the second cavity and the third cavity.