Abstract: A system for providing an electrical power and electronic communication link between a tractor and trailer includes a tractor module associated with the tractor and a trailer module associated with the trailer. The tractor module controls a plurality of switching devices operable to switch a corresponding plurality of electrical lines extending between the tractor electrical system and the trailer to one of an electrical power line, a ground line and a communication line. The trailer module similarly controls a plurality of switching devices operable to switch a corresponding plurality of electrical lines extending between the trailer lighting system and the tractor electrical system to one of an electrical system of the trailer a communication line.

Abstract: A control device and system for the operation of a motor vehicle by a single joystick device. The device and system includes a pair of hydraulic cylinders, one connected to and between the vehicle and the brake pedal and the other to and between the vehicle and the acceleration pedal, a position limiting spring located within each hydraulic cylinder, a pressure regulator for maintaining a constant feed pressure from the vehicle's own hydraulic pump, a control valve for each cylinder mounted between the feed source and each hydraulic cylinder which is responsive to input signals provided by the hand operable joystick, a double port hydraulic steering cylinder integrally connected to the steering system and fed by the same hydraulic source, the steering cylinder being regulated by a double port pressure control valve which is also responsive to the same hand operable joystick.