Abstract: A method of braking a vehicle which includes ground engaging wheels, and a braking system with ABS capability and including an operator actuated brake control, the ABS becoming operative in response to the operator actuating the brake control, and upon the braking system sensing the slippage or impending slippage of at least one of the ground wheels relative to the ground, to vary the braking force applied to the at least one of the wheels between, in alternative periods, an applied state in which the braking force is applied, and a released state in which the braking force is released, and characterised in that the method includes applying torque to assist acceleration of the wheel at least during periods in which the braking force is released by the ABS.

Abstract: A steering system for a vehicle comprising a steering control to effect mechanical steering of the vehicle, the steering control being mechanically connected via a mechanical steering train, to at least one steerable ground engaging wheel. A power assistor apparatus is present for power assisting the mechanical steering of the vehicle when the operator operates the steering control. The system includes a hydraulic steering actuator which is operable by an electronically controlled hydraulic steering control valve to effect hydraulic power steering of the vehicle independently of the operation of the steering control. The electronically controlled hydraulic steering control valve is operable in response to signals from an electronic controller, the hydraulic steering actuator being supplied with pressurized hydraulic fluid from a supply valve arrangement.

Abstract: A vehicle including a steering system for moving a pair of wheels supported by a wheel support structure relative to a vehicle structure to achieve steering of the vehicle whilst the vehicle is travelling. The system including a pressure source for providing a supply of pressurized fluid through first and second steering valves to fluid operated first and second actuators, each of which includes an actuating member. The steering valves are operator controlled to provide the pressurized fluid, at least when the steering system is in a first operating mode, from both the first steering valve to the first actuator and from the second steering valve to the second actuator to achieve steering. When the steering system is operating in a second operating mode, only one of the first and second steering valves provides pressurized fluid from the source to a respective one of the actuators to achieve steering.

Abstract: A steering system for a vehicle comprising a steering control to effect mechanical steering of the vehicle, the steering control being mechanically connected via a mechanical steering train, to at least one steerable ground engaging wheel. A power assistor apparatus is present for power assisting the mechanical steering of the vehicle when the operator operates the steering control. The system includes a hydraulic steering actuator which is operable by an electronically controlled hydraulic steering control valve to effect hydraulic power steering of the vehicle independently of the operation of the steering control. The electronically controlled hydraulic steering control valve is operable in response to signals from an electronic controller, the hydraulic steering actuator being supplied with pressurised hydraulic fluid from a supply valve arrangement.

Abstract: A vehicle including a steering system for moving a pair of wheels supported by a wheel support structure relative to a vehicle structure to achieve steering of the vehicle whilst the vehicle is travelling. The system including a pressure source for providing a supply of pressurized fluid through first and second steering valves to fluid operated first and second actuators, each of which includes an actuating member. The steering valves are operator controlled to provide the pressurized fluid, at least when the steering system is in a first operating mode, from both the first steering valve to the first actuator and from the second steering valve to the second actuator to achieve steering. When the steering system is operating in a second operating mode, only one of the first and second steering valves provides pressurized fluid from the source to a respective one of the actuators to achieve steering.

Abstract: A method of operating a vehicle is described, in which the vehicle includes a frame structure carrying a ground engaging structure whereby the vehicle may travel over the ground, the ground engaging structure including a pair of steerable wheels which with the vehicle travelling in a travelling direction, are front wheels, and a pair of rear wheels which may each independently be braked by the operation of respective brake devices, the vehicle further including a controller which is capable of providing signals independently to the brake devices of the rear wheels to effect application and release of a selected brake, and the method including sensing the vehicle travelling speed and providing a first input to the controller, sensing steering of the vehicle by the operator and providing a second input to the controller, and where the travelling speed is below a threshold speed, and depending on the direction of steering of the vehicle, the controller applying one of the brakes.

Abstract: A control system for a vehicle, the vehicle including an engine, a variable transmission for varying the transmission ratio between an output member of the engine and a ground engaging drive apparatus, the control system including at least one control apparatus which is operative to provide inputs to a controller, the controller being responsive to inputs from the control apparatus when the control system is operating in a first operating mode, to provide output signals to vary the engine speed, and when the control system is operating in a second operating mode, to provide output signals to vary the transmission ratio without changing the engine speed, and a mode selector control whereby an operator may select the first or second operating mode.

Abstract: A method of braking a vehicle which includes ground engaging wheels, and a braking system with ABS capability and including an operator actuated brake control, the ABS becoming operative in response to the operator actuating the brake control, and upon the braking system sensing the slippage or impending slippage of at least one of the ground wheels relative to the ground, to vary the braking force applied to the at least one of the wheels between, in alternative periods, an applied state in which the braking force is applied, and a released state in which the braking force is released, and characterised in that the method includes applying torque to assist acceleration of the wheel 16-19 at least during periods in which the braking force is released by the ABS.

Abstract: An agricultural vehicle, such as the type commonly known as a tractor, includes a chassis (11), a front axle (18) and a rear axle (40) suspended from the chassis (11) by a rear axle suspension (42-45). The rear axle suspension is preferably non-reactive, and preferably self-leveling. Further, a towing assembly (60) is secured to the rear axle by which a plow may be towed.