The invention relates to a vehicle comprising front and rear axles, one steering mechanism (6) per axle, comprising a cylinder (7) having a body and two pistons, each associated with a rod and dividing the body into a central chamber extending between the pistons and two end chambers, said vehicle comprising a first configuration wherein the wheels (4, 5) of a single axle extend in parallel planes, and a second O-shaped configuration wherein the wheels (4, 5) are arranged on a circle, and a configuration selector. The vehicle comprises, for fluid connection of the cylinders (7) of the steering mechanisms (6) to the source or sources (17, 18) of pressurised fluid, a first circuit (15) of fluid active in the first configuration, and a second circuit (16) of fluid active in the second configuration, the second circuit (16) being, for the cylinder (7) of each steering mechanism (6), configured so that when the central chamber of said cylinder forms an inlet chamber, the end chambers of said cylinder form exhaust chambers, and vice versa, this second circuit (16) of fluid being equipped with a flow divider (25).

A steering shaft for a motor vehicle steering system may be used in connection with a variety of power assistance mechanisms. The steering shaft may comprise a first shaft part and a second shaft part that are rotationally-elastically coupled by way of a torsion bar. In order to transmit torque, the torsion bar may be received in a bore of the first shaft part and coupled to both the first and second shaft parts. In many cases, a first end of the torsion bar is coupled to the first shaft part, and a second end of the torsion bar is coupled to the second shaft part. The torsion bar may be mounted in the bore such that it can be rotated with respect to the first shaft part via a bearing element. In some examples, the bearing element comprises a prestressing element.

The present disclosure is directed to an agricultural tractor. In an agricultural tractor according to the present disclosure, a steering unit is coupled to a coupling target in a power supply room. According to the present disclosure, the efficiency of the assembly of a cabin and a transmission is maintained, and also vibration and noise are reduced in a boarding space.

A steering control system for a work vehicle can include an operator control providing a steering input indicating a curvature heading of the vehicle, a hydraulic steering system responsive to the steering input from the operator control to effect the curvature heading, and a control system configured to detect, based on the steering input from the operator control, a change in a center of rotation of the vehicle, determine, based on the steering input from the operating control, a velocity of the change in the center of rotation of the vehicle, determine, based on the velocity of the change in the center of rotation, a transition steering input to effect a constant curvature heading during a transition period, and command, based on the transition steering input, the cylinder control valve to alter hydraulic flow or pressure to the hydraulic cylinders to steer the work vehicle at the constant curvature heading.

A steering control system for a work vehicle can include an operator control providing a steering input indicating a curvature heading of the vehicle, a hydraulic steering system responsive to the steering input from the operator control to effect the curvature heading, and a control system configured to detect, based on the steering input from the operator control, a change in a center of rotation of the vehicle, determine, based on the steering input from the operating control, a velocity of the change in the center of rotation of the vehicle, determine, based on the velocity of the change in the center of rotation, a transition steering input to effect a constant curvature heading during a transition period, and command, based on the transition steering input, the cylinder control valve to alter hydraulic flow or pressure to the hydraulic cylinders to steer the work vehicle at the constant curvature heading.

A power steering system has a power steering control system configured to control the power steering system, a first power steering pump configured to be driven by a propulsion source of the vehicle, a second power steering pump configured to be driven by the rotation of the wheels of the vehicle. The first power steering pump is a controllable pump operatively connected to the power steering control system and the power steering control system is configured to control said first power steering pump. The first and second power steering pump are connected to a common power steering fluid circuit such that said first and second power steering pump can operate in parallel to simultaneously provide power steering assistance.

A power steering system has a power steering control system configured to control the power steering system, a first power steering pump configured to be driven by a propulsion source of the vehicle, a second power steering pump configured to be driven by the rotation of the wheels of the vehicle. The first power steering pump is a controllable pump operatively connected to the power steering control system and the power steering control system is configured to control said first power steering pump. The first and second power steering pump are connected to a common power steering fluid circuit such that said first and second power steering pump can operate in parallel to simultaneously provide power steering assistance.