Electronically controlled hydraulic valves can be directly mounted to rear steering cylinders of a four wheel steering machine to improve steering, reduce space consumption, reduce leak points and allow ease of routing. The valves can receive hydraulic fluid from a pump and release hydraulic fluid to tank, while controlling an amount of hydraulic fluid to the steering cylinder via inlets and outlets in direct contact. The valves can be controlled by a controller that is also in communication with position sensors configured to sense positions of the front and rear steering cylinders, so that the directly mounted valves in the rear can be correspondingly controlled to follow steering in the front.

The assistance device (I) operates in a road mode in which the rear wheels (9) are initially straight and, once the front wheels (II) have turned through a certain steering angle, the rear wheels (9) are controlled to steer proportionately to the steering angle control received by the front wheels (II). This device (I) also operates in a parking mode in which the rear axle (5) steers and in which the steering angle of the rear wheels (9) is controlled via a device (10) for controlling the steering of the rear axle (5). The device then controls the steering of the rear wheels (9), which is dependent on the distance between the vehicle and the platform and other obstacles in the environment. These distances are measured by distance sensors (15, 18, 17, 18).

Hydraulic cylinders controlled by electronic valves can be provided at each rear corner of an agricultural machine to improve four wheel steering. The valves can receive hydraulic fluid from a pump and release hydraulic fluid to tank, while independently controlling an amount of hydraulic fluid to each rear steering cylinder. The valves can be controlled by a controller that is also in communication with position sensors configured to sense positions of the front and rear steering cylinders, so that the rear steering cylinders can be correspondingly controlled to follow the front steering cylinders.

A chassis for a lift device includes a base, an arm coupled to the base and configured to support a tractive element, and a plate extending from the arm at an upward angle. The arm includes a steering actuator interface configured to support an end of a steering actuator for the tractive element. The plate is configured to extend past the steering actuator.

A system and method of controlling a scissors lift vehicle are provided. The system includes a main computer including one or more processors and one or more memory devices communicatively coupled to the one or more processors, a steer controller configured to receive commands from the main computer to control a plurality of independently steerable wheel assemblies, each wheel assembly including a steer angle sensor, a steer angle actuator, and a drive motor, and a scissors lift controller configured to control a hydraulic piston assembly including a hydraulic fluid reservoir internal to a piston rod assembly. The system also includes a tilt sensor configured to determine an angle of incline the scissors lift vehicle, a variable-speed steer actuator configured to rotate a wheel assembly about the steer axis of rotation at a selectable rate, and a wheel including a respective drive axis of rotation.

A method for controlling a wheel axle assembly of a vehicle. The vehicle comprises a vehicle body with a longitudinal axis extending in a longitudinal direction, a transversal axis extending in a transversal direction and a vertical axis extending in a vertical direction. The longitudinal axis, the transversal axis and the vertical axis are perpendicular to each other. The longitudinal direction corresponds to an intended direction of travel of the vehicle and the vertical direction being parallel to a vertical line when the vehicle is positioned on a flat horizontally extending surface. The vehicle body comprises a vehicle body centre plane extending along the longitudinal axis and the vertical axis and separating the vehicle body into two body halves.

The present invention relates to an assembly which includes: a chassis for a mobile land vehicle, in particular an agricultural or public works vehicle; at least two half-crossmembers (21) mounted telescopically on the chassis; wheel mountings (27) pivotably mounted on each one of said half-crossmembers; steered wheels rotatably mounted on said mountings; and a device for controlling the direction of the wheels. The assembly is characterized in that it includes means (39, 41, 47) designed, for a certain position of two half-crossmembers, to increase, upon the pivoting of the wheels, the opening of the said wheels relative to the opening of the wheels resulting from the same pivoting and another position of the two half-crossmembers.

A dump truck includes a suspension and a steering mechanism. The suspension includes: a suspension arm in a form of an upper arm having an up-and-down movable proximal end supported on a vehicle body frame; and a tire support in a form of a casing rotatably attached to a distal end of the upper arm. The steering mechanism includes a steering cylinder having a proximal end attached to the upper arm and a distal end attached to a knuckle arm provided to the tire support.

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 chassis for a lift device includes a base, an arm, and a first actuator. The base has a first end and an opposing second end. The first end defines an arm interface and a pivot actuator interface. The arm includes a longitudinal portion pivotably coupled to the arm interface and a lateral portion extending from the longitudinal portion. The lateral portion defines a second pivot actuator interface. The lateral portion is configured to support a tractive element. The pivot actuator extends between the first pivot actuator interface and the second pivot actuator interface. At least a portion of a bottom surface of the lateral portion has a sloped profile.