The present disclosure relates to a rear-wheel steering system and a controlling method thereof. The rear-wheel steering system includes: a rack configured to transmit a driving force generated from a rear-wheel steering motor to rear wheels; a first correction module configured to, when an engine is started, detect a position of the rack using a displacement sensor and calculate a first correction value that is a difference between the detected position and a neutral position; a second correction module configured to, when the engine is started, detect a position of the rack using a motor position sensor that detects a rotation angle of the rear-wheel steering motor and calculate a second correction value that is a difference between the detected position and the neutral position; a comparison determiner configured to compare the first correction value and the second correction value to determine whether the displacement sensor has malfunctioned; and a steering controller configured to control an operation of the rear-wheel steering motor. Accordingly, it is possible to determine whether an error occurs in the displacement sensor and to return the rack to the neutral position even when the error has occurred in the displacement sensor.

A dump truck has a the holding mechanism that is provided at a lower part of a king pin and that is for holding the suspension arm from below, and the holding mechanism includes: a snap ring protruded from an outer peripheral surface of the king pin and disposed in a peripheral direction of the king pin; a bolt attached detachably at a lower end of the king pin; and a holder fixed to the king pin by the bolt and having a supported surface opposed to the snap ring from above and along the peripheral direction.

A dump truck has a the holding mechanism that is provided at a lower part of a king pin and that is for holding the suspension arm from below, and the holding mechanism includes: a snap ring protruded from an outer peripheral surface of the king pin and disposed in a peripheral direction of the king pin; a bolt attached detachably at a lower end of the king pin; and a holder fixed to the king pin by the bolt and having a supported surface opposed to the snap ring from above and along the peripheral direction.

A omnidirectional power steering system which can be used on wheeled vehicles that can travel on land without relying on tracks, the device comprises horizontal steering motors (1), teeth (2), bearing balls (3), a horizontal rotary disc (4), brake discs (5), a space for rotation of the extended brake discs (6), a rotating shaft (7), fixing members (8), an inner layer of the wheel hub motor (9), a tyre (10), a wheel hub (11), a space for tyre rotation (12), an operation space for replacing the tyre (13), a housing (14), brake calipers (15), an outer layer of the wheel hub motor (16), an A-arm (17), a control box (18), single chip microcomputers (19), a control panel (20), sensors (21), connecting rods (22), each tyre (10) can rotate to any angle independently, and can also be matched with other tyres to rotate a specific angle, the horizontal rotary disc (4) is a horizontal large gear, a wheel hub (11) is arranged in the middle space, and a wheel hub motor is mounted in the wheel hub (11), and the wheel hub motor is divided into the rotating layer and the non-rotating layer, the non-rotating layer is fixed on the horizontal rotary disc (4), the rotating layer of the wheel hub motor vertically rotates the wheel frame to drive the wheels to move forwards and backwards. When a steering wheel steers, a connection to the control box (18) is present, the control box (18) issues a signal to an independent turning power source, so that the independent turning power source controls the horizontal rotary disc (4) to steer horizontally, and the control box (18) controls each steering direction and each angle of the plurality of wheels according to a driver-selected steering mode. The steering system can achieve parallel parking, a 180 degree in situ zero rotation radius U-turn, a movement toward any direction from a static position and oblique movement, and can use a drift mode when steering at high speed and a plurality of wheel steering modes at different speeds. Inner and outer side wheels cooperative steering angles are optimized, and tyre wear-outs are significantly reduced.

A steerable, self-propelled cart for safely delivering heavy loads, such as concrete, within job sites with unlevel, irregular, or sloped terrain. A cargo bucket is tiltable over front drive wheels for transporting and dumping cargo. Hydraulic drive motors driven by a hydraulic pump propel rear wheels at a selectable speed. Steering handlebars rotate a steering column that turns the rear wheels. A throttle cable extending from the handlebars controls the throttle setting by pivoting a throttle lever mounted on the hydraulic pump. Limiting linkages extend from flanges on an anchor bracket secured to the steering column to a bridge on the throttle lever. As the steering column rotates, the limit linkages are wound partially about it, pivoting the throttle lever by pulling on the bridge, reducing pump speed. Heavy steering displacements will retract the throttle lever to reduce cart speed notwithstanding the previous speed setting chosen by the operator via the cable.

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.

An emergency steering control apparatus of a four-wheel independent steering system includes a sensor module to detect a malfunction in a steering system of a vehicle provided with a wheel independent steering system and a processor to, when at least one leading wheel in a direction of movement of the vehicle malfunctions during forward movement or reverse movement of the vehicle, control normal wheels located opposite the at least one malfunctioning wheel in the direction of the movement so that the vehicle turns in an intended direction for emergency parking.

When a second member of a power plant is in a first position with respect to a first member, a first communication port communicates with a fluid pressure supply source and second and third communication ports communicate with first and second pressure chambers of a fluid pressure motor. The second and third communication ports are shut off from a fourth communication port connected to a reservoir. Different positions of the second member result different communication and shut off relationships among the first to fourth ports. The first to fourth communication ports are provided in a plurality of communication port groups each formed by the first to fourth communication ports.

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 present disclosure relates to a rear wheel steering apparatus and a control method thereof, which can detect stick-slip that may occur during the operation of a rear wheel steering (RWS) system, thereby controlling the performance of a motor in a variable manner, and can control the motor to operate in a limited operation mode only when the stick-slip has occurred during the operation of the RWS system, thereby reducing the noise generated by the stick-slip and the shock transmitted to a vehicle.