The present invention comprises a trailer main frame with a first rocker assembly and a second rocker assembly pivotally attached to the trailer main frame wherein the rocker assemblies are attached to leveling means such as but not limited to hydraulic and or air system between the trailer main frame and the rocker assemblies.

A multi-axle transport trailer having a plurality of axles includes a suspension comprising air bags associated with each axle, the air bags in communication with an air source, wherein air bags associated with different axles are capable of having different air pressures therein. The trailer further optionally includes a steering system associated with at least one axle, the axle including a tie rod connected between wheels on both ends of the axle, the steering system comprising cylinders configured to articulate the wheels, and a sensing device configured to monitor movement of the tie rod and facilitate actuating the cylinders to turn the wheels.

The invention relates to an axle assembly of a heavy goods vehicle, comprising a pivot bearing steering rotational axis (X), a wheel support comprising at least one wheel that is mounted thereon so as to be rotatable about a wheel rotational axis (Z), the wheel rotational axis (Z) being arranged behind the steering rotational axis (X), in the travel direction (V), in every deflection state of the axle assembly, during straight travel, and a unit that is adjustable about the steering rotational axis (X) when the wheel support is rotated, the adjustable unit being adjustable between two operating states, specifically a forwards travel operating state in which it damps the rotational movement of the wheel support about the steering rotational axis (X), and a reverse travel operating state in which it introduces a steering force, which steers the axle assembly, into the axle assembly.

The present application discloses a steering control system, a method and a crane. The steering control system includes: one or more first angle sensors, one or more second angle sensors, and a steering controller; each of the first angle sensors collects an actual steering angle of a wheel corresponding to a mechanical steering axle as a first steering angle; each of the second angle sensors an actual steering angle of a wheel corresponding to an electrically controlled steering axle as a second steering angle; the steering controller obtains a theoretical steering angle of the wheel corresponding to the electrically controlled steering axle in a corresponding travel mode according to the first steering angle, and compares the second steering angle with the theoretical steering angle, to control the wheel corresponding to the electrically controlled steering axle to steer according to a difference therebetween.

The invention relates to an axle assembly and a heavy-duty vehicle having such an axle assembly, which comprises a pivot bearing having a substantially vertically extending steering axis of rotation, a bogie rotatably arranged about the steering axis of rotation, a rocker mounted on the bogie so as to be pivotable about a substantially horizontal pivot axis, a wheel carrier operatively connected to the rocker having at least one wheel rotatably mounted thereon about a wheel axis of rotation, the wheel axis of rotation extending substantially horizontally and, when driving straight ahead, substantially transversely to the direction of travel, and a pneumatically actuatable power device, which is arranged between the rocker and the bogie.

A tractor unit is disclosed for transporting an elongated load such as a wind turbine blade or wind turbine tower segment. The tractor unit body is supported, driven and steered by a wheel set comprising at least three ground-engaging wheels. At least two of the wheels are steerable and can transform between an aligned mode of operation and a carousel mode of operation. In the aligned mode, the wheels are aligned with one another in a neutral steering position, and steerable to vary the direction of steering. In the carousel mode, the wheels of the wheel set are oriented with their axes of rotation intersecting at a substantially common vertical axis located within the lateral extent of the tractor unit body, so that when the wheels are driven the tractor unit spins about this common vertical axis. A load engagement mechanism is mounted pivotally on the tractor unit body about the common vertical axis. This allows the load engagement mechanism to be counter-rotated in an equal and opposite amount to the angular rotation of the tractor unit body in carousel mode, keeping the load in fixed position relative to the ground as the tractor unit spins.

A suspension system is provided comprising at least one ride height valve, when engaged, that allows an air flow to engage a hydraulic control valve such that it initiates either extension or retraction of a hydraulic piston from a cylinder. Extension or retraction of the hydraulic piston causes a booster frame to be bias downwardly or upwardly, respectively. The ride height valve is engaged when a booster axle is at a predetermined distance from the frame.

A suspension system is provided comprising at least one ride height valve, when engaged, that allows an air flow to engage a hydraulic control valve such that it initiates either extension or retraction of a hydraulic piston from a cylinder. Extension or retraction of the hydraulic piston causes a booster frame to be bias downwardly or upwardly, respectively. The ride height valve is engaged when a booster axle is at a predetermined distance from the frame.

The invention relates to an axle assembly of a heavy goods vehicle, comprising a pivot bearing steering rotational axis (X), a wheel support comprising at least one wheel that is mounted thereon so as to be rotatable about a wheel rotational axis (Z), the wheel rotational axis (Z) being arranged behind the steering rotational axis (X), in the travel direction (V), in every deflection state of the axle assembly, during straight travel, and a unit that is adjustable about the steering rotational axis (X) when the wheel support is rotated, the adjustable unit being adjustable between two operating states, specifically a forwards travel operating state in which it damps the rotational movement of the wheel support about the steering rotational axis (X), and a reverse travel operating state in which it introduces a steering force, which steers the axle assembly, into the axle assembly.

The invention relates to an axle assembly and a heavy-duty vehicle having such an axle assembly, which comprises a pivot bearing having a substantially vertically extending steering axis of rotation, a bogie rotatably arranged about the steering axis of rotation, a rocker mounted on the bogie so as to be pivotable about a substantially horizontal pivot axis, a wheel carrier operatively connected to the rocker having at least one wheel rotatably mounted thereon about a wheel axis of rotation, the wheel axis of rotation extending substantially horizontally and, when driving straight ahead, substantially transversely to the direction of travel, and a pneumatically actuatable power device, which is arranged between the rocker and the bogie.