A roll vibration damping control system includes an electronic control unit configured to: compute a sum of a product of a roll moment of inertia and a roll angular acceleration of a vehicle body, a product of a roll damping coefficient and a first-order integral of the roll angular acceleration, and a product of an equivalent roll stiffness of the vehicle and a second-order integral of the roll angular acceleration, as a controlled roll moment to be applied to the vehicle body; compute a roll moment around a center of gravity of a sprung mass as a correction roll moment, the roll moment being generated by lateral force on wheels due to roll motion; and compute a target roll moment based on a value obtained by correcting the controlled roll moment with the correction roll moment.

A system for filling a tank of a suspension system with hydraulic fluid includes: a module configured to turn on an external pump and pump hydraulic fluid into the suspension system, where the external pump is separate from the suspension system and is configured to pump hydraulic fluid into the suspension system via a port fluidly connected to a hydraulic line of the suspension system; and a fill module configured to, after operating the external pump, operate a pump of the suspension system and pump hydraulic fluid from the hydraulic line into the tank of the suspension system thereby filling the tank.

A suspension system and associated control methods for improving the effectiveness of driver assistance systems is disclosed where the driver assistance systems can generate and send requests to a suspension control unit (SCU) of the suspension system to actuate (e.g., close) one or more comfort valves in the suspension system to increase the roll stiffness and/or pitch stiffness of the suspension system when the driver assistance systems are taking corrective action. As part of a two-way communication between the suspension control unit (SCU) and the driver assistance systems, the suspension control unit (SCU) communicates target stiffnesses and/or calculated effective stiffnesses to the driver assistance systems, which is used to update the vehicle stability models used by the driver assistance systems.

An air management system for a vehicle having a first pneumatic circuit and a second pneumatic circuit, in which the first and second pneumatic circuits are pneumatically connected in a neutral position via a cross-flow mechanism. The first pneumatic circuit includes a first leveling valve configured to adjust independently the height of a first side of the vehicle. The second pneumatic circuit includes a second leveling valve configured to adjust independently the height of a second side of the vehicle. The first and second leveling valves are configured to establish pneumatic communication between the first and second pneumatic circuits when the first leveling valve is not independently adjusting the height of the first side of the vehicle and the second leveling valve is not independently adjusting the height of the second side of the vehicle.

A road surface condition is determined appropriately. A road surface determining section (84) configured to determine a road surface state includes a threshold setting section (845) configured to set a threshold for determining the road surface state, so that a value of a desired control variable is multiplied by a coefficient determined in accordance with a result of the determination by the road surface determining section (84).

A technology can be realized which increases the sense of unity with a vehicle that is felt by a driver. A suspension control device, which controls the damping force of the suspension of a vehicle, comprises a target control amount calculation unit which sets a target control amount, that is referenced when controlling the damping force of the suspension, such that the period of the phase of the roll angle and the period of the phase of the pitch angle of the vehicle approach a synchronized state, such that the magnitude of the expansion-side damping force is greater than the magnitude of the contraction-side damping force on the front-wheel-side of the vehicle, and such that the contraction-side damping force is greater than or equal to the expansion-side damping force on the rear-wheel-side of the vehicle.

Included are an electromagnetic actuator which includes an electric motor configured to generate drive forces for a damping operation and a telescopic operation; an information acquirer which acquires a stroke velocity of the electromagnetic actuator; a drive force arithmetic part which includes a damping force calculator configured to calculate a target damping force and a telescopic force calculator configured to calculate a target telescopic force, and which obtains a target drive force based on the target damping force and the target telescopic force; and a drive controller which controls drive of the electric motor using the target drive force. The drive force arithmetic part includes an adjuster which performs an adjustment to reduce a telescopic control amount for the target telescopic force based on the stroke velocity acquired by the information acquirer.

A method for controlling axle load distribution of a heavy-duty vehicle during a maneuver, wherein the heavy-duty vehicle comprises a number of wheel axles and one or more motion support devices arranged to adjust a relative axle load of one or more wheel axles of the number of wheel axles, the method comprising obtaining a vehicle model and a tire model, wherein the vehicle model and the tire model are jointly configured to predict a tire scrubbing force in dependence of a vehicle state comprising a relative axle load distribution during the maneuver, determining a nominal tire scrubbing force for a current relative axle load distribution, determining an improved relative axle load distribution maneuver associated with a reduced tire scrubbing force compared to the nominal tire scrubbing force, and controlling the one or more motion support devices to provide the improved relative axle load distribution during the maneuver.

A work vehicle includes a vehicle body, running gear to cause the vehicle body to travel, a height adjuster to change a height of a center of gravity of the vehicle body, and a controller configured or programmed to, in accordance with at least one of a turning radius and an angular velocity of the vehicle body during a turn, control the height adjuster to maintain or lower the height of the center of gravity.

A steerable vehicle suspension can include an axle, at least one retractor having a length that decreases in response to a pressure increase applied to the retractor, and at least one wheel spindle. Resistance to rotation of the wheel spindle relative to the axle increases in response to the pressure increase applied to the retractor. A method of operating a steerable vehicle suspension of a vehicle can include allowing steering knuckles rotatably mounted at opposite ends of an axle to rotate relative to the axle while the vehicle moves forward, and applying an inwardly directed force simultaneously to each of the steering knuckles. Another steerable vehicle suspension can include two rotatably mounted steering knuckles, and two retractors connected to the steering knuckles. An inwardly directed force is applied by each retractor to a respective one of the steering knuckles in response to pressure applied to the retractors.