In some examples, a vehicle suspension for supporting, at least in part, a sprung mass, includes a damper connected to the sprung mass, the damper including a movable piston. The vehicle suspension further includes an actuator and a controller. The controller may be configured to determine a frequency of motion associated with the sprung mass. When the frequency of motion is below a first frequency threshold, the controller may send a control signal to cause the actuator to apply a deceleration force to the sprung mass. Further, when the frequency of motion associated with the sprung mass exceeds the first frequency threshold, the controller may send a control signal to cause the actuator to apply a compensatory force to the sprung mass. For instance, a magnitude of the compensatory force may be based on a friction force determined for the damper.

Systems and methods for controlling a gas spring in a suspension system. The suspension system includes a gas spring and an accumulator coupled to the gas spring and having a bladder. The accumulator may be in a compressed state and an uncompressed state based on a pressure difference across the bladder. A target amount of gas in the gas spring is determined. The amount of gas in the gas spring is adjusted towards the target amount of gas in accordance with a pressure difference across the bladder based on the difference between the first pressure and the second pressure.

Provided is a system for estimating behavior of a vehicle to control damping force of a variable damper installed between an axle and a vehicle body. The system includes four dampers installed in wheels, two or more wheel sensors configured to detect vertical velocities of wheels, one integrated sensor installed on one side of the vehicle body, and an electronic control unit (ECU) configured to control damping force of the dampers on the basis of a roll value, a pitch value, and a bounce value of the vehicle body estimated through the integrated sensor and the vertical velocities of the wheels.

A method for operating a pneumatic system having a compressed air supply system and an air spring system includes determining at least one deflection of at least one air spring of the pneumatic system. The air spring is configured to be connected to a gallery in a selectively gas-conveying manner via a valve. The method further includes determining at least one bellows volume of a spring bellows of the at least one air spring based on the at least one determined deflection, indicating a pneumatic surrogate model for the at least one bellows volume and/or for a pressure accumulator volume of a pressure accumulator of the pneumatic system based on a mass flow balance for a balance volume, and calculating, based on the pneumatic surrogate model, at least one pressure value of the at least one bellows volume, the pressure accumulator volume, and/or the balance volume.

Methods and systems for estimating an axle load of a vehicle are described. In one example, a method is disclosed wherein axle load is estimated in response to an angle between two components of an axle. The angle may change as weight is added to or removed from the axle such that axle load may be determined as a function of the angle.

The present invention relates to a method for determining a functional status of a vehicle shock absorber arrangement (100). The method determines a difference between force values during compression and expansion of the vehicle shock absorber arrangement (100), whereby the shock absorber arrangement (100) can be determined to be degraded if the difference is below a predetermined threshold.

A vehicle height control apparatus considering a strong wind traveling situation may include: a strong wind zone determining unit for obtaining wind speed information of a current position by using map information to which the wind speed information is corresponded and current position information of a vehicle, and generating strong wind zone information by comparing the obtained wind speed information with a predetermined reference wind speed to determine a strong wind zone; a strong wind traveling situation determining unit for generating strong wind traveling situation information by determining the strong wind traveling situation based on the strong wind zone information and the vehicle speed information of the current position; and a control signal generating unit for generating a control signal of a vehicle height adjusting device according to the strong wind traveling situation information.

Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

Provided are a vehicle, a vehicle motion state estimation apparatus, and a method for estimating a vehicle motion state capable of highly accurately estimating a state quantity of a bounce motion of a vehicle having a non-linear suspension characteristic. The vehicle motion state estimation apparatus in a vehicle, in which wheels and a vehicle body are coupled via a suspension, includes a bounce motion estimation unit that estimates and outputs a state quantity of a bounce motion of the vehicle based on traveling state information of the vehicle, and a correction value estimation unit that calculates a correction value to correct an output the bounce motion estimation unit. The correction value estimation unit calculates the correction value in consideration of a non-linear characteristic of the suspension.

An electrically powered suspension system includes: an electromagnetic actuator; an information acquisition unit configured to acquire time-series information related to stroke position of the electromagnetic actuator, information on stroke velocity, and an amount of change in stroke of the electromagnetic actuator and information on a stroke direction based on the time-series information; a damping force calculation unit configured to calculate target damping force based on the information on the stroke velocity; and a drive control unit configured to control driving of the electromagnetic actuator using target driving force obtained based on the target damping force. The damping force calculation unit calculates equivalent friction compensation force based on the amount of change in the stroke and the information on the stroke direction, and corrects the target damping force based on the calculated equivalent friction compensation force. The equivalent friction compensation force has elastic force component and dynamic friction force component.