Systems and apparatuses include a hydraulic suspension system including a front suspension actuator, and a front suspension pressure sensor associated with the front suspension actuator; a tire inflation system; and one or more processing circuits comprising one or more memory devices coupled to one or more processors, the one or more memory devices configured to store instructions thereon that, when executed by the one or more processors, cause the one or more processors to: determine a dynamic weight based on information received from the front suspension pressure sensor of the hydraulic suspension system, determine a current front axle lead ratio based on the dynamic weight, determine a target front axle lead ratio, and control operation of the tire inflation system to adjust from the current front axle lead ratio to the target front axle lead ratio.

An off-road vehicle has two front wheels and two rear wheels, the rear wheels being connected to a spool gear driven by a motor. The vehicle also has a left front brake, a right front brake and a single rear brake. Speeds of left and right front wheels are respectively monitored by left and right front speed sensors. A single sensor monitors a common speed of left and right rear wheels. Two user actuated braking input devices, for example a hand lever and a foot lever, may be used independently or concurrently to provide a braking command. An anti-lock braking system may use speed measurements from the various speed sensors to control selective application of pressure on the left front brake, the right front brake and the rear brake.

An electronic control suspension apparatus for controlling a damping force of a damper installed at each of a front wheel and a rear wheel includes: a reception unit configured to receive a vehicle manipulation signal; a driver tendency analysis unit configured to calculate a driver tendency analysis value by analyzing a driver's driving tendency based on the vehicle manipulation signal received by the reception unit; a driver mode determination unit configured to determine a driver mode to which the driver tendency analysis value calculated by the driver tendency analysis unit belongs; and a damping force control unit configured to control the damping force of the damper by changing a current value to be applied to a solenoid valve according to the determined driver mode.

A vehicle height adjustment device includes a changer, a detector, and a controller. The changer is configured to change a relative position of a body of a vehicle to an axle of a wheel of the vehicle. The detector is configured to detect the relative position. The controller is configured to control the changer to change the relative position based on a detection value detected by the detector so as to control a height of the body as a vehicle height. The controller is configured to control the changer to maintain the vehicle height when there is a possibility of a malfunction in the detector.

A trailer having a liftable first axle and an air suspended second axle includes a controller, a first valve coupled to the first axle and a second valve coupled to the second axle. The controller receives an air suspension exhaust request signal and a pressure signal from an air suspension bellows coupled to the second axle. The controller transmits an air suspension control signal to the second valve in response to the air suspension exhaust request signal and transmits a lift axle control signal to the first valve to lower the first axle in response to the pressure signal being less than a predetermined pressure value.

A vehicle height adjustment device includes a changer and a controller. The changer is configured to change a relative position of a body of a vehicle relative to an axle of a wheel of the vehicle. The controller is configured to control the changer to make the relative position a target value so as to control a vehicle height of the body. The controller is configured to control the changer to maintain the relative position when there is a possibility of a malfunction in a detector configured to detect a parameter for control.

A damper control apparatus for controlling a front damper at a front wheel and a rear damper at a rear wheel. The damper control apparatus includes: a preview sensor configured to detect a road surface state in front of a vehicle; a steering angle sensor configured to detect a steering angle of the vehicle; and a controller configured to control the front and rear dampers based on a detected value of the preview sensor. In response to the steering angle sensor detecting a steering angle that exceeds a predetermined steering angle threshold, the controller is configured to reduce control of the rear damper that is based on the detected value of the preview sensor.

Provided is a control device for a steer-by-wire steering mechanism, the control device including: a tire lateral force detection unit configured to detect tire lateral forces acting on left and right wheels; and a toe angle control unit configured to control toe angles of left and right wheels independently of each other such that the detected tire lateral forces become target lateral forces. Not during deceleration, the toe angle control unit sets target lateral forces FLt and FRt such that the total sum of the left and right target lateral forces is not changed and the total sum of absolute values thereof is decreased, and during deceleration, the toe angle control unit sets the target lateral forces FLt and FRt such that straight traveling stability can be obtained.

A road surface condition is determined appropriately. A road surface determining section (84) configured to determine a road surface condition with reference to a wheel speed signal indicative of wheel speeds includes a band-stop filter (841) which acts on the wheel speed signal and has a cutoff frequency band which is changed in accordance with the wheel speed signal.

A signal processing apparatus (20) is a signal processing apparatus for a suspension control apparatus and includes a first determination unit (41). The first determination unit (41) is configured to select any one of a plurality of detection signals including information regarding unsprung vibrations of a first wheel, which are acquired from a plurality of sensors mounted on a vehicle, and determine unsprung vibrations of the first wheel on the basis of the selected one detection signal.