Methods and systems are provided for diagnosing a shock absorber coupled to a vehicle tire. In one example, a sensor of a tire pressure measurement system coupled inside a tire is used to measure a tire pressure as well as an oscillatory behavior of the tire. A state of health of a shock absorber coupled to the tire is estimated based on the oscillatory behavior.

A traveling control system for a vehicle includes a first sprung structure acceleration sensor, a second sprung structure acceleration sensor, a third sprung structure acceleration sensor, a fourth sprung structure acceleration sensor, and an electronic control unit. The electronic control unit is configured to calculate a vertical acceleration, a roll acceleration, and a pitch acceleration at a gravity center position, calculate vertical accelerations of a sprung structure at positions of a front right wheel, a front left wheel, a rear right wheel, and a rear left wheel, and control traveling of the vehicle based on the vertical accelerations of the sprung structure at the positions of the front right wheel, the front left wheel, the rear right wheel, and the rear left wheel.

A center-of-mass height estimation device includes a roll moment calculation unit for calculating roll moment of a sprung portion in a vehicle on the basis of bearing capacities of left and right suspensions provided on the vehicle, a lateral acceleration measurement unit for measuring lateral acceleration, which is acceleration in a width direction of the vehicle, a mass measurement unit for measuring mass of the sprung portion, a transfer function calculation unit for calculating a transfer function of the roll moment with respect to the lateral acceleration, and a center-of-mass height calculation unit for dividing the gain of the transfer function by the mass of the sprung portion to calculate a height from a roll center of the vehicle to a center of mass of the sprung portion.

A motion sickness control system for a vehicle includes a vibrator. The motion sickness control system includes a sensor configured to measure vibration of the vehicle. The motion sickness control system includes a computer having a processor and a memory storing instructions executable by the processor to actuate the vibrator at a target frequency based on the measured vibration of the vehicle. The target frequency attenuates the measured vibration of the vehicle.

A method dynamically stabilizes a vehicle having a suspension system including pneumatic air springs, with one air spring being associated with each wheel, each air spring being independently adjustable in height; an air spring valve associated with each air spring; and a reservoir containing a source of air. The method obtains data relating to at least lateral acceleration, yaw rate, roll rate, velocity and the steering wheel angle deviation of the vehicle. Thresholds are established, and the data is compared to the thresholds. If thresholds are exceeded, at least one air spring valve is automatically opened to increase air pressure in the associated air spring by receiving air from the reservoir, or to decrease air pressure in the associated air spring by returning air to the reservoir, so as to adjust a height of the associated air spring to help transfer the weight 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 multi-mode air shock is disclosed herein. The air shock includes an air spring having a primary air chamber, and a damper having an insertion end to telescope within the primary air chamber and a coupler to couple with a portion of a vehicle. An adjuster housing is fixedly coupled to an end of the air spring opposite of the damper, the adjuster housing having a secondary air chamber in communication with the primary air chamber and a mounting structure to couple with a different portion of the vehicle. There is a bulkhead with a valve to open or close the fluid communication between the primary air chamber and the secondary air chamber. The air shock also includes a tertiary air chamber in fluid communication with the secondary air chamber but not in fluid communication with the primary air chamber except via the secondary air chamber.

A suspension device includes: a damping device that damps a force generated between a vehicle body and a wheel of a vehicle; a determination unit that determines whether the vehicle is jumping, using an acceleration of the vehicle in a front-rear direction, an acceleration of the vehicle in a left-right direction, and an acceleration of the vehicle in a vertical direction; and a damping force control unit that increases a damping force of the damping device so as to be greater than the damping force generated when the determination unit does not determine that the vehicle is jumping, when the determination unit determines that the vehicle is jumping.

An air suspension system which includes the ability to adjust the working air volume, pressure, and spring rate of one or more air springs to reduce or eliminate various types of vehicle oscillations. Switchable or variable volume air spring assemblies have the ability to change air spring volumes, which results in changes in air spring rates, and therefore changes in normal loads applied to each wheel. Changes in wheel normal loads change wheel traction (slip) and vehicle dynamics (pitch, roll, yaw displacement, rate and acceleration). The spring rate of one or more of the air spring assemblies is adjusted automatically when a vehicle oscillation is detected. This vehicle oscillation is calculated from the raw vehicle signals, or another vehicle module may detect the oscillation and send a command to the air suspension module to change the spring rates. This changes the natural frequency of the vehicle, dampening the oscillation.

Systems and methods to detect abnormalities within a stabilizer system for a vehicle. A method includes receiving suspension system data from one or more vehicle sensors, calculating a roll gradient from the suspension system data, determining whether the calculated roll gradient is greater than a predetermined roll gradient threshold, and setting a diagnostic notification if the calculated roll gradient is greater than the predetermined roll gradient threshold.