A vehicle height adjustment device includes: a pressure tank capable of storing air in a compression state; a plurality of vehicle height adjustment units that are provided in correspondence with wheels of a vehicle and individually adjust vehicle heights at the respective wheels by supplying the air from the pressure tank or returning the air to the pressure tank; an information acquisition unit that acquires turn route information during travel of the vehicle; and a control unit that raises the vehicle height at the vehicle height adjustment unit on a turn outer side more than the vehicle height at the vehicle height adjustment unit on a turn inner side such that the vehicle takes a tilt posture on the basis of the turn route information when the vehicle turns.

A suspension system S according to the present invention is configured to control actuators A.sub.FR, A.sub.FL, A.sub.RR, A.sub.RL by determining a pitch damping force F.sub.P and a roll damping force F.sub.R to cancel roll and pitch moments M.sub.P, M.sub.R of a body B, and determining target control forces F.sub.TFR, F.sub.TFL, F.sub.TRR, F.sub.TRL in consideration of the pitch damping force F.sub.P and the roll damping force F.sub.R. When the pitch damping force F.sub.P and the roll damping force F.sub.R are output to the actuators A.sub.FR, A.sub.FL, A.sub.RR, A.sub.RL, the actuators A.sub.FR, A.sub.FL, A.sub.RR, A.sub.RL can each generate a control force for cancelling a force acting on the body B not later but preliminarily.

A vehicle height adjustment device includes: a pressure tank capable of storing air in a compression state; a plurality of vehicle height adjustment units that are provided in correspondence with wheels of a vehicle and individually adjust vehicle heights at the respective wheels by supplying the air from the pressure tank or returning the air to the pressure tank; an information acquisition unit that acquires turn route information during travel of the vehicle; and a control unit that raises the vehicle height at the vehicle height adjustment unit on a turn outer side more than the vehicle height at the vehicle height adjustment unit on a turn inner side such that the vehicle takes a tilt posture on the basis of the turn route information when the vehicle turns.

A suspension system for a vehicle, includes (a) a shock absorber disposed between a sprung portion and an unsprung portion and having a damping-force changing mechanism, the shock absorber being configured to generate a damping force with respect to a relative movement of the sprung portion and the unsprung portion such that the magnitude of the damping force is changeable, and (b) a controller configured to control the damping-force changing mechanism. The controller includes a target sprung-speed determining portion configured to determine, as a target sprung speed, a speed of the sprung portion in a behavior of a body of the vehicle that matches an operation input to the vehicle by a driver, for permitting the behavior to match the operation input, the controller being configured to control the damping force such that the speed of the sprung portion becomes equal to the target sprung speed.

A computer-implemented method for controls stability of a vehicle, being a truck or tractor and at least one trailer comprising at least two wheel axles and an electronically controllable suspension system. The method identifies a possible instability state of the vehicle; determines a type of an event that has caused the possible instability state; determining one or more actions comprising adjusting a load distribution between the at least two wheel axles of the trailer based on the possible instability state and based on the type of the event that has caused the possible instability state; and generates and sending a control command to the suspension system to perform the actions. The actions may comprise adjusting the load distribution between the at least two wheel axles of the trailer such that a load on a rear axle is increased and a load on a front axle is decreased.