A vehicle suspension system comprising a hydropneumatic strut comprising a fluid interface, where supply of hydraulic fluid to the strut via the fluid interface causes the overall length of the strut to increase, and withdrawal of hydraulic fluid via the fluid interface causes the overall length of the strut to decrease, a first displacement system in fluid communication with the fluid interface, capable of supplying and withdrawing fluid to and from the strut as well as measuring the volume of fluid supplied or withdrawn from the strut, a second displacement system in fluid communication with the fluid interface, and a hydraulic fluid source for selectively supplying or withdrawing hydraulic fluid from the hydropneumatic strut via either of the first or second displacement systems.

A vehicle suspension system comprising a hydropneumatic strut comprising a fluid interface, where supply of hydraulic fluid to the strut via the fluid interface causes the overall length of the strut to increase, and withdrawal of hydraulic fluid via the fluid interface causes the overall length of the strut to decrease, a first displacement system in fluid communication with the fluid interface, capable of supplying and withdrawing fluid to and from the strut as well as measuring the volume of fluid supplied or withdrawn from the strut, a second displacement system in fluid communication with the fluid interface, and a hydraulic fluid source for selectively supplying or withdrawing hydraulic fluid from the hydropneumatic strut via either of the first or second displacement systems.

An electric vehicle comprises: a main battery which is disposed under the floor of a vehicle interior; a front seat which is provided for a front part of the vehicle interior; a front housing chamber which is formed under a seating surface of the front seat; and an air-suspension device including an air spring which is made to expand and contract by air pressure, an air compressor which compresses air, and one or more first surge tanks which store high-pressure air or low-pressure air, in which the first surge tanks and the air compressor are disposed in a front housing chamber.

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.

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.

A vehicle fluid spring system is adapted to absorb road shock imparted onto at least one road wheel of a vehicle. The vehicle fluid spring system includes a fluid spring and a variable volume unit. The fluid spring includes a fluid chamber adapted to change in volume. The variable volume unit including a rigid piston cylinder, a piston, a fluid cavity, and an actuator. The piston is adapted to reciprocate within, and is in sliding contact with, the rigid piston cylinder. The fluid cavity is defined by the piston cylinder and the piston. The actuator is adapted to drive the piston changing a volume of the fluid cavity. The fluid cavity is in fluid communication with the fluid chamber.

A vehicle fluid spring system is adapted to absorb road shock imparted onto at least one road wheel of a vehicle. The vehicle fluid spring system includes a fluid spring and a variable volume unit. The fluid spring includes a fluid chamber adapted to change in volume. The variable volume unit including a rigid piston cylinder, a piston, a fluid cavity, and an actuator. The piston is adapted to reciprocate within, and is in sliding contact with, the rigid piston cylinder. The fluid cavity is defined by the piston cylinder and the piston. The actuator is adapted to drive the piston changing a volume of the fluid cavity. The fluid cavity is in fluid communication with the fluid chamber.

When a vehicle's driving situation is a rolling state, a compressor is used to transfer compressed air between left and right air suspensions of front wheels, and a compressor is used to transfer compressed air between left and right air suspensions of rear wheels. The air suspensions of the left and right front wheels and the air suspensions of the left and rear wheels thus independently generate counter rolls. This makes it possible to concurrently perform vehicle height adjustment of the air suspensions of the left and right front wheels and vehicle height adjustment of the air suspensions of the left and right rear wheels, which improves responsiveness in counter roll control.

When a vehicle's driving situation is a rolling state, a compressor is used to transfer compressed air between left and right air suspensions of front wheels, and a compressor is used to transfer compressed air between left and right air suspensions of rear wheels. The air suspensions of the left and right front wheels and the air suspensions of the left and rear wheels thus independently generate counter rolls. This makes it possible to concurrently perform vehicle height adjustment of the air suspensions of the left and right front wheels and vehicle height adjustment of the air suspensions of the left and right rear wheels, which improves responsiveness in counter roll control.

A method for operating a pressure control system in a vehicle includes controlling a flow-control valve in a charging line, which conveys a charging pressure medium, in dependence upon an admission pressure and/or upon an admission volume flow. The admission pressure and/or the admission volume flow characterizes a prevailing or currently to be expected loading of a pneumatic consumer of the pressure control system during the supply of the charging pressure medium with a charging volume flow and at a charging pressure into the pneumatic consumer. The method further includes adjusting a flow-control cross-section, which acts on the charging pressure medium as it flows through the flow-control valve, or adjusting an average flow-control cross-section so as to limit the charging volume flow to a limit volume flow. The method additionally includes outputting the volume-flow limited charging pressure medium to the pneumatic consumer.