A damper assembly has a longitudinal axis and includes a damper housing with a side wall portion and an end wall portion defining a damping chamber containing a quantity of damping fluid. A photon source and a photon receptor are operatively disposed in optical communication with the non-gaseous damping fluid in the damping chamber. The photon source is operable to direct a photon through the non-gaseous damping fluid toward an associated target surface. The photon receptor is operable to receive the photon reflected off the associated target surface through the non-gaseous damping fluid. A sensor suitable for such use as well as spring and damper assemblies and suspension systems are also included.

An air suspension apparatus includes a compressor configured to compress air, a tank configured to store the air, a tank-side suction conduit configured to supply the compressed air in this tank to an intake side of the compressor, a tank conduit connecting a discharge side of the compressor and the tank, an air suspension connected to the discharge side of the compressor via an air drier, an intake electromagnetic valve provided in the tank-side suction conduit, a return electromagnetic valve provided in the tank conduit, and a discharge conduit provided so as to branch off from between the discharge side of the compressor and the air drier and configured to be connected to an atmosphere by opening a discharge electromagnetic valve.

A sensor arrangement for an air suspension system of a vehicle has a change-over valve for each air spring of a vehicle axle or of multiple, adjacent tandem axles, and has a shutoff valve for the air spring of each vehicle wheel of the axle or for each of the air springs on each side of the tandem axles. The respective changeover valve and the shutoff valves are structurally combined in a valve block arranged at a distance from the air springs. For measuring the pressure in each of the bellows of the air springs, pressure sensors are arranged in or on the valve block. Each of the pressure sensors is connected at the output of the shutoff valve associated with the sensor to the connection line of the bellows of the associated air spring or of the bellows of the associated air springs.

A method for controlling an air suspension system of a vehicle includes: a) determining a bellows pressure-time characteristic curve for air admission to and release from the bellows of one air spring or the bellows of a plurality of air springs, the characteristic curve being normalized with the value of a supply pressure in a reservoir for compressed air, b) sensor measurement of a current pressure in the spring bellows of the air springs as well as the current supply pressure immediately before air admission thereto or air release therefrom, c) determining, from the normalized characteristic curve, the opening duration for the associated shutoff valve using the ratio of the measured bellows pressure to the measured supply pressure and the ratio of the provided target pressure to the measured supply pressure, d) opening the associated shutoff valve for the determined opening duration in order to set the provided target pressure.

A method for controlling an air suspension system of a vehicle includes: a) determining a bellows pressure-time characteristic curve for air admission to and release from the bellows of one air spring or the bellows of a plurality of air springs, the characteristic curve being normalized with the value of a supply pressure in a reservoir for compressed air, b) sensor measurement of a current pressure in the spring bellows of the air springs as well as the current supply pressure immediately before air admission thereto or air release therefrom, c) determining, from the normalized characteristic curve, the opening duration for the associated shutoff valve using the ratio of the measured bellows pressure to the measured supply pressure and the ratio of the provided target pressure to the measured supply pressure, d) opening the associated shutoff valve for the determined opening duration in order to set the provided target pressure.

A method of setting the rides height of the air springs and air pressures of the tires, including receiving a user selected setting or preprogrammed ride height settings; sensing a ride height of, and air pressure within, each of the air springs; determining the weight of the vehicle based on the sensed ride height and air pressure within each of the air springs; providing specified ride heights for the left and right front and rear air springs; determining specified air pressures for the left and right front and rear tire inflators, based upon the determined weight of the vehicle and selected setting; inflating the left and right front and rear air springs to the specified ride heights; and inflating the left and right front and rear tires to the specified air pressures.

Methods and systems are provided for an electric heavy-duty vehicle. In one example, a system for the vehicle may include a wheel hub assembly coupled to a frame of the vehicle via a first wishbone arm and a second wishbone arm, and an air spring coupled at opposite ends to a first link and a second link, each of the first link and the second link being pivotably coupled to the frame of the vehicle, the second link further being pivotably coupled to the first wishbone arm. The air spring may be positioned above the wheel hub assembly with respect to the vehicle.

Methods and systems are provided for an electric heavy-duty vehicle. In one example, a system for the vehicle may include a wheel hub assembly coupled to a frame of the vehicle via a first wishbone arm and a second wishbone arm, and an air spring coupled at opposite ends to a first link and a second link, each of the first link and the second link being pivotably coupled to the frame of the vehicle, the second link further being pivotably coupled to the first wishbone arm. The air spring may be positioned above the wheel hub assembly with respect to the vehicle.

A lift axle suspension for a tandem trailer has first and second suspension air bags for first and second axles. There is a lift air bag that, when pressurized, applies a lifting force to lift the second axle relative to the first axle. A first pneumatic circuit supplies compressed air to the first suspension air bag and a diverter valve and is controlled by a height selector valve that is opened and closed based on the ride height of the trailer. The diverter valve selectively supplies compressed air to the second suspension air bag and a pressure regulator that limits air pressure to a predetermined pressure. A second pneumatic supplies compressed air to the lift air bag and is controlled by a pilot valve.

A system and method are provided for configuring suspension ratios in a multi-rear axle vehicle, the vehicle having a drive axle suspension and at least one tag axle suspension, each suspension having one or more air springs. The timing of the performance of an adjustment cycle series of steps for adjusting the suspension height and air spring pressure readings is optimized by monitoring the acceleration of the vehicle and conducting the adjustment cycle steps when the vehicle acceleration is below an acceleration threshold. Additionally, air spring pressure adjustments may be scaled based on a confidence factor of the air spring pressure readings. Finally, a method is provided for configuring suspension ratios in a multi-rear axle vehicle, the vehicle having a drive axle suspension and at least one tag axle suspension, and for adjusting the air suspension pressures.