Active Body Control ABC
The high-end suspension system.
More detailed information
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Active Body Control (ABC) with crosswind stabilisation allows superior driving dynamics without compromising on comfort through a combination of active suspension and passive damping.
ABC features all-round self-levelling with the same functions as apply with AIRMATIC.
Four computer-controlled spring struts with plunger cylinders virtually eliminate pitching, rolling and vertical movements.
In order to assess the prevailing driving situation, a microprocessor analyses the signals from the lateral, longitudinal and vertical acceleration sensors and from the pressure sensors assigned to each spring strut. The level of the body is determined by level sensors on the control arms of the front and rear axles. Servohydraulic valves then apply the calculated control signals in the form of volumetric oil flow rates which serve to adjust the plunger cylinders.
The engine's pressure supply system provides the servohydraulic valves with hydraulic pressure of up to 200 bar. The constantly available system pressure and the employed accumulators enable Active Body Control (ABC) to respond to initial signs of body movement in a fraction of a second. The blocking valves installed in valve blocks prevent the vehicle from dropping when stationary. An effective concept for cooling and oil supply rounds off the hydraulic design of the system.