BMW F12 2011 Technical Training Manual page 59

F12￿Chassis￿Dynamics
6.￿Driving￿stability￿control
Index
1
2
3
4
5
6
The￿F12￿features￿the￿Vertical￿Dynamics￿Management￿(VDM)￿with￿integrated￿Electronic￿Damper
Control￿(EDC)￿function.￿The￿EDC￿was￿also￿referred￿to￿as￿Vertical￿Dynamics￿Control￿(VDC)￿in￿the￿large
series￿from￿the￿F01/F02￿onwards.￿The￿VDC￿introduced￿with￿the￿E70/E71￿was￿systematically￿devel-
oped￿further￿for￿the￿F01/F02,￿F10￿and￿now￿the￿F12￿uses￿the￿latest￿version.
The￿EDC￿reduces￿undesirable￿vehicle￿movements￿that￿arise￿as￿a￿result￿of￿a￿dynamic￿driving￿style￿or
uneven￿roadway.￿This￿achieves￿noticeable￿improvements￿in￿the￿following￿areas,￿even￿with￿a￿com-
fort-oriented￿sports￿suspension:
• Vehicle￿body￿comfort
• Tire￿comfort
• Driving￿dynamics.
With￿EDC,￿the￿actuator￿unit￿and￿the￿specified￿satellite￿sensors￿at￿the￿shock￿absorber￿are￿connected￿to
the￿VDM￿control￿unit￿via￿FlexRay.
The￿vertical￿acceleration￿of￿the￿wheel￿is￿recorded￿by￿the￿acceleration￿sensors￿integrated￿in￿the￿satel-
lite.
The￿movement￿of￿the￿vehicle￿body￿is￿determined￿based￿on￿the￿wheel￿acceleration￿and￿ride￿height￿sig-
nals.￿In￿addition,￿signals￿such￿as￿the￿vehicle￿speed￿are￿acquired￿via￿FlexRay￿and￿used￿to￿determine￿the
reference￿forces￿for￿the￿damping￿action.
The￿current￿supply￿required￿for￿the￿rebound￿and￿compression￿stage￿valves￿at￿the￿dampers￿is￿switched
based￿on￿the￿calculated￿reference￿force￿and￿the￿damper￿characteristic￿map.
In￿the￿F12,￿the￿Dynamic￿Damper￿control￿is￿standard￿and￿the￿optional￿Active￿Roll￿Stabilization￿(ARS,￿SA
229),￿is￿available￿as￿an￿option.
6.4.￿Active￿Roll￿Stabilization￿ARS￿(Dynamic￿Drive)
The￿Active￿Roll￿Stabilization￿ARS￿was￿introduced￿for￿the￿first￿time￿in￿the￿E65/E66.￿With￿the￿F12,￿this￿is
available￿as￿option.￿(SA￿229)
ARS￿can￿bring￿about￿a￿noticeable￿reduction￿in￿the￿lateral￿tilt￿of￿the￿body￿that￿occurs￿during￿fast￿corner-
ing￿or￿avoidance￿maneuvers.￿During￿this￿process,￿the￿ARS￿reduces￿the￿required￿steering￿angle￿and￿al-
so￿minimizes￿the￿unwanted￿interference￿created￿by￿the￿wheels￿on￿the￿axle.
The￿ARS￿significantly￿improves￿the￿bump￿steer￿as￿well￿as￿the￿load￿change￿response￿of￿the￿vehicle.
Explanation
VDM￿control￿unit
Drive￿dynamic￿control￿switch
ICM￿control￿unit
EDC￿satellite,￿front￿left
EDC￿control￿valve￿for￿compression￿stage
EDC￿control￿valve￿for￿rebound
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