X Series E70 X5 4.8i (N62TU) OFFRD
> Vertical Dynamic Management
The Vertical Dynamic Management offers the following advantages:
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Increased driving comfort
•
Increased vehicle agility
•
Improved independent steering performance and response to changing loads
The VDM increases driving comfort. Increased driving comfort is attained when the vertical movement of the
vehicle body is reduced to the minimum: whether this is due to agitation of the vehicle by the road surface
(unevenness, joints) or on curves.
The VDM controls the damper satellites in the actuation of the shock absorbers (impact force for individual
wheel). To this end, the VDM control unit is connected with the damper satellites via the very high speed
FlexRay databus. With a data transfer rate of 10 Mbit/s, FlexRay is significantly faster than the databuses
employed on comparable vehicles (in the areas of body and powertrain/suspension).
In addition to the higher bandwidth, FlexRay supports a realtime datatime transmission. FlexRay can be
configured to be error-tolerant.
The damper satellites (= control units) electronically regulate the impact forces.
The damper satellites and the EDC valves are directly connected to the shock absorbers. Each damper satellite
contains its own vertical acceleration sensor.
[more...]
> Active Roll Stabilisation (Marketing designation Dynamic Drive)
Dynamic Drive provides active stabilisers on the front and rear axles. These active stabilisers support continuous
adaptation to the current driving situation.
There is thus no necessity to make compromises between the basic attunement of the chassis to sporty or
comfortable driving. When you are driving straight ahead Dynamic Drive is "sensitively" activated, thus offering
the greatest possible degree of suspension comfort. Depending on the lateral acceleration, the lateral inclination
when taking cures or avoiding obstacles will be minimised by a "sporty" setting of the stabilisers. The active
stabilisers are vertically distributed in the centre. The active stabiliser consists of the oscillating motor and the
stabiliser halves mounted on the oscillating motor.
As one stabiliser half is connected with the shaft and the other with the housing, the stabiliser halves counter-
rotate. The torque thus produced exerts a stabilising effect on the rolling motion. The maximum system pressure
is 180 bar.
The most important control variable is the lateral acceleration. In addition the following signals are evaluated on
the PT-CAN:
•
Lateral acceleration
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Yaw rate
•
Vehicle road speed
•
Steering wheel angle
[more ...]
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Electronic height control (simple level control)
Ride height is controlled by air being fed into or withdrawn from the air springs. The EHC control unit receives
information about the ride height on the left and right-hand sides of the vehicle from the level sensors.
If the ride height is outside defined tolerances, the system will automatically activate the air supply unit to
regulate to the specified level.
The system is activated and starts to regulate whenever a door or the tailgate is opened. The system is
deactivated after a certain time (approx. 20 minutes).
SBT Electrical systems E70, E71
BMW AG - TIS
09.02.2013 00:58
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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