VDM: Vertical Dynamics Management

The VDM control unit is located in the passenger footwell at the A-pillar.

Fig 1: Identifying Vertical Dynamics Management Control Unit

Courtesy of BMW OF NORTH AMERICA, INC.

Item	Explanation
1	A-pillar trim
2	Vertical Dynamics Management control unit
3	47-pin plug connection

The VDM enhances on-road comfort. Greater on-road comfort is achieved when the vehicle body moves vertically as little as possible: whether this is due to agitation of the vehicle by the roadway surface (unevenness, joints) or on curves. The VDM controls the damper satellites in the activation of the shock absorbers (impact force for individual wheel). To this end, the VDM control unit is connected to the damper satellites via the very fast FlexRay data bus.

With a data transfer rate of 10 MBit/s, FlexRay is significantly faster than the data buses deployed nowadays in motor vehicles (in the area of body and drive or chassis). FlexRay supports not only the greater bandwidth but also data interchange with real-time capability. FlexRay can be configured as error-tolerant.