X6-DPC-Road&Track Article

[Palbay]

Found this article by Dennis Simanaitis at Road and Track.com.I only posted the section on DPC.The entire article can be found at the link below.Anyone who has pushed an X6 in the twisty stuff can relate to the info in this article.Just don't lift in the curve.....DPC will whisk you right around the corner! Thanks! PalBay BMW X6: Dynamic Performance Control
The BMW X6's Dynamic Performance Control, the newest of our collection, needs to be described within the context of the car's other stability- and traction-enhancing devices, all functioning interactively. Briefly, DPC (BMW dislikes this initialism; we use it, with apologies, as an ink-saver) is an active splitting of torque at the rear of the X6's all-wheel drive. Its innovative rear differential contains two added planetary gearsets and clutch packs under computer control. DPC is unique in that its lateral interventions are subtle and at less than extreme levels of vehicle behavior.

Diverting torque from one side to the other has a similar dynamic result as subtle braking of the one side, with no diminishment of progress. The intent of these interventions is to enhance directional precision and agility of the X6 at any speed, not just at the limit.

Other more familiar aspects of the X6's Integrated Chassis Management include BMW Dynamic Stability Control, Dynamic Traction Control, xDrive all-wheel drive and, if fitted, optional Active Steering. DSC and DTC use conventional strategies of torque reduction and selective braking to enhance the car's stability and progress at the extremes of its performance envelope. Inputs are received from sensors of lateral g, yaw rate, steering angle and ABS operation. Reflecting the X6's higher center of gravity, there's an additional sensor monitoring the roll rate of the vehicle.

There are selectable modes, the first disconnecting DTC (for rocking out of a snow rut, as an example), the second disengaging both it and DSC. Once disconnected, they stay so. By contrast, DPC is always on — in a sense, operating in the background of even routine vehicle operation.

Active Steering is an X6 option that incorporates an auxiliary planetary gearset to achieve real-time ratio variability of the steering. (Note: This is variable ratio; not simply variable assist.) If fitted, Active Steering gets used as an initial control strategy; this, because steering provides a quicker response than selective braking or changes in torque. Its changes of ratio are capable of giving slight steering corrections.

Elsewhere in this issue is our Road Test of the BMW X6. Detroit Editor Shaun Bailey adds insights here: The X6 feels secure, planted and predictable. In high-performance driving, purposely without DSC's safety net, Dynamic Performance Control and xDrive interact well enough that the driver can't tell they're working. It's just that the X6 goes through a corner faster and with less effort than expected.

http://www.roadandtrack.com/article....rticle_id=6826