Brake Modulation for Increasing Agility

The highly advanced hardware of the DSC F0x enables brake modulation to be carried out without unpleasant feedback for the driver. On the F01/F02, that capability is utilized to influence the vehicle's self-steering characteristics is a specifically targeted way.

Index	Explanation
1	Course of an understeering vehicle
2	Course of a vehicle with neutral handling
3	Individual modulation of brakes to prevent understeer
4	Increased engine torque to compensate for braking force
M	Yaw force acting on the vehicle as a result of individual modulation of brakes

If the vehicle begins to understeer, e. g. when cornering quickly, the central dynamic handling controller on the ICM detects the very first indications that it is starting to happen. A required setting is transmitted to the DSC requiring it to apply the brake on the rear wheel on the inside of the bend. The DSC sensitively applies the required setting and without generating a level of noise perceptible by the driver. The uneven braking effect thus produced, creates a yaw force acting around the vehicle's center of gravity. As a result, the vehicle turns towards the inside of the bend, doesn't understeer and corners with absolutely neutral handling.

This type of brake modulation increases road safety because it prevents the vehicle drifting towards the outside of the bend. The disadvantage, however, is that the vehicle is slowed slightly by the application of the brake and thus a degree of momentum is lost.

Therefore, in typical BMW fashion, the solution is taken a step further. Whenever handling stability considerations allow, the engine torque is increased simultaneously with brake application. The higher engine torque is transmitted to the road by the wheel on the outside of the bend that is not being braked. The control strategy ensures that the increase exactly matches the retardation by the brake application.

While that DSC function is active, there is no display of any kind on the instrument cluster.

In that way, highly advanced components (DSC) and intelligent control strategies are combined to produce an overall effect that substantially improves agility without impairing the handling stability of the vehicle.