Robert Boschgmbh

Mirko Trefzer

Thomas Sauter

Rainer Heinsohn

A method and an apparatus for regulating the speed of the low-&#x3bc; wheel as a vehicle starts from rest or accelerates on a road surface having adhesive friction values that differ between the left and right sides of the vehicle (split-&#x3bc;), the low-&#x3bc; wheel being braked by braking intervention when it has exceeded a defined slip threshold. In order to improve the acceleration behavior of the vehicle, it is proposed to regulate the speed of the slipping low-&#x3bc; wheel to a defined setpoint speed during a setpoint speed regulation phase in which the setpoint pressure for the brake of the low-&#x3bc; wheel is set so that the wheel tracks the setpoint speed; to discontinue setpoint speed regulation when the high-&#x3bc; wheel meets a defined breakaway condition; to initiate a setpoint pressure control operation during a setpoint pressure control phase in which the setpoint pressure of the low-&#x3bc; wheel is abruptly reduced in order to decrease the drive torque transferred to the high-&#x3bc; wheel; and lastly to continue setpoint speed regulation.

Rapid capture of a slipping high-mu wheel during a setpoint speed regulation operation

A method for providing traction control when starting off a vehicle on a road surface having different adhesive friction values between the right and left sides of the vehicle, the driven low-&mgr; wheel being regulated to a specified setpoint slip pre-control value by a braking intervention if spinning occurs. In order to improve driving comfort, the engine speed is adjusted to the particular standing start conditions. To this end, the engine torque actually required for starting off is determined as soon as the vehicle is set in motion and has exceeded a specified speed threshold, and the engine speed actually required for starting off under the given conditions is determined from this. From this in turn, a new, corrected setpoint slip value is calculated and the setpoint slip is abruptly reduced or increased from the setpoint slip pre-control value to the newly calculated, corrected setpoint slip value.

Growing community of inventors

Ettlingen, Germany

Mirko Trefzer