Patent ID: 7762633

Claim:
A brake control system for a motor vehicle having a plurality of wheels, a plurality of brakes, each brake being associated with a respective wheel, and a gradient sensor to determine the slope of the ground upon which the vehicle stands, the system comprising: a driver operated brake command input; a brake actuator for actuating at least one of the plurality of brakes; and a brake controller for controlling the brake actuator in accordance with the operation of the brake command input and vehicle parameters, the brake controller arranged to detect that the vehicle is held stationary while facing forwardly in a downward direction on a descending slope by a braking effort supplied by the brakes in accordance with the operation of the brake command input; and a driver interface for activating a hill descent control mode with a preset vehicle speed, the hill descent control mode preventing the vehicle from traveling the descending slope at a speed greater than the preset vehicle speed; wherein upon activation of the hill descent control mode and operation of the brake command input to release the brakes while the vehicle is facing forwardly in the downward direction and held stationary on the descending slope, the brake controller gradually decreases the braking effort over time as a function of the steepness of the descending slope to allow the vehicle to accelerate more slowly than the vehicle would accelerate under gravity until the preset vehicle speed is reached and then controls the brake actuator to automatically apply the brakes as needed to prevent the vehicle from traveling the descending slope at a speed greater than the preset vehicle speed.