Braking force control system for motor vehicle

A braking force control system for a motor vehicle, having a hydraulic pressure control device which controls a hydraulic pressure generated by a master cylinder or a pump in a braking system, so as to increase or decrease in accordance with a drive state of the motor vehicle, comprising:

• actual-slip-factor calculation means for calculating an actual slip factor of a wheel;
• target-braking-torque calculation means for calculating a target braking torque from a preset target slip factor and said calculated actual slip factor so that a wheel speed may come to afford the target slip factor;
• target-braking-hydraulic-pressure conversion means for converting said target braking torque into a target braking hydraulic pressure;
• detection means for detecting said hydraulic pressure generated by the master cylinder or the pump;
• estimative-braking-hydraulic-pressure calculation means for calculating an estimative braking hydraulic pressure which is estimated to be currently acting in the braking system, from said detected hydraulic pressure and a past value of said estimative braking hydraulic pressure by the use of a hydraulic pressure model;
• and
• controlled-variable calculation means for calculating a controlled variable of the hydraulic pressure control device from said calculated estimative braking hydraulic pressure and the target braking hydraulic pressure by the use of a reverse hydraulic pressure model.