PURPOSE: To improve the stability of a vehicle by controlling the brake power distribution for the front and rear wheels so that the brake power increases on the front wheel side, when it is judged that the vehicle is in an unstable state and the yawing moment in the direction in which the vehicle leteral move ment state is stabilized by the front wheel lateral force is not generated.
CONSTITUTION: The output signals of a stepping force sensor 11, optical speed sensor 13 for detecting the speed in the longitudinal and lateral directions of a vehicle, steering angle sensor 15, front wheel lateral acceleration speed sensor 16, etc., are inputted into a controller 9. The stability of the vehicle is judged accoring to the lateral movement state, and when it is judged that the vehicle is in an unstable state, the yawing moment of the vehicle is controlled by reducing the lateral force of the front wheel. In this control, only in the case where the yawing moment in the direction in which the leteral movement of the vehicle is stabilized according to the generation direction of the actual lateral acceleration speed generated by the atcual front wheel lateral force is not generated, the brake power distribution of the front and rear wheels is controlled so that the brake power increases on the front wheel side, and the lateral force of the front wheel is reduced, and the vehicle is stabilized.
YAMAGUCHI HIROTSUGU
INOUE HIDEAKI
