CONTROL OF REAR WHEEL STEERING GEAR

摘要

PURPOSE:To cooperatively keep a vehicle to the stable side under the small behavior condition always in the control of ABS or the like by judging whether or not a control signal of the ABS control or the like is inputted to change over the inputted control signal to a proportional gain as a steering wheel angle factor gradually reducing as time goes on. CONSTITUTION:While the same phase side yaw rate factor Kgamma is gradually reduced as the vehicle speed V is reduced in the reduction of vehicle speed by ABS control, the inverse phase side temporary proportional gain Ktheta' is a function of time and reduces more largely than the yaw rate factor Kgamma. A desired rear wheel steering angle ET is calculated from a value Ktheta'.theta of the steering wheel angle theta multiplied by temporary proportional gain Ktheta' and a value Kgamma.gamma of the yaw rate gamma multiplied by the yaw rate factor Kgamma to control the rear wheel steering. Thus, even if a driver turns the wheel provisionally on a slippery road surface the value of Ktheta'.theta will have very small effect leaving only the value of Kgamma.gamma so that the rear wheels 11 are steered to keep the vehicle to the stable side under the condition of small change of behavior.