| 摘要 |
PURPOSE:To ensure turning-around ability at the initial stage of cornering of a vehicle and safety of a vehicle during steady cornering with high response in a manner to make the two properties compatible with each other. CONSTITUTION:A front wheel steering mechanism A is provided with a servo motor 21, and steering of front wheels 1 is effected by means of the rotation force of the motor 21. The steering angle of a handle 8 is detected by means of a sensor 23. A yaw speed (PSI speed) is detected by means of lateral G sensors 25 and 26. A control rule for front wheel steering is defined by formulas of TGthetaF=K3XthetaH+K4XPSI speed K3>1.0 and K4<0, wherein TGthetaF is a target front wheel steering angle and thetaH is a demand front wheel steering angle decided by a handle steering angle. According to the control rule, during the initial stage of cornering where steering of a handle is started, i.e., until a yaw speed is generated, front wheels are steered in a direction in which steering of the handle is further turned. Thereafter, along with the generation of the yaw speed, the second item of the control rule starts to have a negative value, whereby control of the front wheels is effected in a direction in which the handle is turned back. |
