| 摘要 |
PURPOSE:To properly steer the rear wheels of a four-wheel steering car, in which the rear wheels are steered in control according to the yawrate, even though the axis of a yawrate sensor inclines. CONSTITUTION:A car speed sensor 31, front wheel steering angle sensor 32, yawrate sensor 34, and inclining angle sensor 35 sense, respectively, the car speed V, front wheel steering angle deltaf, yawrate gamma, and the inclining angle thetafore and aft of the axis of the yawrate sensor 34. a microcomputer 37 decides the yawrate proportion factor K1 and steering angle proportion factor K2 varying in accordance with the car speed V, decides the target steering angle deltar*=K1.gamma+K2.deltaf, and steers the rear wheels under control to the target angle of steering deltar*. When the inclining angle theta exhibits forward inclination (or backward) of the axis of the yawrate sensor 34, a correction is made so that the yawrate gamma or yawrate proportion factor K1 lessens (or enlarges) so as to cancel the influence of the roll rate upon the steering of the rear wheels in the condition that the axis of the yawrate sensor 34 is in inclination. It may also be acceptable that the amount of steering the rear wheels is limited by the angle of inclining theta. |
