| 摘要 |
PURPOSE:To make a driver recognize an abnormal condition of the rear wheels even though an alarm cannot be operated. CONSTITUTION:A microcomputer 35 controls to steer the left rear wheel RW1 and the right rear wheel RW2 to an object steering angle decided according to the car speed, the yaw rate, and the front wheel steering angle, detected by a car speed sensor 31, a yaw rate sensor 32, and a front wheel steering angle sensor 33. When an abnormal condition is generated to the steering control of the left and the right rear wheels RW1 and RW2, the steering angles of the left and the right rear wheels RW1 and RW2 are maintained while they are steered at a minute steering angle, provided that the parts of a rear wheel steering angle sensor 34 and an electric motor 21 are normal. Consequently, since the neutral position of a steering handle 11 in a straight running condition of the vehicle is slipped a little to the left or to the right from a mechanical neutral position (the neutral position of the steering handle 11 when the left and the right rear wheels RW1 and RW2 are maintained in the neutral condition), the driver can recognize the abnormal condition of the rear wheels. |
