| 摘要 |
PURPOSE:To detect an abnormality of a front wheel steering angle sensor and convert to the 2WS smoothly with a simple composition, by deciding that the front wheel steering angle sensor is abnormal when the steering angle variation amount in the front wheel steering system exceeds a preset value, and putting back the rear wheels to the neutral steering position. CONSTITUTION:While the front wheels 1 are steered by a handle 2 through a front side power steering unit 3, the rear wheels 4 are steered by a servomotor 5 through a rear side power steering unit 6, and the servomotor 5 is controlled by a motor driving device 7. And a control unit 11 computes the rear wheel steering angle ratio to the front wheel steering angle responding to the car speed, depending on the signals from various sensors 12 and 13, and inputs the resultant signal to the motor driving device 7. In this case, when the steering angle variation amount in the front wheel steering system exceeds the preset value, the control unit 11 decides that the steering angle sensor 13 of the front wheels is abnormal. In such an abnormal condition, the rear wheel steering angle is kept at zero and the steering is converted to the ordinary 2WS. |
