| 摘要 |
PURPOSE:To provide a sufficient turning-round characteristic by providing a construction in which, at the time of rapid turn, an instantaneous antiphase steer angle is set with respect to a rear wheel, and causing this instantaneous antiphase steer angle when a lateral acceleration is high to be increased correspondingly. CONSTITUTION:A controller 9 is connected thereto with a handle angle sensor 10, a vehicle speed sensor 11, and a power steering pressure sensor 12. A road surface muis estimated in a road surface mu estimation section 9A on the basis of the information obtained from those sensors, and a lateral acceleration (lateral G) is calculated in a lateral G calculation section 9B on the basis of that mu value, the steering wheel angle QH determined by the power steer pressure sensor 12, and a vehicle speed V. The rear-wheel steering device further comprises an instantaneous antiphase steer angle setting means G for subjecting a rear wheel to an instantaneous antiphase control on the basis of the vehicle speed V at the time when the vehicle is rapidly turned, and a correction means 9F for increasing the instantaneous steer angle, for correction, when the lateral acceleration G is great. Accordingly, even when the vehicle turning- round characteristic using front wheels is lowered at the time of large lateral G, it is possible to enhance the turning-round characteristic through increase in the instantaneous antiphase steer angle. |
