| 摘要 |
PURPOSE:To enhance the steering stability by causing a control effect combined with an F/B control to be sufficiently exhibited with use of 4WS based on F/F control and F/B control even in a region of high-speed and large steer-angle. CONSTITUTION:F/F control sections 5, 6 are each so constructed as to calculate a target steer angle deltagammamFF by using a linear target yaw rate (d/dt) phigammaFF and a linear vehicle model. A calculation section 11 for a target yaw rate value (d/dt) phigammaFB based on the use of F/B control is set with respect to the F/B control section, separately. In a case where the calculation section 11 sets, for example, a stationary target characteristic and an excessive target characteristic, estimation is made of a yaw rate which stationarily generates in response to a change in vehicle wheel corner ring power in corresponding relation to the side-slip angle of the vehicle wheel, in regard to a stationary target yaw rate characteristic thereof, this estimated yaw rate being set as a stationary value for the F/B control target yaw rate. Even at the time of high-speed and large steer-angle when the side-slip angle of the vehicle wheel is large, coincidence of the generated yaw rate with an F/B control target yaw rate is just achieved and a control steer angle input resulting from F/B control is prevented from becoming excessively large, by which the F/B control effectively acts on an external disturbance input and the like as its original inhibition object. |
