| 摘要 |
PURPOSE:To secure controllability and safety by performing steering control over rear wheels on the basis of a formula eliminating a specific term out of a specific formula when a specified driving state is detected, at the time of steering the rear wheels in accordance with a target steering angle being operated on the basis of the specific formula. CONSTITUTION:When a front-wheel steering angle being detected by a front- wheel steering angle sensor 35 is set to thetaF, a car speed being detected by a car speed sensor 31 to V, a yaw rate being detected by lateral G sensors 33, 34 to psi, and factors dependent upon a vehicle characteristic to KF and KR, respectively, each target steering angle TGthetaR of rear wheels is calculated on the basis of a numerical formula of TGthetaR=-KF.thetaF+KR.V.psi at a control unit. Then a servomotor 20 is controlled on the basis of this target steering angle TGthetaR. In suchlike rear-wheel steering system, at the time of detecting a specified state, for example, a wheel's sudden speed adjusted state (or a low speed state), steering control over the rear wheels is made so as to be performed on the basis of such a numerical formula as eliminating a first item (or a second item) out of the numerical formula. |
