| 摘要 |
PURPOSE:To prevent degradation of turning performance or oversensitive behavior of vehicle while achieving a desired steering characteristic by detecting switching of steering ratio characteristic and switching a transmission ratio characteristic. CONSTITUTION:Stepping motors 22, 64 in a steering ratio varying mechanism 4 and a transmission ratio varying mechanism 5 are controlled by a control means 6 which receives a steering angle signal theta11 from a steering angle sensor 67, a vehicle speed signal V from a vehicle speed sensor 68, a selection signal of steering ratio characteristics A, B from a control characteristic selection switch 69 and rotary angle signals from rotary angle sensors 54, 80. When the steering ratio characteristic A is selected, front wheel steering angle thetaF increases for same steering angle thetaH. Consequently, the transmission ratio decreases even under low speed and the front wheel steering angle thetaF increases, thereby sharp turn performance of vehicle is not impaired but improved under high speed operation because of decreased transmission ratio. |
