| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate degradation in the steering feeling and the effect on the behavior of a vehicle even when the steering characteristic is changed at high vehicle speed range by setting a plurality of control modes so that the different target current signal characteristic corresponding to the steering torque signal to be detected by a steering torque sensor is substantially same in the high vehicle speed range. SOLUTION: A mode X generating means 22 obtains a large auxiliary steering force by the steering operation with the small steering force, a mode Y generating means 22 corresponds to the steering in the normal mode, and a mode Z generating means 24 corresponds to the steering of the support mode. In the low vehicle speed range, the reaction of the road surface is small as the vehicle speed is increased, and the steering force is the smallest in the mode X, followed by Y and Z in this order. In the medium vehicle speed range, the steering force is small in the order of the modes X, Y and Z, and the absolute value of the smallness is reduced compared with that in the low vehicle speed range by the vehicle speed responsive braking. In the high vehicle speed range, the steering force is substantially same in the modes X, Y and Z by the large vehicle speed responsive breaking. The steering can be achieved at the favorite steering characteristic of a driver.</p> |
