| 摘要 |
A stepwise brake control is automatically performed when TTC obtained according to a relative distance and a relative speed between a vehicle and an object is lower than a predetermined value. For example, a brake force or a brake reduction speed is gradually increased over a plurality of stages in time series. Moreover, a brake force or a brake reduction speed change ratio in the section from the rise point of a brake force or a brake reduction speed at each stage to a predetermined brake force or a brake reduction speed is made a predetermined value or a change process is made a change process along a curved shape defined by a predetermined function. Moreover, at the initial stage when gradually increasing the brake force or the brake reduction speed, an auxiliary brake is used. Alternatively, a caution stage having a brake force or a brake reduction speed smaller that the initial stage is provided at the stage preceding the first stage of the plurality of stages, so that the auxiliary brake is used at this caution stage. |
