Patent ID: 7668638

Claim:
An inter-vehicle distance control apparatus, comprising: a unit for controlling an inter-vehicle distance between a present vehicle equipped with this apparatus and a preceding vehicle traveling ahead of the present vehicle by controlling operations of the present vehicle, the unit being configured to change a deceleration gradient with which the deceleration of the present vehicle reaches a target deceleration between when the present vehicle is under a first deceleration condition in which the present vehicle decelerates under the circumstance where the inter-vehicle distance between the present vehicle and the preceding vehicle is relatively short and when the present vehicle is under a second deceleration condition in which the present vehicle decelerates under a circumstance where the inter-vehicle distance between the present vehicle and the preceding vehicle is relatively long, the deceleration gradient is determined based on a final fractional deviation of an inter-vehicle time period and a relative speed between the present vehicle and the preceding vehicle, wherein the final fractional deviation of the inter-vehicle time period is obtained by adding a shift amount of a fractional deviation to an original fractional deviation of the inter-vehicle time period, wherein the original fractional deviation of the inter-vehicle time period is obtained by subtracting a target inter-vehicle time period selected by the driver of the present vehicle from an actual inter-vehicle time period obtained by dividing an actual inter-vehicle distance between the present vehicle and the preceding vehicle by an actual vehicle speed of the present vehicle and then dividing the result of the subtraction by the target inter-vehicle time period, and wherein the shift amount of a fractional deviation is determined depending on the target inter-vehicle time period.