Patent ID: 8150591
Filing Date: 2012-04-03
Classification: B60W

Abstract:
1. A vehicle speed control system comprising: a distance acquisition section for successively acquiring a curve entrance arrival distance, which is a distance from a subject vehicle to an entrance of a curving road existing ahead of the subject vehicle; a speed acquiring section for acquiring an actual speed of the subject vehicle; a curvature radius acquisition section for acquiring a radius of curvature of the curving road; a target speed setting section for setting a curve-time target speed, to which the subject vehicle is controlled in traveling the curving road, based on the radius of curvature of the curving road and a target lateral acceleration, which is a target for the subject vehicle to travel the curving road; a speed difference calculation section for calculating a difference between the curve-time target speed and the actual speed; an evaluation index calculation section for successively calculating a corrected approach/separation condition evaluation index, as an index indicating an approach/separation condition of the subject vehicle relative to the entrance of the curving road in correspondence to the curve-time target speed, based on a rate of time change of a seeming area of a forward object projected on a retina of a driver, the corrected evaluation index increasing as the speed difference increases and increasing at a greater rate as the curve entrance arrival distance decreases with respect to a same speed difference; a threshold checking section for checking whether the corrected approach/separation condition evaluation index calculated by the evaluation index calculation section exceeds a threshold value determined by a threshold calculation equation of the corrected approach/separation condition evaluation index; a memory section for storing a corrected target relative speed calculation equation, which corrects a target relative speed calculation equation so that a target relative speed at the entrance of the curving road becomes the curve-time target speed and a corrected target relative speed is calculated by multiplying a target relative speed calculated by the target relative speed calculation equation and a ratio of a difference between the speed of the subject vehicle at a time of starting control and the curve-time target speed relative to the speed of the subject vehicle at the time of starting control, the corrected target relative speed calculation equation being set by a target relative speed calculation section for calculating a corrected target relative speed based on the corrected target relative speed calculation equation stored in the memory section and the curve-entrance arrival distance actually acquired by the distance acquisition section, when the threshold check section determines that the corrected approach/separation condition evaluation index is determined to exceed the threshold value; a target deceleration calculation section for calculating a target deceleration based on a corrected target deceleration calculated by the target relative speed calculation section and the actual speed of the subject vehicle based on the speed acquisition section; and a control section for controlling the subject vehicle to attain the target deceleration.