Method for estimating position of objective obstacle for vehicle 

In a vehicle equipped with a distance measuring unit capable of measuring a distance between the subject vehicle and an objective obstacle, the objective obstacle is detected along a widthwise direction of the vehicle by the distance measuring unit. Detection data detected by the distance measuring unit are developed on X and Y coordinates in which the widthwise direction of the subject vehicle is represented by an X axis; the longitudinal direction of the subject vehicle is represented by a Y axis, and the position of the subject vehicle is defined as an origin. Each of obstacle data is labeled in such a manner that the same labels are affixed to obstacle data which are in proximity to one another on the coordinates. The amount and direction of movement are calculated for every label on the basis of the last data and the current data, and a relative speed for every label relative to the subject vehicle is calculated by dividing the amount of movement by a sampling time. The position of the objective obstacle after a lapse of a predetermined time is estimated on the basis of a relative speed vector determined from the relative speed and the direction of movement. Thus, the accuracy of estimating of the position of the objective obstacle is improved.