| 摘要 |
PROBLEM TO BE SOLVED: To estimate a possibility of rear-end collision without using any detection means such as a radar for detecting a succeeding vehicle, to optimize the size of the back set between an occupant's head and a headrest in accordance with the estimated result.SOLUTION: A position of a vehicle is detected. If the detected position of the vehicle is within a range, shown by information stored in storage means where information showing the range with a possibility that the succeeding vehicle may collide with the vehicle from the rear side is stored in advance, the positional movement of a front portion 12b of the headrest is controlled so that the back set, as a horizontal distance between the head of the passenger A and the front portion 12b of the headrest, is smaller than the back set in the time when the vehicle position is out of the range (S114). |
