The present study investigates potential risk factors which cause intersection accidents involving two vehicles crossing paths where visibility is good. In Japan these accidents occur frequently around rice fields. General consideration shows that a potentially colliding vehicle appears not to move but remains in the same relative position in the other driver's visual field. Such a vehicle may be difficult to detect, considering that the human peripheral vision's function is mainly to detect moving objects. We conducted indoor experiments using video clips to study the ability to detect a vehicle which may collide at an intersection. We found that the potentially colliding vehicle is difficult to find and can be detected only when it comes very close to the intersection. In contrast, a vehicle which moves in the visual field can be detected easily at some distance from the intersection. These findings show that the human visual search system has inherent characteristics which can be fundamental risk factors for intersection accidents. (A)
Abstract