Abstract
Keywords: Traffic safety, Accident, Active safety, Drive recorder, Driving behavior, Traffic circumstance, Driving simulator
In order to analyze the incident mechanism of traffic accident, over 700 "Forward Collision Near-Miss Incident" data are classified into 8 types by the factors of road environment and vehicle behavior. As typical example, we analyze the focusing incident data in vehicle following situation. We focus the relationship between the time headway and the braking reaction time of driver in the situation. The time headway is defined as the relative distance to a forward vehicle divided by the vehicle velocity. The incident data in vehicle following situation has the features that the time headway is shorter and the reaction time is longer than the usual braking in vehicle following situation. The data was obtained in Tokyo metropolitan area. An example of incident in pre-crash moment in vehicle following situation is shown as follows. CarA was following the forward CarB in the state where CarC run in the adjacent traffic lane. CarA was going to approach the forward vehicle (CarB) even though there was slowdown action of the CarB when CarC was accelerating smoothly in the adjacent lane. This example of incident shows the traffic circumstance strongly influenced the driver behavior. Moreover, from the experiments of the same circumstance using driving simulator, it also shows the trend that the behavior of the vehicle in the adjacent lane affects the driving behavior as they might reduce situation awareness to the forward vehicle, resulting the shorter time headway.