# Simulation of AEBS Applicability by Changing Radar Detection Angle
## 4 Applications of the AEBS to Actual Cases  
_Applications to Actual Cases_  
Figure 13 shows the result of applying the AEBS to an actual traffic accident case. Here, the upper figure shows the traffic accident that occurred without the AEBS, and the lower figure is the result predicted by simulation of how the outcome would have changed if the AEBS were applied to the actual accident. The accident outline identified through the ACCC is one where a collision occurred when a southeast-bound vehicle did not see a pedestrian walking from a pedestrian crossing during the night until it was too late, and the pedestrian was struck by a vehicle. The driving speed of the vehicle was 46.5 km/h, and the collision speed was 28.9 km/h. A grid pattern circled in the top figure indicated the collision point. If the AEBS was applied to this accident, as shown in the figure below, with the detection distance of 100 m and the detection angle of 4\({}^{\circ}\), the vehicle would have stopped completely before the collision point, so collision with the pedestrian would not occur. The accident outline depicted in Figure 14 is an example of an eastbound vehicle crashing at a signal intersection while speeding (driving speed of 91 km/h), and a vehicle with a westbound left turn due to a signal violation (collision speed of 37.8 km/h). In this case, as shown in the figure below, after applying the AEBS with a detection distance of 100 m and a detection angle of 4\({}^{\circ}\), it could be seen that the eastbound vehicle stopped safely before the collision point. Figure 14: Real Case 2 application of the AEBS. Figure 13: Real Case 1 application of the AEBS. The outline of the accident in Figure 15 is one where a vehicle waiting in a left-turn lane suddenly changes lanes and collides with a vehicle driving in a through lane. The driving speed of the vehicle was 55 km/h and a collision speed of 44.3 km/h. In this case, it was also found that no accident occurred when the AEBS, with a detection distance of 100 m and a detection angle of 10\({}^{\circ}\), was applied to the through vehicle. Figure 16 is an accident that occurred while the vehicle driving in the first lane turned into a left-turning pocket, and the vehicle driving in the second lane suddenly crossed both lanes into the left-turning pocket. First, the vehicle's driving speed was 30 km/h, and the collision speed was 29.7 km/h. In this case, even if the AEBS with a detection distance of 100 m and a detection angle of 10\({}^{\circ}\), which prevented accidents, were applied, the collision speed was only reduced by 0.1 km/h. In the end, it shows that the AEBS considered in this study is not effective in accidents caused by lane changes. In a sense, this is intuitive as the vehicle is equipped with forward collision avoidance sensors and not with blind spot detection sensors. However, even in this case, considering the positions of the front and rear vehicles over time, if the angle is large enough, it is a condition that can involve the AEBS. Therefore, this case was simulated and resulted in a near-avoidance of the radar detection range. Figure 16: Real Case 4 application of the AEBS. Figure 15: Real Case 3 application of the AEBS. Table 5 shows the total of 144 simulation results applying the AEBS to 30 actual accident cases considered in this study. First, traffic accident types were divided into four categories: intersection collision, pedestrian collision, rear-end collision, and lane change. After applying the AEBS to both accident vehicles in one traffic accident case, the simulation was performed by changing the radar angle to 4\({}^{\circ}\), 6\({}^{\circ}\), 8\({}^{\circ}\), and 10\({}^{\circ}\). In Table 5, \"N/A\" indicates that it is meaningless to apply the AEBS to a vehicle or pedestrian in front of a collision in a rear-end collision or pedestrian collision. In addition, \"SN\" is the serial number of the traffic accident case, and \"Vw/o\" is the speed at the time of the collision estimated in the actual accident without AEBS.