Research On The Impact Of AEB System On Pedestrian Injury In Human-Vehicle Accident Scenes

Pedestrians are vulnerable users of road traffic,and have a high rate of injury and death in traffic accidents.It is show that the death rate of pedestrians in road traffic accidents is as high as 25% in China.So,pedestrian protection has always been the focus of road safety..With the development of active safety technology,the protection of pedestrians is no longer limited to the passive safety level.The AEB system can protect pedestrians,but it has different protection effect in different traffic environment.Therefore,this paper studies the impact of AEB key parameter design on pedestrian injury in the scene of a pedestrian-vehicle collision scenario.The focus is on the situation where collisions cannot be avoided after loading the AEB system,and the rules and movement patterns of pedestrians after collisions in different postures.The conclusions can provide a theoretical basis for vehicle passive safety design and pedestrian protection,provide a reference for designing a pedestrian AEB system suitable for the road traffic in my country,and improve the effect of pedestrian protection as to better protect pedestrians.First of all,this paper screened out 437 cases of pedestrian-vehicle collision accidents from the NAIS databases,conducted statistics on the distribution of pedestrian-vehicle collision accidents,selected parameters that could reflect the characteristics of the accident.Then,using hierarchical cluster analysis,combined with the analysis of the proportion of different fields in each type of accident and the severity of pedestrian injury,the typical features of the scene are extracted,and finally five types of pedestrian and vehicle collision accident scenes that meet the typical road traffic in my country are obtained.Secondly,by using PC-Crash on real pedestrian-vehicle collision accident cases,the validity of the model and the practicability of PC-Crash in accident reconstruction are verified.Then,five typical accident cases are reconstructed and analyzed to get the relative position and motion parameters of vehicle and pedestrian 5 seconds before the collision,and AEB model is built in PC-Crash.And the orthogonal test method is used to design the key parameters of AEB,analyze the rules of pedestrian damage in different scenarios and verify the effectiveness of the AEB model.Ultimately the sensitive factors of AEB design parameters in the unsuccessful collision avoidance scenario are obtained,,which provided a reference for the design of pedestrian AEB in different scenarios.Finally,the four types of scenes in which collision could not be avoided was selected with the key parameter combination of AEB with the greatest influence on pedestrian HIC value,and studied the impact of different pedestrian states and heights and weights on pedestrian injuries.It is concluded that different pedestrian posture and height have great influence on pedestrian injury in each kind of scenes,but the different steering angles and weights have little effect on pedestrian injuries;AEB can reduce the impact speed,which will affect the movement of the collision position in the process of vehicle and pedestrian collision.Although it can’t completely avoid the collision,it can greatly reduce the pedestrian injury.