Study On The Effect Of The Neck Muscle Active Force On The Pedestrian Brain Injury In Pedestrian Vehicle Accidents

The head is the main site of human body injury in the collision accidents of pedestrian and vehicle,which often leads to pedestrian death or loss of some abilities,and is accompanied by serious sequelae.In pedestrian accidents,the study of head injury is of great significance to pedestrian protection.However,in previous studies,there were few studies on the effects of neck restraint and active muscle force on the injury and injury mechanism of pedestrian head.In addition,the current design of the new vehicle is evaluated for pedestrian head protection by using a head impactor test system,these effects are not considered in the new car assessment program(NCAP)nor are these issues noticed in the vehicle safety laws.The research carried out in this paper aims to study the effect of the active force of the neck muscle on the brain injury in pedestrian accidents by usi ng real pedestrian-vehicle accident cases and using the method of accident reconstruction and injury reconstruction.In the process of the study,this paper first carried out accident reconstruction and injury reconstruction based on a real pedestrian-vehicle collision accident.Based on this,a method for the analysis and research of this paper was established,and the effect of the neck muscle active force on the pedestrian brain injury was preliminarily explored.Then the method is used to carry out the analysis and study of multiple accident cases,and the related parameters of brain in reconstruction are calculated.Finally,the differences of brain correlation parameters in active and passive simulation results were compared and analyzed.Logistic regr ession analysis was used to create the AIS3+ risk curve of brain injury.The difference of the injury risk curves in the results of active and passive models under different brain injury parameters was further analyzed.The results showed that the activation of the neck muscles indeed affect the rotational motion of the head,which changed the collision direction and posture of the head,and resulted in the different distribution of the physical parameters of the brain injury in the active and passive models.Comparing the calculated results of the head injury criterion HIC,pedestrian head collision velocity and collision angle,it can be seen that the simulation results of active and passive models are close to the accident reconstruction results.In the same accident,the result of the active model is closer to the corresponding value of the accident reconstruction.By comparing the AIS3+ risk curves of different brain injury parameters of active and passive models,it can be found that the risk curves of active and passive models have significant differences under the same brain injury parameters.The brain injury p arameters of the active model are less than those of the passive model to some extent when the probability of AIS3+ injury is 50%.It is concluded that under the same collision conditions,the active force of the neck muscles in pedestrian accidents can affect the kinematics response of the head and reduce the risk of head injury.