Uncertainty Analysis And Head Injury Study Of Electric Two-wheelers Accidents

Electric two-wheelers riders,as a vulnerable group of road users,are extremely vulnerable to collisions with cars.In recent years,the development of China's automobile safety technology and new vehicle evaluation procedures has played a positive role in road traffic safety.Electric two-wheelers(ETWs)accident still occurs frequently,and have occupied the main part of non-motor vehicle accidents.In order to assist the judiciary in clarifying the responsibility of such accidents,and to protect the legitimate rights and interests of the disadvantaged group of riders,it is necessary to investigate and analyze such accidents.The reconstruction of accidents refers to the use of valuable information such as traces of accident scenes to restore the whole process of accidents.It is an important way to study the work of car passive safety,accident liability identification,and car insurance claims.Domestic and foreign scholars have widely used this method to study traffic accidents.However,the traditional traffic accident reproduction does not consider the existence of the uncertainty factor at the accident site.The result of the reproduction(the velocity of the car,the head injury of the rider)is often too high or too low,and the reconstruction is only obtained by inputting specific parameters.The result is not scientific as an accident liability determination.Therefore,the uncertainty method is introduced into this field,and the probability distribution and frequency distribution of the accident reconstruction result could be obtained,so that the reproduction result is more objective and reliable.It is of great practical significance to provide objective and credible reproduction results for actual traffic accidents.Domestic and foreign scholars' research on two-wheeler accidents mainly focuses on bicycles and motorcycles,but there are few studies on ETWs accidents.The research on the uncertainty of input parameters in the process of accident reconstruction is not high.The multi-factor input parameters,the reproduction results obtained by a single determined input parameter lack objectivity and reliability.In order to fully and reasonably use the accident information at the accident site,based on the reconstruction of accidents involving cars and ETWs,the uncertainty analysis of the reproduction results is made to make the reconstruction results more reasonable and persuasive in this paper,the accidents of car and ETWs with detailed video information are reproduced.The video analysis method(direct linear transformation or frame-by-framc analysis)is used to estimate the velocity of the vehicle in the accident videos,and then use PC-Crash,MADYMO.The multi-body software reproduces the vehicle velocity and the cyclist's kinematics,and obtains more accurate collision velocity and the injury parameters of the rider's head.At the same time,the uncertainty analysis of the car velocity is carried out,and the objective vehicle velocity reproduction result is obtained.On this basis,the uncertainty analysis of the rider's head injury is carried out.In order to better introduce the uncertainty parameters in the accidents of cars and ETWs into the accident reconstruction results,and obtain objective and reasonable convincing accident reproduction results,this paper uses Latin Hypercube experimental design and PC-Crash to simulate in the experiment,the response surface model is obtained by the response surface method,and the probability distribution of the accident reproduction result is obtained by the Monte Carlo method.Finally,three accident cases of car and ETWs were selected.The response surface Monte Carlo method was used to analyze the uncertainty of the accident velocity of the car and the head injury of the rider.It is found that the results of vehicle velocity uncertainty analysis are basically consistent with the results obtained from accurate accident reconstruction.The head injury level of riders are highly consistent with the forensic identification of brain injury records.This method could be used to evaluate the level of head injury of riders in ETWs accidents,and provides a theoretical basis and empirical method for the study of head injury of the riders.