Research On Collision Compatibility Of A Car Based On Euro-NCAP MPDB Of 2020 Edition

Road traffic accidents are an important cause of human death.After the rapid development of vehicle safety in recent years,the crashworthiness of vehicles has made great progress,but it also objectively results in the increasing differentiation of the front structure design of vehicles.Crash incompatibleness is what researchers call the apparent difference in occupant injuries between vehicles in the crash statistics,and it’s becoming more pronounced in the crash statistics.How to improve the collision compatibility of vehicles on the premise of ensuring the crashworthiness of vehicles has become one of the important issues in vehicle safety research.In the MPDB test procedures released by Euro-NCAP in 2018,compatibility evaluation was introduced into the test evaluation procedures for the first time,which,to some extent,guided the future research direction of vehicle safety.In China,there are many references to Euro-NCAP when formulating regulations and test procedures related to vehicle safety.Therefore,the MPDB test procedures based on Euro-NCAP are very necessary for the study of vehicle collision compatibility.In this paper,based on the MPDB test procedure proposed by Euro-NCAP,the simulation test of Accord sedan was carried out,the crashworthiness and compatibility of the vehicle were measured and evaluated,and the specific measures to improve the compatibility of the vehicle were summarized.On the one hand,the width of the bumper beam in the vertical direction was increased.In test one,the width of the bumper was increased by 5mm,and in test two,the width of the bumper was increased by 10mm.On the other hand,the key structure of the front of the vehicle is adjusted for stiffness,so the thickness of the upper longitudinal beam and water tank frame and other structural parts is increased in the third test.Based on the analysis of the test results,it is concluded that increasing the bumper width is helpful to increase the coupling area between the vehicle and the barrier surface,improve the deformation uniformity of the barrier,reduce the SD of the barrier deformation standard deviation,and improve the compatibility evaluation level.Compared with test one,the SD value of the deformation uniformity index of barrier surface in test two increased rather than decreased,making the compatibility evaluation worse.That is to say,there is a certain limit to improve the collision compatibility of vehicles by increasing the width of the bumper,and the increase of the bumper width should be appropriate.The results of Test 3 show that increasing the stiffness of the key structure of the front part of the vehicle is helpful to solve the problem of excessive local stiffness,so that the front part of the vehicle forms a buffer absorbing area with uniform stiffness and the deformation of the barrier surface is uniform.On the other hand,multiple effective load transfer paths can be formed after the stiffness is moderately increased,and the energy absorption is more reasonable.In Experiment 4,the vehicle was comprehensively improved from the width and structural stiffness of the bumper,and the results of the improved vehicle simulation test were studied.It was found that the intrusion amount of each part of the vehicle increased slightly,and the damage measurement value of the dummy also increased partly,but on the whole it was far less than the corresponding damage threshold,ensuring sufficient crashworthiness.In the compatibility evaluation,the virtual occupant load OLC value has little change,the barrier deformation uniformity index SD value is greatly reduced,the barrier deformation uniformity is greatly improved,the overall penalty points are reduced,and the vehicle compatibility is significantly improved.