Study On Small Overlap Crash

Along with the increase of car ownership, the auto safety has increasingly become a problem that people are concern about. When cars get into collision accidents, they mainly have front collision, side collision, rear-end collision, rollover and so on. Relevant data show that front crash is one of the most common collision accident of all forms, and small overlap front offset collision accounts for about a quarter of the death of head-on collision accidents. This article mainly aimed at the research of force transmission path, energy distribution and structure improvement of small overlap front offset collision to improve the overall safety performance of cars.First of all, the factors affecting the precision of finite element model simulation, a few aspects of small offset frontal crash such as the evaluation index were introduced. We took a SUV as a benchmark model, and used hyperworks software package to establish the finite element analysis model according to the small overlap front offset collision test specification of the Insurance Institute for Highway Safety (IIHS)* and then, set the vehicle collision conditions, and proceeded the 25% offset impact analysis, and used the small overlap front offset collision evaluation index to evaluate the result. Then use the same finite element model for 40% and 100% front offset impact collisions to analyze the body deformation under different working conditions of the collision, mainly compared from the force transmission path, the energy distribution and body deformation.Then analyzed the body structure and vehicle collision force transmission path in the process of collision from the perspective of improving collision force transmission path in order to improve the vehicle collision safety performance and the key parts for body structure design, and analysis results show that the improved structure has reduced the invasion amount of the crew compartment of each measurement point, the vehicle collision safety level has been improved from poor level to an acceptable level to a certain vehicle structure assessment.Finally, using optimization design method, selected the most important four parts which influence the result significantly of the collision force path as design object to improve the small overlap front collision safety performance under small overlap rate and to achieve the purpose of vehicle lightweight, mainly by considering the thickness of sheet metal material parameters and parts of reasonable matching. Optimization results show that with reasonable matching of the material parameters and thickness of the parts in front key structure, vehicle collision acceleration peak value had decreased, quantity of crew capsule invasion in each measurement point was greatly reduced, various performance indexes could meet the demands of engineering design, the overall effect is improved obviously, and at the same time realized the vehicle lightweight in the view of improving the performance of the vehicle collision safety.This paper takes the improvement of the small overlap collision security performance as a starting point, studied the vehicle crashworthiness performance in small overlap collision combining with the finite element simulation technology and optimization design method. Through the study of this article, the small overlap collision safety performance has been improved significantly and at the same time realized the vehicle lightweight. So, this method has certain engineering application value.