Research On Structure Optimization Of Vehicle Offset Impact Safety Based On Crashworthiness And Simulation

With the increasing number of vehicle ownership, more and more accidents happen around us, vehicle safety has attracted great attention. Traffic accident has become a worldwide society problem. During the motorcar accidents, front crash takes the majority part, which amounts about forty percent. And the offset front crash is the largest part among the front accident. So the research on offset front crashworthiness of vehicle is one of important aspect in vehicle safety research.At present, every major vehicle manufacturing countries have constituted strict crash safety rule of law and request vehicle manufacturing and developing should allow strict standard. The new car assessment program (NCAP) was introduced into China in year 2006, which was combined with Chinese own traffic situation to form C-NCAP system. This is the first offset crash test standard in China. As our country has dropped behind to high-level international crashworthiness research and the ability of independence developing and research is not strong, we need to strengthen the research and application of vehicle’s offset crash safety.This thesis takes one kind of MPV vehicle’s C-NCAP offset crash test as a research object. Establish the whole car crash finite element model and make the simulation of crash. Compared with the acceleration of B pillar and the deformation of vehicle body between test and simulation, the finite element model is proved to be valid. Combine with the result of test and simulation, the thesis analyzes the limitation of vehicle body structure design. That is the stiffness of front cabin not well matched. And two of most important crash force transfer ways are also not form stiffness degrees increase, which cause the cab deformed seriously during the offset impact test. The surrogate models optimization technique is used to optimize the structural thickness and improve a very important component’s configurable character. It matches the car’s front parts’stiffness and makes them deform reasonably. The result shows that the optimize design and modification effectively improve this kind of car’s 40% offset impact safety with considering the safety of full front impact and lightweight.