Pretensioned Occupant Restraint System Simulation

Since accident rate is on the rise, people are more and more concerned with safety ofvehicle driving. They hope manufacture continuously improve safety technologies to protectpassages and passers. Safety belt was born with this idea. However, people have highdemands on vehicle safety, we hope to improve efficiency of seat belt protection system.Safety belt is combined with many systems and components, Continuous improve design andoptimize parameter is one way to increase safety of seat belt system.Main Purpose of this study is to increase passage protection level by improving seat belt.Safety belt have a lot of parameters, Among these parameters, First of all, select theparameters which have a greater impact on passages and these parameters are easily changed.When selected parameters are determined, optimized these parameters, try to increase passageprotection level of traffic accident.Main methods: by utilizing SOLIDWORKS software build three-dimensional models,then we can analyze structure of seat belt; Try to learn more about vehicle safety technicalregulations and passage injury assessment, to make our design comply with governmentregulations, as well as analyze report to increase optimization. By utilizing MADYMOsoftware establish Multi-body simulation model restraint system, which made up withrestraint system model and passage dummy model. Simulate force, acceleration andmovements by simulation belt, use sensitive analysis method select parameter which have agreater impact on passages, list parameter variation range of each parameters. Then makeindividual test refer orthogonal test tablet, by analysis of variance find out optimal parametercombination; using simulation software compare with injury index before and afterimprovements.Through above analyze and research, Belt tensioner lock-up time, preload of tensioner,webbing stiffness and force; these four parameters are the most sensitive to injury to passages,Moreover studies discovered lock-up time of0.2ms, preload of80mm, webbing stiffnesscharacteristics75%, force limiters3000N. Under this condition, belt system on the minimumlevel of injury, which means the seat belt system provide best protection of passages. This study is based on multi-body theory system, By MADYMO software successfullyestablish passage restraint system, combined with mathematical methods of sensitivityanalysis, orthogonal test and variance analysis to identify parameters which have a greaterimpact on the passages, and optimize these parameters. Combines and utilizes multi-bodytheory and knowledge of mathematical methods; to have a guideline of research belt systemwithin passage safety system.