简介:Thoughthebumperofavehicleplaysamajorroleinprotectingthevehiclebodyagainstdamageinlowspeedimpacts,manybumpers,particularlyinlargevehicles,aretoostiffforpedestrianprotection.Indesigningabumperforanautomobile,pedestrianprotectionisasimportantasbumperenergyabsorptioninlowspeedcollisions.Topreventlowerextremityinjuriesincar-pedestriancollisions,itisimportanttodeterminetheloadingsthatcarfrontstructuresimpartonthelowerextremitiesandthemechanismsbywhichinjuryiscausedbytheseloadings.Thepresentworkwasfocusedongainingmoreinsightintotheinjurymechanismsleadingtobothligamentdamageandbonefractureduringbumper-pedestriancollisions.TheEuropeanEnhancedVehicle-safetyCommittee(EEVC)legformimpactormodelwasintroducedandvalidatedagainstEEVC/WG17criteria.ThecollisionmechanismbetweenabumperandthislegformimpactorwasinvestigatednumericallyusingLS-DYNAsoftware.Toidentifytheeffectofthebumperbeammaterialonleginjuries,fouranalyseswereperformedonbumpersthathadthesameassemblybutweremadefromdifferentmaterials.