Establishment Of Finite Element Model Of The Elderly And Its Application In Automobile Collision

As the world’s population ages,the proportion of drivers in the elderly is rising.However,due to the decline in physical function and the tolerance of injuries,the elderly have a high rate of mortality and injury in car accidents,becoming a "vulnerable group".It is also an important issue in the field of occupant collision safety.Literature study found that previous research on occupant safety mainly focused on the adult and child.Although scholars have paid more and more attention to the injury of the elderly in a car collision in recent years,there are few tools available for the evaluation of the body injury in the elderly.Therefore,in order to study the kinematic response and injury mechanism of the elderly in a car collision,an elderly female occupant FEM is developed and validated in this paper.Then it is applied to the car crash simulation research.The specific research work is as follows:1.Participated in the model development process of the finite element model of the elderly in the Center for Biological Engineering of Wayne State University(WSU),and carry out the assembly work of the finite element model of the ligament,the joint hinge and the neck muscle reconstruction of the elderly driver.Debug the final model to meet the basic requirements of the calculation.2.Based on the PMHS data of isolated organs experiment in the literature,the component-level validation work of the vital organs and tissues(including the head,neck,chest,lumbar vertebrae,pelvis,and femur)of the elderly driver model is performed.The geometry,mesh and material model of the finite element model are carefully modified and optimized according to the model verification results.3.The whole finite element model of the elderly is validated against the PMHS data in the literature,including the whole model frontal collision test and the whole model side sled test.4.The validated FEM of the elderly is applied to the human collision safety study.The simulations are performed to identify the biomechanical response and injury of the elderly occupant model when impacted by a steering wheel under the condition of no seat belt restraint in a low-speed collision.Protection advice provided for the protection of the elderly.The results show that the developed finite element model of the elderly driver has high bio-fidelity.The model is validated against the PMHS data both in component level and whole-body level.This elderly model can accurately simulate the collision response of the elderly female driver under the conditions in validation simulations.The injuries of the elderly occupant when they at low speed by the steering wheel without seat belt restraint are:neck interspinous ligament(ISL)strain,and left and right side 4-6 rib fractures.There may be chest internal organs and soft tissue contusions.The elderly model needs to be more fully verified and supplemented in the prediction of injury forms to show the injury phenomenon more comprehensively and intuitively.The results of this paper provide an important evaluation tool for the biomechanics and injury prediction of elderly female occupants in vehicle collisions,and have certain guiding significance for the occupant protection of the elderly population.