Development Of Subject-specific Occupant Finite Element Model And Its Application In Collision Safety Design

With the rapid development of the automobile industry,road traffic accidents have become one of the most important causes of human casualties.A large number of accident statistics have shown that older and obese occupants tend to have a higher risk of injury in vehicle crashes than a normal mid-aged male occupant.As the population ages and the rate of obesity increases,the number of casualties among such vulnerable people will increase further in traffic accidents.At present,many advanced safety technologies are continuously applied to vehicle occupant restraint systems to improve the collision safety of occupants.However,most of these restraint systems are developed for middle-aged male occupants of normal body type,and cannot provide effective protection for diverse body types occupants.At present,there is a lack of human injury assessment tools to study the collision damage of aging and obese occupants.To address the above problems,this paper focuses on the development of subject-specific occupant finite element model and its application in collision safety design.By studying the radial basis interpolation function and the marker point selection method,an efficient mesh deformation technique for human body finite element modeling is proposed.Taking the normal female elderly human body finite element model CHARM-70 F as the baseline model,the elderly female body finite element models with different obesity characteristics were quickly obtained by the efficient mesh deformation technique.These built elderly female body finite element models can be validated with cadaveric test data.The frontal collision models of elderly women with different obesity characteristics were established.The impact injury of occupants with different body types was compared and analyzed.The influence of obesity on the collision damage of elderly female occupants was discussed.Based on the optimized design method,an occupant restraint system corresponding to the design parameters was developed for the subject-specific occupant.Finally,a set of research methods,including occupant finite element model development technology,human body model verification method,human injury analysis method and occupant restraint system optimization design method was developed to form a subject-specific occupant collision safety system,which provides a basis for occupant protection of diverse human body features.The research results show that the mesh deformation technology proposed in this paper can quickly develop a subject-specific occupant human body finite element model.The subject-specific occupant finite element model was verified by performing local experiment simulations such as chest impact,abdominal impact,shoulder impact and pelvic impact.By analyzing the head injury risk,neck injury risk,chest injury risk,lower limbs injury risk and comprehensive injury of the subject-specific occupant finite element model,it can be concluded that compared with the normal body type,the elderly women with lean body shape,overweight body type and obese body type are in the collision process had a higher risk of comprehensive injury.By optimizing the design parameters of the occupant restraint system,the risk of comprehensive injury in elderly women with lean body size was reduced by 6.08%,the risk of comprehensive injury in elderly women with overweight body size was reduced by 7.77%,and the risk of comprehensive injury in elderly women with obese body size was reduced by 10.17%.