Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinem...Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinematics,which lack in-depth study on the fractures in stress analysis.This paper aims to investigate lower limb impact biomechanics in real-world car to pedestrian accidents and to predict fractures of long bones in term of stress parameter for femur,tibia,and fibula.For the above purposes,a 3D finite element(FE) model of human body lower limb(HBM-LL) is developed based on human anatomy.The model consists of the pelvis,femur,tibia,fibula,patella,foot bones,primary tendons,knee joint capsule,meniscus,and ligaments.The FE model is validated by comparing the results from a lateral impact between simulations and tests with cadaver lower limb specimens.Two real-world accidents are selected from an in-depth accident database with detailed information about the accident scene,car impact speed,damage to the car,and pedestrian injuries.Multi-body system(MBS) models are used to reconstruct the kinematics of the pedestrians in the two accidents and the impact conditions are calculated for initial impact velocity and orientations of the car and pedestrian during the collision.The FE model is used to perform injury reconstructions and predict the fractures by using physical parameters,such as von Mises stress of long bones.The calculated failure level of the long bones is correlated with the injury outcomes observed from the two accident cases.The reconstruction result shows that the HBM-LL FE model has acceptable biofidelity and can be applied to predict the risk of long bone fractures.This study provides an efficient methodology to investigate the long bone fracture suffered from vehicle traffic collisions.展开更多
基于THUMS(total human model for safety)下肢长骨有限元模型,在材料和单元属性等方面进行了改进.在详细分析行人下肢长骨载荷特点的基础上,采用多种不同载荷工况下较新的生物力学实验数据,对长骨模型进行了前-后和外-内加载方向的准...基于THUMS(total human model for safety)下肢长骨有限元模型,在材料和单元属性等方面进行了改进.在详细分析行人下肢长骨载荷特点的基础上,采用多种不同载荷工况下较新的生物力学实验数据,对长骨模型进行了前-后和外-内加载方向的准静态三点弯曲验证,同时对近心端1/3处、中部和远心端1/3处加载的动态三点弯曲验证.验证结果表明,该模型具有较好的生物逼真度,能够准确地模拟行人下肢长骨的骨折及碰撞响应,可用于后续行人下肢模型的开发,并为行人下肢损伤机理和安全防护研究提供准确高效的研究手段.展开更多
基金supported by National Hi-tech Research and Development Program of China (863 Program,Grant No. 2006AA110101)"111 Program" of Ministry of Education and State Administration of Foreign Experts Affairs of China (Grant No. 111-2-11)+1 种基金General Motors Research and Development Center (Grant No. RD-209)Project of State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,China (Grant No. 60870004)
文摘Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinematics,which lack in-depth study on the fractures in stress analysis.This paper aims to investigate lower limb impact biomechanics in real-world car to pedestrian accidents and to predict fractures of long bones in term of stress parameter for femur,tibia,and fibula.For the above purposes,a 3D finite element(FE) model of human body lower limb(HBM-LL) is developed based on human anatomy.The model consists of the pelvis,femur,tibia,fibula,patella,foot bones,primary tendons,knee joint capsule,meniscus,and ligaments.The FE model is validated by comparing the results from a lateral impact between simulations and tests with cadaver lower limb specimens.Two real-world accidents are selected from an in-depth accident database with detailed information about the accident scene,car impact speed,damage to the car,and pedestrian injuries.Multi-body system(MBS) models are used to reconstruct the kinematics of the pedestrians in the two accidents and the impact conditions are calculated for initial impact velocity and orientations of the car and pedestrian during the collision.The FE model is used to perform injury reconstructions and predict the fractures by using physical parameters,such as von Mises stress of long bones.The calculated failure level of the long bones is correlated with the injury outcomes observed from the two accident cases.The reconstruction result shows that the HBM-LL FE model has acceptable biofidelity and can be applied to predict the risk of long bone fractures.This study provides an efficient methodology to investigate the long bone fracture suffered from vehicle traffic collisions.
文摘基于THUMS(total human model for safety)下肢长骨有限元模型,在材料和单元属性等方面进行了改进.在详细分析行人下肢长骨载荷特点的基础上,采用多种不同载荷工况下较新的生物力学实验数据,对长骨模型进行了前-后和外-内加载方向的准静态三点弯曲验证,同时对近心端1/3处、中部和远心端1/3处加载的动态三点弯曲验证.验证结果表明,该模型具有较好的生物逼真度,能够准确地模拟行人下肢长骨的骨折及碰撞响应,可用于后续行人下肢模型的开发,并为行人下肢损伤机理和安全防护研究提供准确高效的研究手段.