With the introduction of the lower leg injury criteria in the new European Frontal Impact Legislation, the leg kinematics and loading mechanisms must be considered at an early stage in vehicle development programmes. Finite Element codes such as LS-DYNA3D are used increasingly to model occupant.structure interactions for vehicle design, from concept to the final restraint system optimisation. A fully validated Hybrid III lower leg model is consequently an essential tool in the vehicle design process. However, due to the complex nature of the materials and geometry of the lower leg and footwell, development of such a model presents a number of problems. In the collaborative LLIMP project (Lower Leg Injuries and Methods of Prevention vehicle design project), MIRA, with the project sponsors, Jaguar, Ford and Rover, has developed a Finite Element computer model of the Hybrid III lower leg which can be attached to a full Hybrid III Finite Element dummy model. The model has been used to support vehicle design as well as evaluating the effects of footwell intrusion and occupant position on lower leg injury criteria. The paper presents the development of the lower leg model, which includes the use of lower leg component tests and HyGe sled tests to validate the material models, contact characteristics and load levels. HyGe sled tests have been simulated to which lower leg kinematics, loading mechanisms and injury criteria have been correlated. (A)
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