Study On The Parametric Division Method Of Engine Hood Impact Area Based On Siemens NX

The headform crash of pedestrian is the fatal factor without in pedestrian death in traffic accidents. Additionally, engine hood is the main region which directly leads to serious head injury or even death of pedestrian. Therefore, the key point to prevent pedestrian injury is the protection performance of engine hood. Furthermore, the location and affect region of head impact during engine hood crash test is especially important. The efficiency and veracity of division of the engine hood impact area played an important role in the efficiency and determination accuracy of whole simulation process.It is more complicated to determine the location of headform impact with tradition manual method during pre-processing in simulation of engine hood-pedestrian collision. The division process based on computer models has the same problems about efficiency and accuracy. Moreover, once the model of car body changed, it is necessary to repeat the routine. The testing personnel consume his time and energy to divide the impact area and iterative because of scheme changing. Meanwhile, it will have an adverse effect. In this paper, UG/NX software combines knowledge engineering with further development. According to the deficiency in the simulation of pedestrian collision engine hood, the parameterized system of fast division of headform impact area is developed. In this paper, the impact area of engine hood is divided and the parameters are extracted. The key algorithms of the determination of side reference line and wrap around distance are researched. And then, the impact area is divided automatically combined with a variety of development tools based on UG/NX platform. Then the function of intelligentization, parameterization and automatic update about the design of area division is achieved. The system can automatically recognize the new input model and update the impact area if the input model is edit or modified in the design process.In this paper, taking a car model for examples, the operation process of automatic partitioning system is described in detail. This process showed the system can divide the headform impact area quickly. And the fast division method is more efficiency than tradition manual method. In order to validate the useful efficiency of the system and test the accuracy of the division result, the impact area is divided by manual method. Comparing the efficiency of the two method shows that the system can simplify complicated work in preprocessing of the simulation analysis, thereby the simulation period is cut down greatly.