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Recently, researches of pedestrian protection have been actively studied by automotive designers and engineers due to the enhanced pedestrian protecting regulations. It is required to design an energy absorbing structure, such as crumple zone that can sufficiently absorb the impact energy to reduce the leg injury when accident happens. The structure is designed by reducing the height of front end module, considering the mounting location, and impact characteristics. In this paper, the concept of the crumple zone was introduced and the role of the crumple zone was investigated by analyzing the performance of upper legform impact to a bonnet leading edge, and the design process was suggested.

This paper presents a study on prediction of ductile failure in metals using the combination of a void growth model and a constitutive law for the void containing solid. The void growth model is a modification of the well established McClintock criterion whereas the constitutive law is the modified Gurson's model. An advantage of the proposed criterion is the capability of predicting not only the onset failure but also the propagation direction by evaluating the rate of void growth in different principal stress directions. Moreover, by introducing a Lode angle dependent parameter to define the loading asymmetry condition, the shear effect is also taken into account. The proposed criterion was implemented using user-subroutines in ABAQUS. The model was calibrated and correlated by the uniaxial tension, shear and notched specimen tests. Numerical results were validated by comparing with the test data.

Wheel bearing seals are required to have strong sealing capabilities and low reaction forces because the bearing operates in extreme environments such as mud and water. And the design technology for wheel bearing seals is closely related to the efficiency and durability of the entire bearing. If the bearing seal performance can be estimated and used in the design procedure, more efficient and durable bearing seals can be produced. The bearing seal performance is strongly dependent on the shape of the bearing seal lip, so the optimization of the bearing seal design is more efficient if the design factors of the seal lip are known in advance. In this study, deformation patterns of seal lips are predicted by finite element analyses considering nonlinear characteristics of rubber material, and the shape is optimized using experimental design method applying parameters obtained from the analyses.

This study presents the development of a new aluminum seat frame for commercial bus which is lighter than steel seat frame about 40%. The seat components i.e. back frame, main cross pipe and side frame are designed to satisfy several FMVSS regulations through tests and numerical analyses. The analysis was done for seat belt anchorage test and back moment test. The final design was used to produce a sample seat. Substitution of the material resulted in a weight reduction effect with equivalent strength characteristics.

In this study we suggest simplified and design oriented hybrid modeling methodology to the development of crashworthy structure. This hybrid model consists of main structure, which are modeled by beam and springs and doors modeled by shells. The main structures such as B-pillar roof rail and side sill are represented by nonlinear springs which have the same section properties as shell model have. The localized collapse of main structures are represented by non-linear spring elements whose moment-rotation characteristic is calculated based on Wierzbicki’s equation. The joint parts are represented by non-linear springs, which have the same moment-rotation characteristics as those of real parts to hold actual collapse characteristics. To represent force transition between structure and door, anti-sliding shells are introduced in the area of side-sill and lower part of Bpillar.

In order to obtain an automatically designed shape of engine mount, an optimum shape design process of engine mounting rubber is introduced. After the primary stiffness values of an engine mount system are determined, the secondary stiffness values and the shapes are designed. By using nonlinear spring analysis, the design of the secondary stiffness and the gap size of engine mount can be carried out. In this work, the finite element program including the optimization code is developed and used. The optimum shape design process of engine mounting rubber using a parametric approach is suggested. The optimization code is used with the commercial nonlinear finite element program to determine the shape to satisfy the stiffness requirements of engine mounts. An engine mount system used in a passenger car is chosen for an application model. Three engine mounts are designed by the procedure mentioned above.