Instrument panel assembly is a key component in automotive interiors and also inside the car the most compelling parts. Instrument panel assembly in addition to meet the functional requirements, but also to meet the requirements of many safety regulations, including the occupant crash protection requirements (head-on collision, knee collision), human engineering requirements, appearance requirements. Computer-aided design technology to quickly on the instrument panel assembly of the modal properties, stiffness, head-on collision performance indicators to evaluate the structural design guidance to reduce development costs. Firstly, based on the basic structure of the dashboard assembly, the establishment of the instrument panel assembly of the static analysis model. In order to test the vibration characteristics of the dashboard assembly, instrument panel assembly reference modal testing requirements, calculated binding instrument panel assembly - free mode; to verify the instrument panel assembly of the stiffness, the analysis of the vertical acceleration of gravity 2g ; according to the results of sensitivity analysis, select one of 21 components as the design variables to the total mass of the dashboard assembly the minimum as the optimization goal, instrument panel assembly and the modal properties of stiffness as a constraint function, the size optimization; in the reference European regulations ECE 21 are the effective head-on collision in the region of 10 selected points head-on collision simulation. The results showed that the overall instrument panel assembly of the first order natural frequency of 35.6Hz, above the standard requirements of 34Hz, the overall good performance mode; instrument panel assembly, the maximum displacement of 0.73mm, far less than 2mm of the request, the total dashboard into the stiffness of good; optimized, the quality of the instrument panel assembly before optimization 38.14Kg down to 35.86Kg, weight ratio of 5.98%; there are two locations does not meet the regulatory requirements, mainly just to spend a large part, the structure should be further changes. In addition this paper, the sensitivity is not better, should be conducive to the objective function and constraint functions to filter the angle variable, and that variable selection should be in accordance with the following steps: first select the most sensitive of the objective function variable; second selection is conducive to weight loss constraint function is also beneficial to the convergence of the variables; and then choose the constraint functions are not sensitive to the variable; and then select the constraint function is not conducive to the convergence of the variables and to exclude the selected variables; the last variable in the removal of parts can not be changed. In view of the domestic research on the dashboard less head-on collision case, this article on the instrument panel on domestic and international laws and regulations head-on collision head-on collision on a number of issues were discussed, including the determination of the head impact area, exemption region OK, the selection of head-on collision point, impact point and impact angle determination. And reached the European laws and regulations in the United States on the definition of head-on collision region is basically the same, but the point of impact in the exemption and impact areas and determining the angle is very different.This instrument panel assembly of modal analysis related to occupant comfort, head of the instrument panel assembly of collisions related to occupant safety, the improvement of vehicle technology has made great contribution.
Key words: instrument panel, mode, size optimization, head-on collision, the effective head-on collision region
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