• 한국자동차공학회논문집
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• 제22권2호
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• pp.52-59
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• 2014

Front impacted SUV vehicle shows that the front parts of side members are collapsed by the bending due to the transverse load exerted at the end of side members. Side member models were impacted with various angles in order to study the crash performance according to the impact angle. Even for the small impact angle of $10^{\circ}$, crash performance seriously deteriorated and the deformations for impact angle $15^{\circ}$ were similar to those from the front body impact analysis. In addition, the angled front impact analysis for the straight member with hat section was carried out and the effects of inner reinforcement shape on crash performance was investigated.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.97-103
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• 2013

Crash performance of the straight member was studied by FE analysis. One end of model was fixed and the other end was impacted by 1,000kg rigid mass with velocity of 16.0m/sec. The maximum and mean load were discussed to compare crash performance. The members with various section shapes were analyzed and the flange location was changed. Also, spot weld points were added in the initial buckling region to investigate its effect. Final rectangular section model which has flanges at the center and reinforcement in initial buckling region showed high enhancement in crash performance.

• 대한기계학회논문집A
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• 제36권10호
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• pp.1155-1162
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• 2012

알루미늄 크래쉬 박스는 저속충돌조건에서 프론트 사이드 멤버를 변형을 방지하기 위한 부품이다. 본 연구에서는 저속충돌조건에서 비드형상이 알루미늄 크래쉬 박스의 충돌성능에 미치는 영향을 분석하였다. Edge concave, surface convex 와 surface concave 타입의 비드형상들에 대한 충돌해석 및 실험을 수행하여 비드가 없는 normal 타입의 알루미늄 크래쉬 박스의 충돌성능과 비교분석하였다. 충돌성능은 저속충돌조건에서 크래쉬 박스의 초기 최대하중 및 충돌에너지 흡수능으로 평가하였다. 이를 검증하기 위해 알루미늄 크래쉬 박스와 결합된 프론트 사이드 멤버에 대해 저속충돌실험 수행하고, 이를 분석하였다. Surface concave 타입의 비드가 삽입된 알루미늄 크래쉬 박스 경우, 프론트 사이드 멤버의 변형을 방지할 수 있음을 확인하였다.

• 한국정밀공학회지
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• 제30권11호
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• pp.1179-1185
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• 2013

In this study, the design optimization of the automotive side member is performed to maximize the crash energy absorption efficiency per unit weight. Design parameters which seriously influence on the frontal crash performance are selected through the sensitivity analysis using the Plackett-Burman design method. And also the design variables, which are determined from the sensitivity analysis, are optimized by two methods. One is conventional approximate optimization method which uses the statistical design of experiments (DOE) and response surface method (RSM). The other is a methodology derived from previous work by the authors, which is called sequential design of experiments (SDOE), to reduce a trial and error procedure and to find an appropriate condition for using micro-genetic algorithm. The proposed optimization technique shows that the automotive side member structure can be designed considering the frontal crash performance.

• 한국정밀공학회지
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• 제23권9호
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• pp.149-155
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• 2006

This paper is concerned with the weight reduction of front side member of a vehicle considering the application of high strength steel sheet. The influence of steel sheet grade and thickness on the energy absorption, impact load and deformed shape of front side member is investigated by using reverse engineering and FE-analysis. The reverse engineering is applied to obtain 3D model of front side member from B.I.W for the FE simulation. FE analysis is carried out with commercial crash analysis SW PAM-CRASH. The crashworthiness of front side member is considerably improved with steel sheet strength and thickness increase. From the result of this study the weight reduction in automotive parts for the improvement of the fuel efficiency can be easily achieved with replacing high strength steel without deterioration of crashworthiness.

• International Journal of Automotive Technology
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• 제8권1호
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• pp.93-102
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• 2007

The frontal crash optimization of an engine room member using the response surface method was studied. The engine room member is composed of the front side member and the sub-frame. The thicknesses of the panels on the front side member and the sub-frame were selected as the design variables. The purpose of the optimization was to reduce the weight of the structure, under the constraint that the objective quantity of crash energy is absorbed. The response surface method was used to approximate the crash behavior in mathematical form for optimization procedure. To research the effect of the regression method, two different methodologies were used in constructing the response surface model, the least square method and the moving least square method. The optimum with the two methods was verified by the simulation result. The precision of the surrogate model affected the optimal design. The moving least square method showed better approximation than the least square method. In addition to the deterministic optimization, the reliability-based design optimization using the response surface method was executed to examine the effect of uncertainties in design variables. The requirement for reliability made the optimal structure be heavier than the result of the deterministic optimization. Compared with the deterministic optimum, the optimal design using the reliability-based design optimization showed higher crash energy absorption and little probability of failure in achieving the objective.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.266-269
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• 2003

This paper is concerned with a forming analysis of front side members and the application of the forming effect in crash analysis of auto-body. Drawbead restraining forces are calculated with ABAQUS/Strandard in order to identify the boundary condition in forming process. Forming analysis with equivalent drawbead is carried out with LS-DYNA3D. In order to demonstrate the validity of the forming analysis, quantitative comparison of the thickness variation between the real product and the numerical simulation result is carried out. Forming histories obtained from the forming analysis are utilized as the initial condition of the crash analysis for accurate assessment of the crashworthiness.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1487-1490
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• 2004

In this study, the crash analysis was carried out to evaluate the influence of steel sheet grade and thickness on weight reduction and crash characteristics for front side member which had an important role of absorbing the impact energy during front and side impact. In order to achieve the aim of this study the reverse engineering was applied to obtain 3D model of front side member from BIW for the FE simulation. In the result, the crashworthiness of front side member is considerably improved with steel sheet strength and thickness increase. Also, the weight reduction in automotive parts for the improvement of the fuel efficiency can be easily achieved with applying high strength steel without deterioration of crashworthiness.

• 소성∙가공
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• 제20권8호
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• pp.555-561
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• 2011

The energy absorbing characteristics of crash members in a car collision play an important role in controlling the amount of damage to the passenger compartment. Crash members filled with aluminum foam are expected to have reduced mass while maintaining or even improving the crashworthiness compared to the conventional hollow-beam types. Finite element simulations are carried out in the present work to assess the improvement of crashworthiness by the use of aluminum foam fillers. The numerical results agreed well with experimental measurements. Parametric studies are conducted to analyze the effect of impact velocity, weld strength, and initiator on the crash response.

• 한국생산제조학회지
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• 제19권2호
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• pp.235-240
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• 2010

The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, energy absorbing members should be absorbed with collision energy sufficiently. But vehicle structure must be light weight for the environmentally-friendly aspect, in order to improve fuel efficiency and to reduce tail gas emission. Therefore, the light weight of vehicle must be achieved in a status of securing safety of crash. An aluminum or CFRP (Carbon Fiber Reinforced Plastics) is representative one among the light-weight materials. In this study, impact collapse behavior of circular hybrid thin-walled member is evaluated. The hybrid members are manufactured by wrapping CFRP prepreg sheets outside the aluminum circular members in the autoclave. Because the CFRP is an anisotropic material whose mechanical properties change with its stacking condition, special attention is given to the effects of the stacking condition on the collapse behavior evaluation of the hybrid thin-walled member. Collapse mode and energy absorption capability of the hybrid thin-walled member are analyzed with change of the fiber orientation angle and interface number.