• 한국자동차공학회논문집
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• 제18권5호
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• pp.50-55
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• 2010

In recent years, the development of fuel cell vehicles has further accelerated because of environmental problem and petroleum resources shortage. The fuel cell vehicles have the stack which converts fuel to electricity. The stack is usually mounted by bush to isolate the vibration of chassis and body. This paper analyzed the vibratory characteristics of stack and chassis, body system. The wheel forces of fuel cell vehicle are measured to estimate the road load data. And the paths of vibration from wheel to stack are analyzed by CAE. According to the test and CAE results, the improvement of stack vibration are evaluated.

• 열처리공학회지
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• 제35권2호
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• pp.66-73
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• 2022

Partial-hardened hot stamping has been well known to be very effective to absorb more energy in automotive lateral crash. Hardness distribution and dimensional change after partial-hardened hot stamping have been studied to find out effect of thermal deformation of the heated hot stamping die on dimensional accuracy of automotive center pillar. Soft zone of commercial center pillar showed 275~345 in Vickers hardness, indicating bigger non-uniformity which resulted from thermal deformation of heated die. Dimensional changes in soft zone of the commercial center pillar measured by three dimensional scanner were much bigger than that in hard zone. It has been found that hot stamping die compensation considering thermal deformation in soft zone causes a significant decrease in hardness deviation in the soft zone, corresponding to 20 percent of commercial center pillar and subsequently leads to much higher dimensional accuracy.

• 한국자동차공학회논문집
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• 제19권6호
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• pp.30-36
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• 2011

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA Sine with dwell steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes useful worst case based upon the existing worst case scenarios mentioned above and worst case evaluation for vehicle dynamic controller in simulation basis and UCC HILS. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of both yaw rate and side slip angle. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle dynamic control system.

• 한국산학기술학회논문지
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• 제12권11호
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• pp.4751-4755
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• 2011

본 연구는 자동차용 시트 Back frame 내부에 설치하여 탑승자의 등부분을 지지하며 편안한 승차감을 제공하는 시트용 서스펜션 시스템에 대한 연구이다. 운전자의 등 전체를 고르게 지지하는 구조로 설계하고 시트 백 프레임과 플라스틱 서스펜션의 조립을 효과적으로 할 수 있는 구조로 개발 하고자 한다. 서스펜션 단품은 운전자의 체압 분포를 고려하여 설계하고 시뮬레이션 해석에 있어서는 실제 모델과 같은 크기를 가지고 하였다. 플라스틱 서스펜션의 해석결과가 실제 측정값에 근접함을 확인하였으며 기존 Wire Type에 비해 양호한 체압분포를 얻을 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.363-369
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• 2000

Due to environmental problem for reduction in fuel consumption, vehicle emission and etc., many automotive makers are trying to reduce the weight of the vehicle. The most effective way to reduce the weight of vehicle is to use lighter materials, aluminum, plastics. Aluminum Space Frame has many advantages in weight reduction, body stiffness, ease of model change and so on. So, most of automotive manufacturers are attempting to develope Aluminum Space Frame body. For these reasons, we have developed Aluminum Intensive Vehicle based on steel monocoque body with Hyundai Motor Company. We achieved about 30% weight reduction, the stiffness of our model was higher than that of conventional steel monocoque body. In this paper, with optimization using FEM analysis, we could get more weight reduction and body stiffness increase. In the long run, we analyzed by means of simulation using PAM-CRASH to evaluate crush and crash characteristic of Aluminum Intensive Vehicle in comparison to steel monocoque automotive.

• 오토저널
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• 제23권4호
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• pp.15-22
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• 2001

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.241-244
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• 2008

Automotive companies have conducted a study for light weigh body and crash safety. But It is difficult to adapt a mass production because of formability with high strength steel in the conventional stamping process. Recently, Automotive maker in the Europe, USA, Japan has applied a hot stamping with boron steel in the body structure. Hot stamping technology spread fast in various body parts of automobile. Bumper beam has been applied in the foreign automotive company so much nowadays. In this study, We will optimize crash performance of bumper beam using hot stamping through comparison with conventional bumper beam.

• 한국자동차공학회논문집
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• 제22권5호
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• pp.1-4
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• 2014

In recent years, requests for automotive seat comfort are increasing. An important issue of them is long-term seat comfort. Until now, the study for long-term seat comfort has been studied mainly using driver's questionnaire, changing adrenalin and electromyography. Actually the results and methodologies of them are difficult to apply to seat development and design because of money and time required. In this study, we developed Seating Feel Curve for seat comfort evaluation and a long-term seat comfort evaluation which can be applied to the development of seat comfort using seat support.

• 소성∙가공
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• 제7권4호
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• pp.382-392
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• 1998

Computer simulations and test trials were carried out to obtain the optimal stamping conditions of the die design of the laser welded automotive body. The stamping process including gravity deflection bead calibration binder wrap, forming and spring back was simulated and compared with the results obtained from test trials. The production variables were determined from a preliminary operation and they were investigated in the simulation and the test trials. The formability was tested under the various conditions, such as the initial position of blank, blank holding force, corner radius and the shape of drawbead. Sound products without fracture, wrinkling and excessive weldline movement were produced by applying results obtained this investigation.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.178.2-178
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• 2001

Today, many electronic devices and ECUs (Electronic Control Units) are used in the automotive body control systems. It becomes more common that these devices exchange data with others through an in-vehicle network. Automobile manufacturers concentrate their efforts on development of body control systems based on networks in order to save cost and to increase flexibility and safety. OSEK/VDX has been founded as a joint project in German and French automotive industry aiming at an industry standard for an open-ended architecture for distributed control units in vehicles OSEK/VDX consists of Communication (specification of data exchange within and between control units), Network Management specification of Configuration determination and monitoring and Operating System (specification of realtime executive for ECU software ...