• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.72-80
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• 2013

For the proper cooling of in-wheel motor, the cooling channel should have the characteristics which are low pressure drop and adequate cooling oil supply to motor part. In this study, the flow performance of cooling channel for in-wheel motor was evaluated and the shape of the channel was optimized. First, the pressure drop and flow distribution characteristics of the initial channel model were evaluated using numerical analysis. Also, by the result of analysis and design modification, 4 design parameters of the channel were selected. Second, using the Taguchi optimal method, the cooling channel was optimized. In the method, nine models with different levels of the design parameters were generated and the flow characteristics of each models was estimated. Base on the result, the main effect of the design parameters was founded and optimized model was obtained. For the optimized model, the pressure drop and oil flow rate were about 0.196 bar and 0.207 L/min, respectively. The pressure drop decreased by about 0.3 bar and the oil flow rate to the motor part increased by about 0.2 L/min compared to the initial model.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.3
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• pp.279-285
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• 2006

Recirculation for the unreacted fuel is necessary to improve the overall efficiency of the fuel cell system and to prevent fuel starvation since the fuel cell for a vehicle application is a closed system. In case of the automotive fuel cell, the ejector which does not require any parasitic power is good for the performance improvement and easy operation. It is essential to design the customized ejector due to the lack of the commercial ejector corresponding to the operating conditions of the fuel cell systems. In this study, the design methodology for the ejector customized to an automotive fuel cell is proposed. The model based sensitivity analysis prevents the time-consuming redesign and reduces the cost of developing ejector. As a result, the customized ejector to meet the desired performance within overall operating range has developed for the PEMFC automotive system.

• IEMEK Journal of Embedded Systems and Applications
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• v.9 no.2
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• pp.87-99
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• 2014

An AUTomotive Open System ARchitecture (AUTOSAR) is a de-facto standardized software platform, which developed for an automotive Electronic Control Unit (ECU) in global automotive industry. AUTOSAR improves the reusability and the scalability, thus the software development can be easier, faster and more reliable. However, it requires a lot of time and efforts to develop an AUTOSAR software due to the difficulties of understanding of massive AUTOSAR documentations and complicated usage of AUTOSAR design tools. AUTOSAR training is offered by AUTOSAR design tool venders but it is limited to introduction of their simplified concept and usages based on PC. Therefore the training is not enough for industrial developers or graduate students. In this paper we present an AUTOSAR starter kit which allows industrial engineers and graduate students to practice the detailed process of AUTOSAR software development easily and more conveniently. The kit is composed of a practical environment similar to actual automotive system and a textbook that explains how to design AUTOSAR software. And we demonstrated the validity of our methodology based on a case study.

• Korean Journal of Computational Design and Engineering
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• v.19 no.4
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• pp.316-323
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• 2014

This paper proposes the 3D modeling and simulation technique for predicting the integrated performance of combat vehicle. To consider the practical driving and firing condition of a combat vehicle, the full vehicle model, which can define the six degrees-of-freedom of vehicle motion and various firing angles, is developed. The critical design parameters such as the stiffness and damping coefficient of suspension system are applied to construct the analysis model of vehicle. A simple ballistic model, which incorporates the empirical interior ballistic model and the point mass trajectory model, is built to estimate the firing range and the firing recoil force. To predict the integrated performance and analyze the effect of system parameters, MATLAB/SIM-ULINK model of a combat vehicle for performing the real time simulation is also developed. Several simulation tests incorporating the road bump and the firing recoil force are presented to confirm the effectiveness of the proposed vehicle model.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.325-333
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• 2004

To ensure competitiveness in the modern automotive market, material arrangements and information managements should be performed concurrently with new car developments. In automotive general assembly shops, thus, new business workflow and supporting environments are inevitable to reduce the manufacturing preparation time in developing a new car in the manner of concurrent and collaborative engineering. Since complete material arrangements for a whole general assembly system is a huge and complex job, several planners should execute their planning jobs and share information. Therefore, each planner should provide others with his/her results with continuous on-line communication and cooperation. Digital automotive general assembly factory is useful the performing concurrent and collaborative engineering and is essential for material arrangements and information managements systems. In this research, we constructed a sophisticated digital factory of an automotive general assembly shop by measuring and modeling through the parametric 3-D CAD, and a web-based system for concurrent and collaborative material arrangements for automotive general assembly via 3D mock-up is developed. By the digital general assembly shop and developed web-based system, savings in time and colt of manufacturing preparation activities are possible, and the reliability of the planning result Is greatly improved.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.87-94
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• 2007

It has been argued that the use of plastics can cause problems during design and manufacture owing to their low strength, relatively poor thermal conductivity and large thermal expansion. However, the advantages of plastics e.g., corrosion resistance, low cost, curtailment of weight, design flexibility etc., can compensate abundantly for the disadvantages. This study analyzes and compares the heat transfer performance characteristics of automotive compact oil cooler composed of plastic tube bundle with conventional metal oil cooler on the same core area basis as diameter, tube thickness, number of tube or tube arrangement varies. The performance analyses are accomplished by use of computational fluid dynamics program Fluent 6.2, which is verified and compared with the results of performance tests. The result of analyses is coincided with that of experiments. Flow pattern at air side according to tube arrangement is dominant factor which affects heat dissipation in case of similar total heat transfer surface area.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.3
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• pp.50-57
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• 2013

The high temperature thermal attacks in welding can affect the residual stress of a frame for automotive assembly accompanying frame deformation. Also the residual stress can induce the negative effect on durability performance of the automobile. In order to analyze the frame deformation, the simplified test frame which had the similar shape (form) of the real automotive frame was fabricated. The contactless optical 3D scanner was used for the shape difference measurement of the frame between before and after the welding. The FE-model of the test frame was composed and the deformation and residual stress simulation were performed. The simulated results were compared with the measured results for the reference of the frame design following as the variation of welding sequency. The deformation shape of the frame by simulation was in good agreement with that by the experimental measurement. In addition, the optimized welding sequency with reduced deformation after welding could be achieved through these analyses.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.1
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• pp.153-158
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• 2005

Titanium alloy has widely been used as material for automotive parts because it has high specific strength. It is also light and harmless to human body. But, we have little design data about the creep behaviors of the alloy. Therefore, in this study, creep tests under four constant stress conditions have been conducted with low different temperature conditions. A series of creep tests had been performed to get the basic design data and life prediction of titanium products and we have gotten the fallowing results. First, the stress exponents decrease as the test temperatures increased. Secondly, the creep activation energy gradually decrease as the stresses became bigger. Thirdly, the constant of Larson-Miller parameter on this alloy was estimated as about 7.5. And for the last, the fractographs at the creep rupture showed the ductile fracture due to the intergranullar rupture.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.9
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• pp.817-823
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• 2017

In the past, research has been conducted on the development of an adaptive cruise control algorithm considering fuel efficiency, and an adaptive cruise control system considering fuel efficiency have been developed. However, research on optimizing vehicle and adaptive cruise control parameters in order to maximize performances is insufficient. In this study, the design optimization of vehicle and control parameters considering fuel efficiency, trackability, ride comfort and safe distance is performed. This paper proposes performance measures of vehicle behavior and develops an adaptive cruise control system. In addition, based on the screening of vehicle parameters that significantly influence performances, kriging surrogate models are constructed through a sequential design of experiment, and kriging surrogate model-based design optimization is performed to maximize fuel efficiency and satisfy target performances.

• Journal of Sensor Science and Technology
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• v.27 no.6
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• pp.397-402
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• 2018

Proper seat design is critical to the safety, comfort, and ergonomics of automotive driver's seats. To ensure effective seat design, quantitative methods should be used to evaluate the characteristics of automotive seats. This paper presents a system that is capable of simultaneously monitoring body pressure distribution and surface deformation in a textile material. In this study, a textile-based capacitive sensor was used to detect the body pressure distribution in an automotive seat. In addition, a strain gauge sensor was used to detect the degree of curvature deformation due to high-pressure points. The textile-based capacitive sensor was fabricated from the conductive fabric and a polyurethane insulator with a high signal-to-noise ratio. The strain gauge sensor was attached on the guiding film to maximize the effect of its deformation due to bending. Ten pressure sensors were placed symmetrically in the hip area and six strain gauge sensors were distributed on both sides of the seat cushion. A readout circuit monitored the absolute and relative values from the sensors in realtime, and the results were displayed as a color map. Moreover, we verified the proposed system for quantifying the body pressure and fabric deformation by studying 18 participants who performed three predefined postures. The proposed system showed desirable results and is expected to improve seat safety and comfort when applied to the design of various seat types. Moreover, the proposed system will provide analytical criteria in the design and durability testing of automotive seats.