Many automotive components for power generation such as motors and alternators have been widely using ferrite magnets. To ensure a high level of efficiency could be achieved in an alternator, the assembled magnets must be in good enough durability. Recently, some hairline cracks have been found on the magnet produced by manufacturers in Korea. Thus, there is an increasing concern that some of the magnets produced could cause further problems after being assembled in the alternator. Based on the standard alternator test (RS0008 : 2006), this paper has developed an accelerated failure-free test for magnets in alternator to demonstrate that assembled magnets will meet durability objective specified by the manufacturer. This guarantees the target life of the magnet with 90 percent reliability and 90 percent confidence level (R90C90). Temperature and rotation speed were selected as accelerated stress factors.

For a die casting mold, generally, the casting layout design should be considered based on the relation among injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects was differentiated according to the various relations of the above conditions. In this research, in order to optimize the casting layout design of an automotive Oil Pan_DX2E, Computer Aided Engineering (CAE) simulation was performed with two layout designs by using the simulation software (AnyCasting). The simulation results were analyzed and compared carefully in order to apply them into the production die-casting mold. During the filling process with two models, internal porosities caused by air entrapments were predicted and also compared with the modification of the gate system and overflow. With the solidification analysis, internal porosities occurring during the solidification process were predicted and also compared with the modified gate system.

Among many potential problems associated with automobiles, the problem regarded as most sensitive and important to the customers is the automobile’s quietness. In particular, because the trend toward the high-performance automobiles is increasing, the quietness should be considered reflecting the increasing demand of the customers for the comfort of automobile ride. Road noise is the low-frequency range in the region of 20Hz to 350Hz, generated when the tires are making contacts with the rough road surface while the automobile is running, in which the noises are resonating within the passenger compartment or with the automobile suspension. In this research, among the factors related to the road noise, the influencing factors associated with the suspension and the tire design were investigated. In particular, among the tire design factors, the structure and the rubber material were investigated as the influencing factors, and for the investigative purpose, experimental tires were manufactured and road noise evaluations were conducted thorough actual feeling tests. Then the test results and correlations were analyzed using the 6-Sigma statistical method. Results from this study shows that, among the tire design factors, the apex is the most influencing factor, in which the height of the apex is the key. The influential factors were found out to be apex height, belt angle, and tread hardness, in that order, and when the suspension is of a same kind, the tendency of the road noise was found to be similar.

In this study, recliner is modelled and compared with 2 types of models as conventional recliner and round recliner by investigating stress and displacement through strength analysis. The maximum deformation of 0.018mm at round recliner is much smaller than that of 0.18mm at conventional recliner. It can be seen that the round recliner has more safety than conventional recliner. Round recliner model has more durability and safety than conventional model by the result of structural and vibration analysis. The model design of automotive recliner can be designed effectively at applying the safe driving of automobile practically by using the result of this study.

Numerical analysis of a Ni-PZT stacked piezoelectric micro actuator is investigated for the prediction of mechanical behavior as a preceding research for the manufacturing of three dimensional micro structures. Finite element method is adopted to examine the simulation of a piezoelectric actuator according to applied direction of voltage, by researching displacement characterization of piezoelectric material through piezoelectric theory. PZT-4 is selected as a piezoelectric material. And bimorph finite element modeling is employed to study the response of Ni-PZT bi-layered micro actuator under the various input voltages. The results are presented as maximum displacement values under each applied voltages. Maximum displacement of 0.71μm at 60V is obtained

This study aims to evaluate structural safety through FEM on the hollow shaft and the shaft filled with aluminum foam as the impact beam made of high tensile strength steel, Force reactions of impact beams are investigated when the forced displacement of 50mm is applied equally on two beams. When impact velocity of 80km/h is applied onto impact beams equally with the limit velocity of automobile on national road, how much impact energies can be absorbed by beams are also investigated. As study result, impact beams without aluminum foam and with aluminum foam show the maximum reaction forces of 15.53kN and 20.34kN respectively in case of the forced displacement of 50mm. As impact analysis result, impact beams without aluminum foam and with aluminum foam can absorb impact energies of 560J and 820J respectively. As impact beam with aluminum foam has reaction force and impact energy more than 23% and 30% than without aluminum foam, impact beam with aluminum foam has more safety than without aluminum foam.

차량용 시트는 쿠션부와 철제 구조물로 되어 있는데 철제 구조물은 프레임, 레일, 리클라이너로 구성된다. 특히 시트의 안정성과 직결된 리클라이너(Seat recliner)부품의 복합 성형제품은 파인블랭킹 제조기술을 활용하여 제작하는 연구가 진행되고 있다. 본 연구에서는 열처리 된 구조용강이 적용된 리클라이너를 CATIA 프로그램을 사용하여 3D 모델링하였으며, 이를 유한요소 해석 프로그램을 사용하여 라운드 리클라이너와 기준의 리클라이너의 강도 해석의 하중전달 경로, 응력 및 변형률을 연구하였다. 따라서 본 연구에서는 라운드 리클라이너와 기준의 리클라이너의 강도 해석의 응력 및 변형률을 비교/분석하였으며 기계적 특성을 파악했다.

본 논문에서는 와이어 하네스의 피로 내구 수명을 예측하기 위해 와이어, 번들, 실차단계의 유한요소 해석 방법론이 연구되었고 이를 위한 피로 내구 시험 기기가 개발되었다. 와이어 하네스 시스템을 구성하는 5가지 종류의 와이어에 대한 응력-수명 그래프를 얻기 위해 개발된 피로 시험기를 이용하여 반복 굽힘 움직임을 인가하였다. 와이어를 구성하는 도선과 피복의 재료 모델링을 위해 혼합의 법칙이 적용된 등가모델을 이용하였다. 번들 해석과 시험을 통하여 와이어 간의 접촉조건과 번들의 테이핑조건이 정립되었다. 와이어 및 번들 단계의 결과들은 실차 단계의 해석에 적용되었다. 실차단계의 해석을 위해 번들과 그로맷으로 구성된 와이어 하네스 시스템을 수치적으로 모델링 하였으며, 차량 문의 개폐조건이 와이어 간의 접촉조건과 함께 적용되었다. 유한요소 해석을 이용한 실차 모델의 피로 내구 해석을 통해 70만회 이상의 피로 수명이 도출 되었으며, 실차 조건의 시험 결과와비교하여 타당성을 검증하였다.

Magnetostrictive thin films can be applied in transmission system for the enhancement of energy efficiency. In this study, four kinds of substrates (Si, glass, Fe, polyimide) with the magnetostrictive thin film layers are prepared and investigated to characterize the magnetic and mechanical behaviors due to the substrates effects. The fabricated substrates have thicknesses of 50, 150 and 500um with cantilever shape. TbDyFe films are deposited by DC magnetron sputtering with 1～10m thick. The deposited film thicknesses are verified using X-ray diffraction. The magnetization of each sample is examined using VSM(Vibrating Sample Magnetometer) and magnetostriction is also measured using capacitance method to characterize magneto-mechanical behaviors. The magnetostriction results as deflections are compared and the results are discussed for micro actuator applications.

Silicon based magnetostrictive structures were fabricated for micro-wireless actuators, and finite element models were developed to predict mechanical characteristics of the actuated structures. These structures can be used to design wireless automotive parts and multi-function packaged micro automotive devices. In the fabrication process, amorphous magnetostrictive films of the optimized binary compound Tb0.4Fe0.6 and Sm0.47Fe0.53 were deposited with various thicknesses on the silicon membrane by DC magnetron sputtering using cast composite targets. Magnetic fields lower than 2KOe (0.2T) were applied for micro-system applications. These films have been tested in a simple cantilever arrangement and the predicted magnetostrictions of the actuated membranes through the developed FE models have been calculated.

In order to determine the wear properties of CVD ceramic coatings, wear process was evaluated using the coated pin of Falex Tribosystem. Also, in order to determine the effects of coating material on wear process, TiC,N of thickness 5m∼6m coated by Thermal CVD method were applied. The wear property of TiC,N film, the higher the deposition temperature was, the closer the lattice parameter was to the amount of the standard power, and the grain size increased. According to the wear formation, under the control that there is on specific wear rate wear parameter and coating delamination, decrease with increasing sliding friction and when the coating delamination happened.

Since the basic built-in-test, prognostic health management (PHM) has evolved into more sophisticated and complex systems with advanced warning and failure detection devices. Aerospace and military systems, manufacturing equipment, structural monitor- ing, automotive electronic systems and telecommunication systems are examples of fields in which PHM has been fully utilized. Nowadays, the automotive electronic system has become more sophisticated and increasingly dependent on accurate sensors and reliable microprocessors to perform vehicle control functions which help to detect faults and to predict the remaining useful life of automotive parts. As the complication of automotive system increases, the need for intelligent PHM becomes more significant. Given enormous potential to be developed lays ahead, this paper presents findings and discussions on the trends of automotive PHM research with the expectation to offer opportunity for further improving the current technologies and methods to be applied into more advanced applications.

In modern systems design and development, one of the key issues is considered to be related with how to reflect faithfully the stakeholder requirements including customer requirements therein, thereby successfully implementing the system functions derived from the requirements. On the other hand, the issue of safety management is also becoming greatly important these days, particularly in the operational phase of the systems under development. An approach to safety management can be based on the use of the failure mode effect and analysis (FMEA), which has been a core method adopted in automotive industry to reduce the potential failure. The fact that a successful development of cars needs to consider both the complexity and failure throughout the whole life cycle calls for the necessity of applying the systems engineering (SE) process. To meet such a need, in this paper a method of FMEA is developed based on the SE concept. To do so, a process model is derived first in order to identify the required activities that must be satisfied in automotive design while reducing the possibility of failure. Specifically, the stakeholder requirements were analyzed first to derive a set of functions, which subsequentially leads to the task of identifying necessary HW/SW components. Then the derived functions were allocated to appropriate HW/SW components. During this design process, the traceability between the functions and HW/SW components were generated. The traceability can play a key role when FMEA is performed to predict the potential failure that can be described with the routes from the components through the linked functions. As a case study, the developed process model has been applied in a project carried out in practice. The results turned out to demonstrate the usefulness of the approach.

This study analyzes lifes and damages at automotive tie rod through the structural analyses with fatigue. The structural result of this study can be effectively utilized with the design of automotive tie rod by investigating prevention and durability against its damage.

오늘날 자동차 기술의 비약적인 발전으로, 단순히 이동수단으로만 여겨왔던 자동차 는 과거와는 비교 할 수 없을 정도의 안전성과 편의성을 제공하고 있다. 이러한 편의 와 안전을 제공하는데 있어서의 핵심은 전자제어 장치의 발달로 이뤄진 결과이다. 최 근 개발되는 전자제어 장치는 통합 모듈제어의 형태를 지니고 있어서 설계의 복잡성 을 지니고 있다. 따라서 이러한 특성으로부터 발생되는 문제를 기존에 준수해왔던 IEC 61508으로는 해결하지 못해, ISO 26262가 제정되었다. 따라서, ISO 26262의 국내 도입 에 따른 발생되는 문제들이 예측되고 있다. 이러한 문제에 대한 분석을 통해, 모델 기 반 시스템공학 적용을 통해 해결하고자 노력하였다. ISO 26262의 국내 적용에 따른 가장 유려되는 개발 전체 라이프사이클에 안전성과 신뢰성을 만족하기 위한 개발 프 로세스 도입에 대한 문제와 요구사항 분석 및 개발, 그리고 관리 측면에 대해 시스템 공학 전산지원도구 활용을 통한 모델기반 시스템 공학 접근 방법을 활용한 방안에 관 하여 논의하고 있다. 본 연구 결과를 기반으로 향후 추가 연구를 수행하면, ISO26262 의 국내 자동차산업 도입에 따른 문제에 해결하기 위한 과정에 도움이 될 것으로 기 대된다.

In recent years, Prognostic Health Management (PHM) has caught the attention of lots of researchers in a wide range of applications. Thus, many researchers from research institutes, universities and companies have published and patented their findings in various fields of PHM. PHM is a method or technique that can be used to detect performance degradation and forecast remaining life of a system based on the health monitoring information. A number of review papers discussing on PHM methods and techniques have been presented by other researchers but mostly in maintenance of manufacturing equipments, aerospace systems and structural monitoring. This paper focuses on the trend and direction of PHM especially in the automotive industry through published research papers and also patents. The purpose of this paper is to recognize the trend and to provide suggestions for potential future research in PHM for automotive. Accordingly, this paper should offer opportunity for the manufacturers or researchers to get information on current trends and also potential areas that can be further explored in PHM for automotive.

This study analyzes lifes and damages at two automotive grills in use through the structural analyses with fatigue. As maximum equivalent stress in case of aftermarket grill frame becomes smaller more 15 times than horizontal grill frame, aftermarket grill is shown to be more stable. The lowest damage becomes 2968 in case of ‘SAE bracket history’ with the severest change of load at aftermarket grill. As it becomes smaller more 5 times than horizontal grill frame, aftermarket grill has more durability. Among the cases of nonuniform fatigue loads, ‘Sample history’ with the slowest change of load becomes most unstable in case of horizontal grill frame but ‘SAE bracket history’ with the severest change of load becomes most stable in case of aftermarket grill frame. The structural result of this study can be effectively utilized with the design of automotive grill frame by investigating prevention and durability against its damage.

The automotive speaker is modeld to nonlinear speaker model using the large signal performance measurement. In order to study the characteristics for the mass of cone paper and damper, the mass of the cone paper and damper is changed and the nonlinear parameters of the speaker are studied using the experimental approach. From measurement data, the effect on force factor, compliance(stiffness), resonance frequency, Q-factor is investigated by changing the conpaper and damper.

There has been a growing concern about the emissions of formaldehyde and VOCs from automotive interior materials which could have an important impact on the in-vehicle air quality(IVAQ) of automotive vehicles. Many leading automobile manufacturers have now introduced their own specification standards for testing and limiting emissions from products produced by their suppliers. In addition, ISO (International Standard Organization) has been established ISO 12219-1, 2, 3, 4, 5 to determine the emissions of volatile organic compounds from automotive vehicle. The objective of this paper is to compare the area specific emission rates determined from surface emissions testing using the microchamber(MC) in comparison with a 1 m³ emission test chamber(ETC) operated in accordance with ISO 12219-3, ISO 12219-4. Measured emission concentrations in absolute terms were different between Microchamber and 1 m³ chamber. However, qualitative comparison of the chromatograms shows that the Microchamber is able to perform a screening test

재제조는 사용 후 제품을 체계적으로 회수하여 분해, 세척, 검사, 보수조정, 재조립 등의 공정을 거쳐 원래의 성능을 유지할 수 있도록 만드는 과정이다. 자동차 교류발전기를 재제조하기 위해서는 재제조품에 요구되는 품질 및 신뢰성을 확실히 달성하기 위하여 공정 별 복잡한 작업들에 대하여 세부적인 사항들을 결정하고 이를 설계하는 일이 중요하다. 본 연구의 목적은 재제조를 위한 최적의 공정설계를 위해 FMEA를 활용한 체계적인 가이드라인을 제시하여 재제조품의