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During the vehicle lifecycle, customers are able to directly perceive the outer panel stiffness of vehicles in various environmental conditions. The outer panel stiffness is an important factor for customers to perceive the robustness of the vehicle. In the real test of outer panel stiffness after prototype production, evaluators manually press the outer panel in advance to identify vulnerable areas to be tested and evaluate the performance only in those area. However, when developing the outer panel stiffness performance using FEA (Finite Element Analysis) before releasing the drawing, it is not possible to filter out these areas, so the entire outer panel must be evaluated. This requires a significant amount of computing resources and manpower. In this study, an approach utilizing artificial intelligence was proposed to streamline the outer panel stiffness analysis and improve development reliability.

A crucial component utilized in the trunk space is the luggage board. Positioned at the bottom of the trunk, the trunk board separates the vehicle body from the interior and supports for luggage. The luggage board serves multiple functions, including load-bearing stiffness for luggage, partition structure functionality, noise insulation, and thermal insulation. There is a need for a competitive new luggage board manufacturing method to meet the increasing demand for luggage boards in response to the changing market environment. To address this, the "integrated sandwich molding method" is required. The integrated sandwich molding method utilizes three key methodologies: grouping processes to integrate similar functions, analyzing materials to replace them with suitable alternatives, and overcoming any lacking functionality through integrated design structures. This paper presents a methodology for developing the integrated sandwich molding method.

Even if an optimal design is produced in the mid-to-late stages of development, when the maturity of development is increasing, it is already difficult to accept the proposal between the organizations and functions. In case the optimal proposal is made with a small amount of information in the preceding stage, it will be helpful for mutual decision-making. In addition, if all members have a system and development environment that enables access and utilization of necessary data in a timely manner, it is possible to produce quick results through collaboration. To implement such a system and development environment, “digital modeling" of tangible and intangible assets will be essential and to implement an "integrated IT environment" that can access and utilize digital models. Until now, Hyundai Motor Company has not yet fully established a digital development environment that all researchers can simultaneously utilize during the concept development stage.

In this study, a novel selective matching logic for a wheel/tire is proposed, to decrease the vehicle driving vibration caused by wheel/tire non-uniformity. The new logic was validated through matching simulation/in-line matching evaluation. A theoretical radial force variation model was established by considering the theoretical model of the existing references and the wheel/tire assembly mechanism. The model was validated with ZF’s high-speed uniformity equipment, which is standard in the tire industry. The validity of the new matching logic was verified through matching simulation and mass production in-line evaluation. In conclusion, the novel logic presented herein was demonstrated to effectively decrease the radial force variation caused by the wheel/tire.

As data science technologies are being widely applied on various industries, the importance of data itself increased. A typical manufacturer company has a vast data set of products as 2D&3D drawing formats, but a common problem was that building a database from the 2D&3D drawings costs much, and it is hard to update the database after it once built. Also, it is high-cost job when the new factor researched and necessary to investigate the new factors on previously fixed or uploaded drawings. As new products are developed with time, these problems are getting more difficult. In this paper, an automated database building method using CATIA introduced and future probabilities are suggested. An aluminum wheel part was used as an example. An automated logic used CATIA V5’s VBA functions and was handled by python programming language.

In the era of electric vehicles(EVs), the need for weight reduction of the vehicle body is increasing in order to maximize the driving distance of the EV. Accordingly, there is an increasing need for research to efficiently apply lightweight materials, such as aluminum and CFRP, to the EV body parts. In this study, design methodologies and optimization measures to increase lightweight efficiency when applying lightweight materials to EVs will be discussed. Based on theoretical basis and basic performance of each part of the EV, the “Material Substitution Method” of replacing existing parts of a steel body with aluminum materials will be defined, and the optimal design process on how to overcome performance trade-off caused by material characteristics will be addressed. In applying the “Material Substitution Method” to the actual EV body design process, it was possible to convert 93% of the components from steel to aluminum and reduce the overall weight of the body by 23%.

As the AVN display in the car interior becomes larger and located above the center fascia, the driver's visual visibility is becoming important. In addition, since an expensive touch sensor is installed, a transparent electrode cost reduction technology for a display touch sensor that can replace an indium material, which is an expensive rare metal, is required. In this paper, we developed new transparent electrode materials and manufacturing methods for the touch sensor film which light reflectance is low and flexible without a separate low-reflection multi-layer, so that the design freedom is high and the material cost is low. By optimizing the amount of fluorine doping ratio in tin oxide, excellent electrical conductivity and high optical transmittance are secured, and the surface reflectance is reduced by adjusting the diameter and length of the silver nanowire. As a result, it was shown that the AVN display image and font readability was improved.

In this paper, an application process is studied at which the insertion loss (IL) test data of sound insulating parts or noise control treatments are utilized for the sound transmission loss (STL) simulation of the trimmed dash structure. The considered sound barrier assemblies were composed of a felt layer, a mass layer, and a decoupler layer. Flat samples of sound barrier assemblies with several different thicknesses were prepared, and ILs of them were measured by using a sound transmission loss facility. Flat samples were assumed to have mass-spring-mass resonance frequencies. The mass was set as the area mass of the sound barrier layer of the felt layer and the mass layer. The spring constant of the decoupler layer was assumed as the multiplication of that of an air spring and a spring correction factor.

Recently, automobile manufacturers are interested in the development of battery electric vehicle (BEV) having a longer mileage to satisfy customer needs. The BEV with high efficiency depends on the temperature of the electric components. Hence it is important to study the effect of the cooling system in electric vehicle in order to optimize efficiency and performance. In this study, we present a 1-D vehicle thermal management (VTM) simulation model. The individual vehicle subsystems were modeled including cooling, power electric (PE), mechanical, and control components. Each component was integrated into a single VTM model and it would be used to calculate energy transfer among electrical, thermal, and mechanical energy. As a result, this simulation model predicts a plenty of information including the state of each component such as temperature, energy consumption, and operating point about electric vehicle depending on driving cycles and environmental conditions.

For making metal touch feeling and lighting simultaneously, selective electroplating is widely applied in button, panel and etc. in interior/exterior parts of automotive. In this paper, new selective electroplating with printing are suggested as an alternative manufacturing process of two shot molding, PC (Polycarbonate) and ABS (Acrylonitrile-Butadiene-Styrene). Manufacturing process of selective electroplating with printing is as follows: For preventing to plate metal layer in area of letter or symbol, masking ink is printed on parts, button, panel, etc., with electroplatable PC+ABS. After conventional electroplating process, the part has electroplated metal layer except for the printed area. It had been studied the composition of ink and PC+ABS for obtaining skip plating and light transmittance on printed area.

The high speed continuous braking distance assessment is the worst condition for thermal fades. This study was conducted to investigate the relationship between fade characteristic and friction materials & brake fluid amount for improving braking distance. So, we used the dynamometer to measure the friction coefficient, braking distance and required brake fluid amount. Through the measurements, the research was carried out as follows. First of all, we studied the influence of friction coefficient about different shapes (chamfer shape, area of the friction material, number of slots) on the same friction material. Secondly, we knew the effects of braking distance by the shape of the friction material. Through these two studies, the shape of the friction material favorable to the fade characteristics was derived. Finally, we measured the amount of required brake fluid in caliper after 10 consecutive braking cycles through Dynamometer.

In the latest works [12], we presented the guideline for reducing Metal pick up(MPU, the main component of disc scoring) by controlling the location of the roughness of disc, the brake pad friction coefficients and the disc slot's size. In this study, the previously studied iron transfer theory to 'Cu free' brake pad and the disc surface roughness controlling methods which are based on the mass production manufacturing process are applied. It is possible to suggest the ways to improve the scoring-free disc without reducing friction coefficient between the disc and pad, and any demerit such as increased wear and airplane noise like conventional slot discs [11].

The friction properties related to squeal noise was analyzed with the development histories and simplified computational method. Firstly, the development histories were investigated especially focusing on the case which the friction materials were modified to improve squeal noise occurrence. Based on the histories, the friction properties of selected friction materials were newly measured using dynamometer. The average friction coefficient levels, torque oscillations, the increment of friction coefficient during full-stop, and etc. were compared with the squeal noise occurrence, and the results showed that increase of friction properties cause production of squeal noise. The result suggested that the size of friction energy was important factors related to triggering the squeal noise. Also, the contact conditions between rotor disc and friction materials were significant factors deciding the noise occurrence.

A signal lamp performs a function to inform the position and behavior of the vehicle. And it represents a specific design identity of the vehicle or brand identity. Recently it implements the unique three-dimensional effect while using a LED. However, a number of LEDs and complex form of the lens shape have to be applied, so results in the size, weight, cost increase. In this study, the hologram technology that is an exemplary technique for implementing the described three-dimensional image is applied. With a hologram, it is possible to reproduce a complex shape three-dimensional image by using a hologram film. Therefore the number of parts can be reduced. And it is possible to copy the film has a mass production benefits.

In the past few years, technological innovations in the automobile industry took vehicle performance to the next level. One such innovation is frame integrated panel door. This type of door helps automobile companies to have the advantages of both conventional panel and frame type doors. Though it has a good number of advantages, there are some drawbacks too. It requires improvements in its quality, NVH performance, weight and etc. Quality of a door is low due to the limitations in structural design and manufacturing technologies. And it is difficult to have a robust structure which leads to degradation of key performing factors such as NVH. For a lightweight vehicle, it is important to design an optimized structure for saving weight, without compromising its performance. In order to overcome these drawbacks a new optimized design structure is required for door system.

In recent years, the emerging technology competitions in automotive industry are improving engine efficiency and electronizing for coping with stringent fuel-economy regulations. However, fuel-economy technologies such as engine down-sizing and numerous electronic parts entrust burden plastic materials acing as mainly electric insulation and housing to have to be higher performance, especially temperature endurance. Engineering plastics (EPs) have critical limitations in terms of degradation by heat. Heat-resisting additives in EP are generally used to be anti-degradation as activating non-radical decomposition of peroxide. However, it could not be effective way to impede the degradation in long term heat aging over 1,000 hours at high temperature above 180 °C. In this study, we suggested the new solution called ‘shield effect’ that is purposeful oxidation at the surface and local crystallization of EP to stop prevent penetrating oxygen to inside of that.

This paper summarizes the development of a wireless message from infrastructure-to-vehicle (I2V) for safety applications based on Dedicated Short-Range Communications (DSRC) under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). During the development of the Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure (RSZW/LC) safety applications [1], the Basic Information Message (BIM) was developed to wirelessly transmit infrastructure-centric information. The Traveler Information Message (TIM) structure, as described in the SAE J2735, provides a mechanism for the infrastructure to issue and display in-vehicle signage of various types of advisory and road sign information. This approach, though effective in communicating traffic advisories, is limited by the type of information that can be broadcast from infrastructures.

The weight reduction of the car suspension parts has a direct influence on the ride and handling. However, the application of nonferrous metal materials, such as aluminum and magnesium, which results in a lighter weight of the suspension can lead to an increase in manufacturing costs compared to cast iron. In this study, vertical type high-pressure die casting using by electro-magnetic stirring (EMS) with A356 alloy in the sleeve was used to control the fine microstructure. Process optimization and part development, as well as unit product and automotive assessment were carried out for electro-magnetic stirring methods. Without making the slurry, the mechanical properties were obtained through optimization of process variables UTS 320MPa, YS 239MPa, EL 13.3%. It also succeeded in mass production with minimum cost increase of aluminum suspension components.

Hyundai's new engine is developed which optimize the cooling efficiency for knocking improvement and friction reduction. The cooling concepts for this purpose are 1) equalizing the temperature among cylinders by flow optimization, 2) cooling the required area intensively, 3) adopting ‘active flow control’ and 4) enlarging fuel economy at high speed range. In order to realize the cooling concept, 1) cross-flow, 2) compact water jacket & exhaust cooling, 3) flow control valve and 4) cylinder head with integrated exhaust manifold are considered. Improvement of knocking and friction reduction by increased cooling water temperature makes fuel efficiency possible. On the other hand, in order to strengthen the cooling around the combustion chamber and to reduce the deviation among the combustion chamber of cylinders, it is required to design the head water jacket shape accordingly.

This paper presents a transient vibration analysis of a nonlinear full-vehicle. The full-vehicle model consists of a powertrain, a trimmed body, a drive line, and front and rear suspensions with tires. It is driven by combustion forces and runs on a road surface. By performing time-domain simulation, it is possible to capture nonlinear behavior of a vehicle such as preload due to gravitational force, large deformation, and material nonlinearity which cannot be properly treated in the conventional steady state analysis. In constructing a full-vehicle, validation process is essential. Validation process is applied with respect to the assembling sequence. The validation starts with component levels such as tires, springs, shock absorbers, and a powertrain, and then the full-vehicle model is constructed. Model validation is done in two aspects; one is model accuracy and the other is model efficiency.