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The Design For Six Sigma (DFSS) process consists of four phases, identification & definition of opportunity, concept development, design optimization, and design verification. In the phase of concept development, TRIZ (Russian acronym for Theory of Inventive Problem Solving) is useful for creating new ideas from the present ideas, which includes the trimming strategy, the antidote strategy, and the picket fence strategy. In this paper, systems of a vehicle such as Variable Compression Ratio (VCR) engine, windshield wiper blade, and Continuously Variable Valve Actuation (CVVA) of engine, are selected and new concepts for each system are created by applying the previously mentioned three strategies. FMEA (Failure Mode and Effects Analysis), the latter part in the phase of concept development in DFSS, is conducted for newly generated concepts of systems that are mentioned above. As a result of FMEA, it is found that the wind lift of the wiper blade can be a serious problem.

The windshield is an integral part of almost every modern passenger car. Combined with current developments in the automotive industry such as electrification and the integration of lightweight material systems, the reduction of interior noise caused by stochastic and transient wind excitation is deemed to be an increasing challenge for future NVH measures. Active control systems have proven to be a viable alternative compared to traditional passive NVH measures in different areas. However, for windshield actuation there are neither comparative studies nor actually established actuation concepts available to the automotive industry. This paper illustrates a comparative conceptual study on windshield actuation for the active control of wind noise in a passenger car. Making use of an experimental modal analysis of the windshield installed in a medium-sized vehicle, a reduced order numerical simulation model is derived.

A new noble material for automotive bumper fascia has been developed by compounding of ethylene-propylene block copolymers with ethylene-α-olefin copolymers and some additives. Also mineral fillers are added, if necessary. This material is suitable for injection molding of large parts including automotive bumper fascia. By using selected rubbers which have proper melt viscosity, molecular weight, and co-monomer content, and adding modified polymer containing polar group, it has enhanced processibility and paintability maintaining general properties such as tensile strength, impact strength at low temperature, and thermal and UV stability. The remarkable characteristics of this material is good processibility compared to the conventional TPOs. This material has especially high melt flow index(20∼30g/10min at 230°C) and stable flow behavior at the processing conditions.

The purpose of the study is to investigate the ergonomic issues for control types and menu design types of in-vehicle information system (IVIS). The results showed that 1) linear-type controls with linear-type menu design had better performance 2) rotary-type control with rotary-type menu design had good subjective preference score 3) the performance and subjective preference of IVIS interface were strongly influenced by the compatibility between control types and menu design types of IVIS 4) there was a tendency that the performance of IVIS tasks was better when the display was located at higher level on center fascia. The results can be applied to develop a new control and menu design of IVIS from ergonomic view points.

The Rollover CAE model is developed for Rollover sensing algorithm in this paper. By using suggested CAE model, it is possible to make sensing data of rollover test matrix and these data can be used for calibration of rollover sensing algorithm. Developed vehicle model consists of three parts: a vehicle parts, an occupant parts and a ground boundary conditions. The vehicle parts include detailed suspension model and FE structure model. The occupant parts include ATD (anthropomorphic test device) male dummy and restraint systems: Curtain Airbag and Seat-Belt. We find analytical value of the suspension model through correlation with vehicle drop test, simulate this model under the conditions of untripped (Embankment, Corkscrew) and tripped (Curb-Trip, Soil-Trip) rollover scenarios. Comparison of the simulation and experimental data shows that the simulation results of suggested CAE model can be substituted for the experimental ones in calibration of rollover sensing algorithm.

In order to reduce total drag during aerodynamic optimization process of the passenger vehicle, induced drag should be minimized and pressure drag should be decreased by means of applying streamlined body shape. The reduction of wake area could decrease pressure drag, which was generated by boundary layer separation. The induced drag caused by rear axle lift and C-pillar vortex can be reduced by the employing of trunk lid edge and kick-up or an optimized rear spoiler. When a rear spoiler or kick-up shape was installed on the rear end of a sedan vehicle, drag was reduced but the wake area became larger. This contradiction cannot be explained by simply using Bernoulli’s principle with equal transit or longer path theory. Newtonian explanation with COANDA effect is adopted to explain this phenomenon. The relationships among COANDA effect, down wash, C-pillar vortex, rear axle lift and induced drag are explained.

Significant effort has been expended to improve the sound made by a closing car door. This study focuses on reducing door glass rattle sounds, not only evaluating the rattle influence of door glass support but also introducing an approach to reduce glass rattle noise by using sealing components. The first part of the study is dedicated to minimizing vibration. A jig is constructed to evaluate the influence of a door glass support on the rattling. The jig is employed so that the glass meshing between the A and B pillars can be controlled; the glass holder moves in the x- and z-directions and the belt molding moves in the y-direction. An impact hammer test was adopted for investigating door glass rattle. The frequency response obtained via impact hammer testing is analyzed by varying the glass support points and important factors that should be considered in early design stages are obtained. The second study is about optimizing vibration absorption.

This paper aims to evaluate the biofidelity of a human body FE model with abdominal obesity in terms of submarining behavior prediction, during a frontal crash event. In our previous study, a subject-specific FE model scaled from the 50th percentile Global Human Body Model Consortium (GHBMC) human model to the average physique of three female post mortem human subjects (PMHSs) with abdominal obesity was developed and tested its biofidelity under lap belt loading conditions ([1]). In this study frontal crash sled simulations of the scaled human model have been performed, and the biofidelity of the model has been evaluated. Crash conditions were given from the previous study ([2]), and included five low-speed and three high-speed sled tests with and without anti-submarining device.

In recent years, pedestrian protection from passenger car impacts has become an important issue. In this study, a lower stiffener system has been implemented in order to reduce lower leg injuries. This system was developed using finite element analyses and impact testing. Injury criteria including bending angle, shear displacement, and deflection were studied in the analyses. These variables were optimized using a DOE (Design of Experiments) sensitivity analysis.

A practical application of the Target Cascading scheme for the development of the front bumper system of a passenger car is investigated in this paper. The Target cascading in the crash performance of vehicle developments requires a systematic approach, propagating from the desired vehicle-level performance target to appropriate specifications in a system- and/or component-level. To define the values of design specification in the front bumper system, three physical variables are derived by analyzing the vehicle-level performance of the frontal impact under the high-speed (56kph NCAP frontal impact) and the low-speed (15kph RCAR structural test) crash conditions. To ensure the sequential deformation in the high-speed frontal impact and to minimize the damage of the structural member in the low-speed crash, the maximum collapse load of a crash box should be smaller than the collapse load of a front side member.

In order to utilize in-vehicle systems efficiently, many vehicles are becoming equipped with integrated controls near the center fascia or the control box. However, the placement of these control systems can cause safety issues and risks due to visual distractions. In this study, we proposed a new integrated touch screen on the steering wheel. For this experiment, a control system was placed on the steering wheel or the center fascia. 15 participants were required to drive while utilizing vent and navigation control tasks regarding four different locations. Three of these locations were based on the steering wheel (center, upper right, lower right) and one location on the center fascia. Afterwards, the task completion time and visual distraction rate of the different locations were measured and compared. The results showed that a touch screen placed on the upper right section of the steering wheel had better performance and lower user discomfort.

This study presents a design methodology to predict the crash behavior of mid-size sedan with a simplified crash model. Without detailed conventional finite element, the simplified crash model can be adopted in the early stage of the vehicle design. Designing vehicle structure to satisfy crash performance target is highly complex problem in the early design stage, because of the nonlinear mechanical behavior, high number of degrees-of-freedom, lack of information and boundary conditions changing over the following development process. In this study, the front structure of the vehicle is divided into load-carrying members and the rigid element through the analysis of load-carrying mechanism, and its physical property (force-displacement relation) is parameterized as the property of the non-linear discrete beam element of the LS-DYNA. The effectiveness of the proposed research is shown by the example of the mid-size sedan.

‘Active safety systems’ are actively being developed to prevent collisions. The integration of ‘active safety systems’ and traditional ‘passive safety systems’ such as seatbelt and airbags is an important issue. The ‘Integrated safety’ performance is that comprehensively controls the performance of ‘active’ and ‘passive’ safety systems to reduce occupant injuries. To develop ‘integrated safety’ performance, it is important to develop crash scenarios for autonomous vehicles. This study is about the development of ‘Estimation Tool of Occupant Injury Risk’ for deriving risk integrated safety scenarios focused on occupant injury. The results of random traffic simulation using ‘Virtual Prototype’ were used to select parameters, and ‘MADYMO Equivalent Simplified Vehicle Crash Analysis Model’ was used to derive F-D characteristics for each vehicle collision condition.

Bad weather conditions such as torrential rain, heavy snow, and thick fog frequently occur worldwide. Vehicle accidents in such bad weather conditions account for a significant portion of all vehicle accidents, and the level of damage is relatively severe compared to other accidents that occur in clear weather. This paper analyzes the driver's driving stability in bad weather conditions, which has such a significant meaning, in various ways through experiments on the inconvenience experienced by the driver. In this study, three levels of bad weather conditions were implemented in a driving simulator environment to evaluate driver inconvenience for six activities. Through driving experiment, quantitative bio-signals and vehicle signals were analyzed in each weather condition. The SD survey was used to assess the driver's inconvenience level for activities performed while driving and analyze the ranking of inconvenience.

To achieve a mass goal and minimize the bell mouthing phenomenon of Passenger Air Bag Housing which takes place when the air bag is in explosive action and detrimental to the safety of passenger side because excessive canister bell mouthing may distort and crash the top surface of instrument panel, a study on the replacing process of a PAB housing to a different material and process was performed. The explosive action of current steel PAB housing was firstly analized to evaluate the reaction forces transferred through the PAB and find out the adaptable material for replacing process. Due to the properties among the die casting alloys, the AM60B alloy was chosen for our new material for PAB housing. Then, stress analysis by the finite element method was performed for a design modification of magnesium one piece housing.

In contrast to the other types of crash simulation, integrated analysis is needed to perform the side impact simulation, and the acquired injury values are so sensitive that they are difficult to assess by the deformed vehicle structure itself. Therefore, the accurate FE side impact dummy (US-SID, Euro-SID) models are needed to predict the various injury values in side impact simulation. In the past, rigid body model or coarse FE model have been used. The advantage of these models is low computing power, but they have lack of predictability especially in the high-speed crash analysis such as NCAP and car-to-car simulations. The deviations are caused by inaccurate geometry and improper material characteristic expression of the side impact dummy models. In this paper, the development of new side impact dummy models and their applications at full car simulations are introduced. Also, the analyses about injury values are illustrated in side impact simulation.

There are some problems “windows fog up a lot” for ventilation system. We have Test Development Procedure to prevent the fog problems. But, Many fog problems occurred in the cars that we made. So in this paper, new ventilation system is needed and developed. The Smart Ventilation System automatically controls indoor air quality even though the blower motor is off. There are two sensors that is used for AutoDefogSensor system and CO2 CONTROL system.. The sensor is on when blower motor and heater control is off. We use these signals and make new ventilation logics. We evaluate this system in chamber & '13 winter test in USA.

In order to reduce the cost and weight of the soft-foamed instrument-panel (IP), we developed the new IP which is made by the 2 kinds of injection methods. One is the compression-injection with back-foamed foil inserted, and the other is two-shot injection with the passenger-side airbag (PAB) door. We named it ‘IMX-IP’ which means that all components (‘X’) of the IP with different resins are made In a Mold. The development procedure of this technology was introduced (1) Design of the new injection mold through TRIZ application, (2) Optimization of the injection conditions and back foamed-foil for minimizing the foam loss and thickness deviation, (3) Development of CAE method for two-shot injection compression, (4) Reliability performance test and application to the mass production. The reduction of the processes through the two-shot molding with back foamed-foil inserted made it possible to enhance soft feeling on IP and reduce the cost and weight simultaneously.

Recently, the design of automotive headlamps has become diversified and complicated according to customer needs. Hence, structural complexity of the headlamps has also increased. Complex structure of the headlamps inevitably causes a disturbance in air circulation. For this reason, inadvertent micro-sized water droplets, called fogging, are condensed on the inner surface of headlamp lens due to temperature difference between the inner and outer lens surfaces. To circumvent fogging inside of the headlamp lens, an anti-fogging coating is indispensable. Conventionally, diverse surfactants have been adopted as substantial material for the anti-fogging coating. However, the usage of the surfactants causes undesirable side effect such as water mark arising from vapor condensation, which is an important issue that must be fully resolved. In this study, we developed an innovative anti-fogging coating material without using conventional surfactant.

In this paper, we focused on the robust wiping performance of high speed driven condition as an important situation for vehicle safety. Frist, we selected appropriate wiper performance parameter to accurately predict its ability not only systematic point but also vehicle point. Second, we obtained parameter sensitivity of wiper high-speed performance using DFSS technique. Third, we developed prediction and optimization tool using commercial program; Excel and Visual Basic. Finally, we improved our tool to compare vehicle test and then modified prediction coefficient for the accuracy of tool. Thus, we proposed a systematic tool to predict wiping performance in high speed vehicle, and successfully obtained efficiency when we developed the new project’s wiper performance.