Search Results

For the robust passenger NCAP(New Car Assessment Program) 5star and the stable neck injury performance, a new concept of passenger airbag has been required. Especially, the deployment stability and the vent hole control technology of the passenger airbag can be improved. According to these requirements, the deployment stability technique has been studied and the ‘Active Vent’ technology has been developed. As a result, these technologies have led to achieve the robust NCAP rating and are applied to the production vehicles.

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.

During a new vehicle development process, there are several requirements for side impact test that should be confirmed. One of the requirements is the prevention of door opening during side impact test. Even though there are many causes for door opening problem, this study deals with inertia effect by impact energy. Until now, there have been two classical methods to prevent car door from opening in side impact. One is the increment of the inertia resistance by increasing the mass of the balance weight and the spring force. The other is the application of the blocking lever. Unfortunately, in spite of our efforts, the door opening problem occurs occasionally. Therefore, to improve the problem fundamentally, this paper proposes a new blocking lever mechanism that work similar to ball-point pen structure. The proposed mechanism fixes the blocking lever when the opening directional inertia force is applied to the door outside handle during side crash.

The purpose of this study is to develop a dynamic model that can accurately predict the motion of the door handle and counterweight during side impact crash tests. The door locking system, mainly composed of the door outside handle and door latch, is theoretically modeled, and it is assumed that the door outer panel can rotate and translate in all three directions during a side impact crash. Additionally, the numerical results are compared with real crash video footage, and satisfactory qualitative agreement is found. Finally, the simplified test rig that efficiently reflects the real crash test is introduced, and its operation is analyzed.

‘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.

With the recent development of technologies for interpreting vibration and noise of vehicles, it has become possible for carmakers to reduce idle vibration and driving noise in the phase of preceding development. Thus, the issue of noise generation is drawing keen attention from production of prototype car through mass-production development. J. D. Power has surveyed the levels of customer satisfaction with all vehicles sold in the U.S. market and released the Initial Quality Study (IQS) index. As a growing number of emotional quality-related items are added to the IQS evaluation index, it is necessary to secure a sufficiently high quality level of low-frequency speaker sound against rattle noise. It is required to make a preceding review on the package tray panel, which is located at the bottom of the rear glass where the woofer speakers of a passenger sedan are installed, the door module panel in which the door speakers are built.

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.

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.

The fuel economy of a vehicle can be improved by recuperating the kinetic energy when the vehicle is decelerated. However, if there is no electrical traction component, the recuperated energy can be used only by the other electrical systems of the vehicle. Thus, the fuel economy improvement can be maximized by balancing the recuperated energy and the consumed energy. Also, suitable alternator and battery management is required to maximize the fuel economy. This paper describes a design optimization process of the alternator and battery system equipped with recuperation control algorithms for a mid-sized sedan based on the fuel economy and system cost. A vehicle model using AVL Cruise is developed for cycle simulations and validated with experimental data. The validated model is used for the parametric study and design optimization of the alternator and battery systems with single and dual energy storage.

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.

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.

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.

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 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.

Hyundai Motor Company developed its second-generation fuel cell hybrid electric vehicle (FCEV) based on its small Tucson SUV. Compared to Hyundai's first generation fuel cell vehicle, the Santa Fe FCEV, the Tucson FCEV has an extended driving range plus cold weather starting capability. It incorporates numerous technical advances including a fuel cell that operates at sub-zero temperatures and a new high voltage lithium ion polymer battery. Using both a fuel cell and a high voltage battery as sources for driving energy, the Tucson hybrid system provides optimum driving conditions, which ensures high tank to wheel efficiency. The Tucson FCEV's power plant has been located in the front - under the front hood - unlike its predecessor Santa Fe FCEV, which featured an under-floor installation. More importantly, Tucson FCEV's driving range has been extended to 300km thanks to its 152-liter hydrogen storage tanks.

A module based IPS (Intelligent Power Switch) evaluation system is proposed in this paper. As the IPS is gradually replacing the conventional relay and fuses, the stability and reliability of power system depends more on these IPS. The proposed IPS evaluation system outperforms the conventional manual evaluation in terms of speed and efficiency. This paper will introduce the structure of hardware and software of the IPS evaluation system. The system is placed between the module and cable connector to evaluate the module in an operating car without changing the cables. The control and signal processing is carried out by personal computer which is connected to the evaluation system by USB (Universal Serial Bus). The load resistance can be switch from actual load to arbitrary value using relay circuitry and DC electric load controlled by GPIB (General Purpose Interface Bus). CAN (Controller Area Network) circuits were added to control the IPS mounted inside the module.

An important trend among vehicle NVH engineers is the production of attractive engine acceleration sound quality for the enhancement of a vehicle's image and performance. In addition, customers have increasing interest and enjoyment in customizing their cars to reflect their personal taste and preferences. The PESS (Personalized Engine Sound System) has been developed for making a unique and individually customizable vehicle concept. The system allows the customers an opportunity to create a variety of engine sounds in a single vehicle using active sound design technology. In this system, three different engine sound concepts are pre-defined, Dynamic, Sporty, and Extreme. Each of the engine sounds can then be adjusted with parameters that determine the timbre, such as main order, rumble, and high order. In addition, the pedal position during acceleration has also been used as a parameter to further personalize the experience.

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.

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.