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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.

This paper presents the research related to the self-driving system that has been actively carried out recently. Previous studies have been limited to ensure the path following performance in linear and steady state-alike handling region with small lateral acceleration. However, in the high speed driving, the vehicle cornering response is extended to nonlinear region where tire grips are saturated. This requires a technology to create the driving path for minimum time maneuvering while grasping the tire grip limits of the vehicle in real time. The entire controller consists of three stages-hierarchy: The target motion is determined in the supervisor phase, and the target force to follow the target behavior is calculated in the upper stage controller. Finally, the lower stage controller calculates the actuator phase control input corresponding to the target force.

Automotive companies are trying to enhance the customer’s impression by improving engine sound quality. The target of this sound quality is to create a brand sound that is preferred by their customers as well as quietness of interior noise. Over the past decade there have been many studies in the field of automotive sound quality. These have included the technologies such as tuning of intake orifice and exhaust orifice, tuning of structure-borne, intake feedback devices, active exhaust valves, ANC (Active Noise Cancellation) and ASD (Active Sound Design). The three elements of the sound that affect the feeling of the customer are known as engine order arrangement, frequency balance, and linearity. Here, the most important thing in sound quality development is the order arrangement.

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.

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.

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.

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.

To date, efforts to improve occupant protection in side impact crashes have concentrated on reducing the injuries to occupants seated on the struck side of the vehicle arising from contact with the intruding side structure and/or external objects. Crash investigations indicate that occupants on the struck side of a vehicle may also be injured by contact with an adjacent occupant in the same seating row. Anecdotal information suggests that the injury consequences of occupant-to-occupant impacts can be severe, and sometimes life threatening. Occupant-to-occupant impacts leave little evidence in the vehicle, and hence these impacts can be difficult for crash investigators to detect and may be underreported. The objective of this study was to evaluate the risk of impact injury from occupant-to-occupant impacts in side impact vehicle crashes. The study examined 9608 crashes extracted from NASS/CDS 1993-2006 to investigate the risk of occupant-to-occupant impacts.

A new heat-resistant cast iron alloy has been developed for the exhaust manifolds of new passenger-car diesel engines. This development occurred because operating demands on exhaust manifolds have increased significantly over the past decade. These demands are due to higher exhaust gas temperatures resulting from tighter emission requirements, improved fuel efficiencies, and designs for higher specific engine power. These factors have led to much higher elevated temperature strength and oxidation resistance requirements on exhaust manifold alloys. Additionally, thermal fatigue that occurs directly as a result of thermal expansions and mechanical constraint has become an increasingly important issue. The research detailed in this paper focused on the optimization of the chemical composition of a Si-Mo ductile iron to improve the mechanical and physical properties for use in an engine exhaust manifold.

In order to perform the Optimal Route Planning avoiding traffic congestion, the structural elements (Rode type, Link type, Facilities type, Lane number, Turning type) in digital map and real-time traffic information are required. However, subjectively tuned cost weights of these elements, non theoretical relationship, and partially supported real-time traffic information that are mostly used for this implementation are not enough to satisfy. Therefore, in this research, by analyzing the relationship between the previously acquired traffic information history for some period of time and elements in digital map, we introduce the reasonable traffic information model that makes to estimate the speed information. Including the estimated speed, all the important factors of map database and the driver's preference, finally we made the cost model.

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.

The purpose of this paper is an attempt to make a good compromise between ride and handling without deteriorating each other. Compromise between ride and handling has been a problem for suspension designer. Attempts are made by varing suspension parameters. Effects of each combination has been tested with basic ride and handling test methods. For ride to maintain a constant natural frequency through all load range was a primary target. And for handling to get adequate roll angle at 0.5g lateral acceleration was a target. In conclusion, combination of polyurethane suspension bump and normal rear spring was proved to be able to provide the best compromise, low cost, light weight and better performance. This also showed polyurethane bumper could carry out spring aids successfully.