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Recently safety systems for the commercial vehicle have been rapidly developed. However, we still have many problems in the vehicle stability and the braking performance. Especially, a commercial vehicle may meet a dangerous braking condition when the vehicle is lightly loaded or empty and when the road is wet or slippery. Under these conditions, the truck can spin out or the tractor can jackknife or the trailer can swing out. To design the air brake system for the commercial vehicle, since the air brake system has many design variables, there must have been intensive researches on a method how to prevent dynamic instability and how to maximize vehicle deceleration. In this study, mathematical models of the tractor-semitrailer and the air brake system including an ABS controller have been constructed for computer simulation. Also, simple examples are applied to show the usefulness of the program.

Interior parts that are composed of plastic usually deform under various temperature conditions. It is necessary to obtain the material properties for an analysis of the thermal deformation under the heat cycle test. Specifically, creep data of plastic material was introduced for studying the time-dependent deformational behavior of the pillar trim in the heat cycle test. The time-hardening version of the power-law creep model was applied to account for the permanent deformation following the heat cycle test, which was verified through a comparison of the test results with the result of finite-element analysis for a simple model. In this study, a methodology was developed for the optimal design of the A-pillar trim in terms of the positions of the mounts. The analyzed results were used to approximate a function that was constructed by the response-surface method. Design procedures were repeated to minimize the thermal deformation at the areas of interest.

A large study of rear-end collisions was conducted for the neck injury indicators and test procedures. Neck injury in low-speed rear-end collisions is a big issue because there are a lot of patients despite low-speed rear-end collisions. Europe, Korea and Japan introduced the specific part in the New Car Assessment Program to reduce whiplash injury in low-speed rear-end collisions. From the legal point of view, to reduce the frequency and severity of injuries caused by rearward displacement of the head in rear-end collision, USA, EC, Korea, Japan and others internationally cooperated to make the global technical regulation (GTR) in UNECE/WP29. In 2008, after much meandering, GTR No. 7 head restraints were established. However the GTR No.7 is not a unique regulation because many countries had their own opinions and domestic regulations, and many questions related to injury criteria and biomechanical issues of dummy remain unresolved.

The noise of interior plastic parts has been one of the major driving factors in the design of automotive interior assemblies. This phenomenon is one of the major contributors to the perceived quality in a vehicle. The noise is caused by interior plastic parts and other parts as a result of permanent deformation. Traditionally, noise issues have been identified and rectified through extensive hardware testing. However, to reduce the product development cycle and minimize the number of costly hardware builds, hardware testing must rely on engineering analysis and upfront simulation in the design cycle. In this paper, an analytical study to reduce permanent deformation in a cockpit module is presented. The analytical investigation utilizes a novel and practical methodology, which is implemented through the software tools, ABAQUS and iSight, for the identification and minimization of permanent deformation.

In this study, design procedure and performance of a series-parallel type plug-in hybrid electric vehicle (PHEV) are investigated using the virtual integrated development environment (VIDE). First, the powertrain model of the target PHEV is constructed using the provided component library in the VIDE. Component parameters are determined based on the objective vehicle performance such as the maximum speed, hill climbing ability, acceleration performance etc. In addition, control algorithm and a full car simulator are developed for the target PHEV. The VIDE full car simulator is validated by AVL CRUISE software. Using the VIDE simulator, performance of the PHEV component and mode control algorithm are investigated and modifications on design parameters and mode control algorithm are proposed to improve the fuel economy.