This paper describes a development of the Hybrid III AM 50%ile dummy FE model to be used for frontal impact simulations. The precise geometries of the dummy were measured at a pitch of 1.0 mm using X-ray CT scans. The material properties and the mechanical responses of the components were measured in static and dynamic tests and were used for the model validation. The FE model showed a good correlation when compared the kinematics and injury index values to those in the sled impact test.

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Planetary gear type of torque - sensing Limited Slip Differential(LSD) is discussed in this paper. The gear type torque-sensing LSD is required not only to prevent stick-slip but also to slide smoothly between the contact surfaces. For this matter, we focus on roughness on the sliding surfaces of the planetary gear circumference. Applying the roughness to the sliding surfaces makes it possible to acquire stable frictional characteristic. Besides, a theoretical study for the frictional characteristic noted above is feasible instead of testing actual units by using mixed lubrication analysis which models the roughness of the planetary gear circumference. In addition, applying carbon based hard coating to the planetary gear contributes to the acquirement of durability against abrasion and seizure which are opposite to roughness.

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A HCCI engine control was investigated for a natural gas co-generation system. A 4-cycle 2-cylinder engine was used for HCCI combustion as a test engine. The HCCI engine operations with the spark ignition were controlled by actuating the throttle valve and the fuel valve at a constant intake temperature using an electric heater. The throttle valve position was controlled due to keeping a constant engine speed. The fuel valve position and the ignition timing were controlled by referring their value maps preserved in the engine control unit for the engine speed and the intake pressure. The system was conventional, but cheaper and simpler than those of previous proposals for HCCI control. The control system was successful for HCCI stable control when the engine load changed from start to the rated power.

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The engine system concepts that can correspond to obtainable low-cost liquid fuel by the fuel market in the future have been researched. To use multiple liquid fuels, a system which utilizes diffusion compression ignition combustion combined with the HEV is proposed. The combustion characteristics of diesel fuel and regular gasoline were clarified by combustion visualization. After warming-up of the engine, the possibility that the regular gasoline, the diesel fuel, and the mixing fuel of them were able to be used for this system was confirmed.

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The Urea SCR system is one of the most promising exhaust NOx aftertreatment systems. However, it tends to suffer from very low NOx conversion efficiencies under low exhaust gas temperature and high GHSV conditions. To overcome this tendency, we have introduced a dual type SCR system consisting of a close-coupled one and main one located before and after the particulate filter, respectively. The rest results have shown that the close-coupled SCR catalyst can effectively reduce NOx at light load and during warm-up, resulting in complying with future stringent NOx emission standards proposed in both Japan and the E.U.

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This paper describes the influence of multi-antioxidants addition in biodiesel fuel on storage stability. In experiment, several phenolic and amine antioxidants mixture were evaluated by the method based on ASTM D4625 storage stability method for 6 months. The experimental results show that the combination of phenolic and amine gives the synergy effect on suppression of peroxide production, and high oxidation stability and long peroxide induction period of biodiesel fuel in Rancimat test were shown in experiments at long-storage period.

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The following two vehicle fire tests were conducted to investigate the fire spreading to an adjacent vehicle when the Pressure relief device (PRD) of the fuel-cell vehicle was activated. A) Fire test involving adjacent gasoline vehicle. B) Fire test involving three adjacent fuel-cell vehicles assuming ship transportation. The test results indicated that the adjacent vehicles were ignited by burning interior and exterior materials of the fire source vehicle, but that the hydrogen flame produced by the activated PRD was not a factor.

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Toyota Motor Corporation has been developing the fuel cell hybrid vehicle and continuing various approaches for mass production. In this study, some of mass transfer in the reaction field such as oxygen transport, water drainage, and electronic conductivity were quantitatively observed by using new methods. The obtained results could be applied to design requirements for an ideal reaction field, and also brought promising prospect to achieve the fuel cell miniaturization.

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Characteristics joining of dissimilar metals, for in this case aluminum alloy and steel sheet, were evaluated by using new developed aluminum filler wire in MIG braze-welding and laser braze-welding. The jointing mechanisms of dissimilar metal joints were studied from the perspectives of the interface between aluminum alloy and steel. This paper also included results of evaluation for the durability of the joint corrosion resistance and quality of aluminum alloy/steel hybrid parts.

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The fuel cost improvement by reducing the car weight is strongly required for heat-trapping gas (CO₂) reduction. In this study, the possibility of lightening of car components that received bending and compressive load was investigated with use of aluminum alloy/steel hybrid structure. It is found that higher performance per weight can be achieved with the hybrid structure compared with a conventional structure using a single material. In the present case, the best material arrangement is to set the aluminum alloy on the compression side and the steel on the tension side.

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Vehicle-infrastructure cooperative safe driving support systems are able to provide drivers with information about dangerous situations beyond their field of view. When many systems are familiarized in traffic situation, some different messages from them may be provided drivers at the same time. In this case, human machine interface is very important matters not to confuse drivers in getting the messages from the systems. This study is aimed to suggest some ideas of designing visual and auditory displays to present drivers two messages adequately when two different systems work at the same time. The driving simulator experiments were carried out to accomplish this aim. The results showed that visual and auditory displays based on priority of messages were useful for reducing total glance time to the visual displays and lateral displacement of vehicle. The results also showed that if concerned message had vanished although the dangerous situations had existed, it gave rise to drivers' misunderstanding and an inadequate driving behaviour. According to those results, it is necessary to consider the traffic situation where some systems work simultaneously in order to design better visual and auditory displays and reduce drivers' misunderstanding.

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To design a legible text on a multi information display (MID), readability of the text typography, such as character style, character distance and line space were examined by a reading task. The sentence of the reading object on the display was indicated intermittently, that was simulated driver's behavior to watch the MID while driving, and the time-length to read was measured. After the experiment, subjective comparative evaluation of impression to text typography was performed. The readability of a contextual sentence and meaningless texts were compared, and an influence of different text typography on the readability was examined.

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We have constructed a design review system in which Full Process and Quick design review processes are selectively used according to the degree of newness in a design change. The Quick Design Review uses a Change list and Design Review Based on Failure Mode (DRBFM) worksheets to focus on the changed points. This method enables the engineers involved to identify problems and to devise solutions efficiently and effectively through discussions. This paper describes the development of Quick Design Review process including actual application examples.

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