In recent years, the use of computer simulation in design development to assess vehicle performance has become widespread. This was caused by a remarkable innovation in both software development as well as hardware performance that not only helped in improving the accuracy of simulation but also improved the turnaround time sufficiently to enable a shorter vehicle development period.

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A measuring method has been developed that can measure the liquid fuel (= wall-wet) quantity in an intake port and a cylinder under transient states. This method uses a specified single-cylinder research engine with a rapid valve train shutdown system for maintaining the wall-wet condition after it occurs and a transient state engine speed control that uses a low-inertia dynamo. This paper clarified the ratio of injected fuel at the 1^st cycle from cold start (intake port wall-wet: 64%, cylinder wall-wet: 24%, burned fuel: 12%), and the increasing transition of these wet quantities cycle by cycle.

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One of the authors has found that the thermal ignition of hydrocarbons is controlled by a reaction loop initiated by the decomposition of H₂O₂, and proposed a universal rule describing the hydrocarbon ignition process. The universal rule was applied to answer the question "What is X in the Livengood-Wu Integral?", and to clarify the dependence of ignition delay times on pressure. X is basically the heat accumulated in the induction time of thermal ignition. However, CO satisfies the necessary condition of X because the formation rate of CO is proportional to the heat generation rate.

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Facings, ring shape frictional disk for automobile dry clutch are fabricated by using glass yarns while resin is used as the matrix in conjunction with some filler. In order to assure the durability of a prototype facing at severe conditions, a spin-burst strength can be well in obliged where the facing disk is rotating at higher than 10000 r/min. The purpose of this study is to show how much accurately we can predict the spin-burst strength of facing disks based on the tensile strength of the material, and to discover a factor effective in order to raise spin-burst strength.

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Owing to its flat-shaped combustion chambers, the combustion characteristics of rotary engines (RE) are quite different from those of ordinary reciprocating gasoline engines. In this paper, in order to gain a better understanding of RE combustion, ignition and flame propagation were observed in detail using visualization apparatus such as an optical RE and a rapid compression machine. Furthermore, this development focused on achieving faster RE combustion for reducing CO2 emissions. Combustion simulation, visualization, and dynamometer tests were conducted. As a result, the optimal spark plug arrangement leading to high thermal efficiency was identified.

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The disc wheels of cars have evolved with the development of steel, aluminum, and magnesium materials. For further development, this paper introduces an outline of the possibility of weight reduction and the issues for practical use by making trial full carbon composite disc wheels.

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It had been demonstrated that the fatigue life of hot forging dies for connecting rods was improved by cavitation peening (CP). In the present paper, in order to improve peening intensity and identify CP surface modification, the changes in Vickers hardness, surface roughness and residual stress were measured in terms of their depth within a specimen made of alloy tool steel peened by CP. It was demonstrated that peening intensity improved in comparison with shot peening (SP) and the former type of CP, and that residual stress in the sub-surface changed according to CP processing time.

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This report systematically discusses normal driver avoidance behavior for when pedestrians are. Factors that influence driver's avoidance behavior were identified by observing real traffic situations. Factors that significantly influence behavior were selected through driving simulator tests based on experimental design. The way in which each factor influences behavior was clarified. The sequence of a driver's avoidance behavior is as follows: the driver predicts a danger to the pedestrian and releases the accelerator, then, the driver judges danger and presses the brake, finally, the driver presses the accelerator after confirming that the pedestrian has gone out of the lane.

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Position information of the vanishing point is necessary to estimate 3D information using optical flow of images obtained from an onboard vehicle camera. However, the vanishing point does not exist when the host vehicle turns. Therefore, in this paper, we propose a new method for estimating the 3D information in which the vanishing point is not used by extracting the optical flow in each area classified into vehicles, the road surface, and the background regions.

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We propose an original evaluation method for estimating workload of operating In-Vehicle system focused on brain resource. An original index (spare mental capacity) is compared with vehicle behavior, subjective appraisal, and occlusion method. The validity of this evaluation method is verified in this paper.

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This study investigated the perception mechanism of a flat ride during highway driving. A flat ride is treated here as a comprehensive ride comfort perception consisting of a floating feeling, a body tossing feeling and other sensations induced by low-frequency oscillations. In this study, vehicle motion was measured using a GPS receiver and an inertial navigation system. The driver's head motion relative to the vehicle was measured with a motion capture system consisting of cameras attached to the vehicle. Absolute head motion with six degrees of freedom in space was calculated by using the measured motion data. The results of an analysis showed that a flat ride could be quantified based on the amount of absolute head motion. Laboratory tests were also conducted to investigate the effects of motion in the visual field on the perception of ride comfort. The experimental results showed that perceptions of even the same motion varied depending on the visual conditions, such as the location of the hood and instrument cluster. It was found that such differences in motion perception affected the evaluation of a flat ride.

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This paper proposes deceleration for collision avoidance (DCA) as a new index to evaluate collision risk against forward obstacles. Cases in which the vehicle in front maintains its current acceleration or decelerates abruptly are defined as overt- and potential DCAs, respectively. Numerical simulations are performed to compare the DCA values with time-to-collision and margin-to-collision, which are wellknown indices used to evaluate the potential collision risk in a situation where the possibility of collision with a forward obstacle is high.

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This paper proposes a method to provide a forward obstacle collision warning system (FOCWS) based on deceleration for collision avoidance (DCA) proposed in the first report. First, driving simulator experiments are performed to determine reaction time, which is an essential parameter for the calculation of the index. Next, we propose a new FOCWS that provides drivers with a real-time indicator of DCA as visual information in addition to a warning sound as auditory information. Driving simulator experiments are conducted to verify the effectiveness and acceptability of the proposed system.

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A total stamping simulation system, which enables the advanced study of the formability of stamping parts and the accuracy of assembled parts, has been developed. It can be applied from the vehicle-body-parts design phase to the production preparation phase. The developed system consists of 1) simulation technologies to enable parts designers to evaluate the function and formability of a part, 2) simulation technologies to predict the dimensions of stamping parts with high precision and 3) simulation technologies to obtain parts with high dimensional accuracy after the connection of stamping parts by hemming. The system can be used to drastically reduce the vehicle development period without reducing the dimensional accuracy of parts.

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The time differential GPS is capable of measuring high-accuracy ground velocity. However, this measuring system can't measure the velocity during GPS integrity error.To interpolate the GPS integrity error period with velocity by acceleration integration, using Doppler velocity, we have developed a high-accuracy speedometer which restricts the acceleration integration error without being affected by road surface conditions as well as the GPS integrity error.

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The study aims to calssify older drivers in order to clarify their driving behavior. These classification approach will help us to understand their characteristics as well as to develop driver assistance systems and education programs in order to prevent trafic accidents. We focused on three aspects of drivers, collision avoidance, general driving and driving style. We first applied cluster analysis to driver parameters gained by driving simulator and questionnaire studies. The result classified subjects into several clusters. We then carried out linear discriminant analysis to describe linear discriminant functions. Using the fucntions, we can classify them with high probability. Evaluation of functions also showed characteristics of each cluster.

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A new clean 2.0L L4 DI diesel engine, called the M9R engine, has been developed. This engine achieves the best performance in its class by the use of new technologies (e.g. piezo-driven type injectors) and meets the targets of the new Japanese emissions regulations (Post New Long Term: PNLT) with the successful application of a Lean NOx Trap (LNT) catalyst, a world's first for a diesel engine. This paper introduces an outline of the M9R engine and its performance.

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