It is necessary for realization of comfortable cabin to achieve target spectrum of roadnoise. For this achievement, the authors specify seven eigenvalue of tire and clarify ideal eigenvalue according to combination of tire with suspension. This paper shows it is possible to control each tire eigenvalue with new tire analysis model and optimization technology.

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A flexible legform impactor will be introduced to JNCAP in 2010. The purpose of this study is to verify the flexible legform impactor kinematics and mechanical responses to those of the TRL impactor in the car front impact. The flexible legform impactor FE model used in this study was developed using reverse engineering technology based on X-ray diffraction. The impact kinematics and the mechanical responses were compared with the test results.

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The study examined the test condition for the pedestrian lower leg protection using a Flex impactor FE model. The effects of the impactor height and an additional mass were discussed comparing the kinematics and responses to those of a human FE model. The results showed that the impactor at a height of 75 mm from the ground generates closer moment and bending responses to that of the human model. The study also found that a mass of 6 kg attached to the impactor top could improve the femur kinematics when impacted to SUVs.

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Two motor hybrid system was designed with using original two output coaxial motor and the transmission unit was made experimentaly. Motor- and system-characteristics were optimized to each other and these coaxial components were carefully combined and arranged in the unit so that the unit can handle 2.5L-gasoline engine while the length is 350mm.

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The permanently engaged gear mechanism has been developed for new idle stop system. It realizes excellent low NV and quick response during engine stop and restart phase, and also responds immediately to driver's engine restarting request before the engine is completely stopped. The system concept was realized through comparison of various engine starting methods, which finally resulted in the selection of a permanently engaged gear mechanism as best system for stop&start functionalities. Analysis of issues such as mechanical component stress and usage conditions was done usig simulation, evaluation with real vehicles, component unit test and field tests. Thereafter this mechanism was designed appropriately and full reliability of the engine starting process was realized.

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A new fuel cell vehicle which displays an improvement in driving performance and fuel consumption performance has been developed. It is fitted with a fuel cell power train with V Flow FC stack at its core. The new configuration has enabled the achievement of weight savings, increased compactness, with an increase of 200% in weight power density and 220% in volume power density against the previous model. Increased power train efficiency and energy management have increased driving energy efficiency by 60%, resulting in a 20% increase in fuel consumption performance and 30% increase in driving range.

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A new DC brushless motor has been developed as the electric drive motor for the new fuel cell vehicle. A coaxial configuration was employed for the drive motor and gear box, enabling miniaturization of the drive unit. Owing to optimization of a magnetic circuit, the electric drive motor achieves a maximum power of 100kW, maximum torque of 256 Nm.
The application of the motor has enabled expanding interior space, the dynamci performance equal to 2.4L gasoline vehicle, and increasing curising distance.

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In this paper, a noncontact magnetostriction type torque sensor using iterative periodic time difference detection method and its application to a rotational axis torque detection are described. In order to apply the proposed method to the rotational axis, i) reduction of the sensor hysteresis due to the magnetic characteristic of materials, ii) reduction of the sensor ripple due to the characteristic difference of material surface, and iii) reduction of the sensor drift to occur by a temperature change are examined and carried out. As a result, it is shown that the sensor ripple and the sensor drift can be suppressed about 1.0 Nm (p-p) and less than 0.5 Nm, respectively.

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In order to save weight and increase productivity, the FC subframe developed for vehicle mounting of the fuel cell system employed in the FCX Clarity fuel cell vehicle is constructed from both extruded and cut parts produced from 6000 series aluminum alloy. Friction stir welding (FSW) was used to weld the main structural parts of the subframe. FSW was applied to 12 types of lap joints and one type of butt joint. Five tools were developed for the lap joints and one tool for the butt joints.

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The specific corrosion mechanism and its prevention method for decorative Cr plating in the presence of highly concnetrated calcium chloride is studied. It is investigated by lavoratory test and market monitoring that Cr plating, whose Cr ratio is 98%, is easily attacked in such corrosive environment. It loses the passivation film by chloride ion and the electropotnetial of Cr shifts to base. Therefore the relationship of galvanic cell between Cr and underlying Ni is switched, and after that the anodic dissolution of Cr is occurred. In addition to the above study, the prevention method aganist such specific corrosion is suggested. Cr-C plating, whose Cr ratio is 60-80%, is investigated by AES and XRD. It contains metalloid element(s) into the film which contribute(s) to organize amorphous. It consists of Cr-C clusters which are coated by oxide phases. Thus, the potnetial shift which causes Cr dissolution is prevented consequently.

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In this paper, a new riveting method of which the joining of the sheets was possible without drilling of the sheets as well as the easy disjoining of the joint also was possible was proposed. And the riveting method was applied to the joining of cold-reduced carbon steel sheets. The joining was carried out by the following process. A rivet set on the sheets was stuck into the sheets using a high-speed weight. Then the axis of the struck rivet penetrated the sheets. Finally, the rivet axis which went through the sheets was jointed with a rivet holder set under the sheets and the sheets were tightened by the head of the rivet and the rivet holder. For the joint produced by the proposed riveting method, the distortion and plastic deformation of the joined plates, static and cyclic joint strength were examined by comparison with those of the joint produced by ta conventtional riveting method such as caulking. From the resutls, it was found that the joint produced by the impulsive riveting method was superior to the joint produced by caulking, in addition, the joint produced by the impulsive riveting method was able to be disjoined easily.

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This paper proposes a method of course map generation and the employment of the map for autonomous driving on the precincts roads. This proposal aims at improvement in availability in consideration of the robustness over the position measurement at the time of course map generation and its employment. Generation of a course map is carried out using the information on the moving trajectory by letting instruction driving of the experiment vehicles along a road by manual operation. The position measurement value with RTK-GPS on vehicles is used as the base to the position information on a course. A map is generated by making the moving trajectory into course information using a set of the sequence of a point. At the time of course mapping, in cases where the measurement accuracy of RTK-GPS is poor, it adjusts using a vision system or LRF. This paper also describes an experiment of proposed system using RTK-GPS, vision system, LRF and an experimental vehicle. An experiment of course mapping using an experimental vehicle with RTK-GPS and vision system is described to verify the proposal.

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In the current GPS-based automatic driving control, a vehicle has been controlled to follow a target trajectory stored as position data and it is necessary to rearrange the trajectory data for dealing with temporary changes of the course, for evading obstacles and for realizing bidirectional traveling. This study developed control algorithm using the information of the region that a vehicle can enter and the region that the vehicle cannot enter, and validated the algorithm by experiments. The fruit of this study makes it easy to realize temporary change of course, obstacle evasion and bidirectional traveling at the GPS-based automatic driving.

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A method to identify the vibration transfer function from combustion pressure to engine structural vibration was developed without using complicated apparatus. In the method, which uses Maxwell's reciprocity theorem, a shaker excites structural vibration and the pressure in the combustion chamber is measured. A feasibility study on a simple structure produced transfer functions in the forward and reverse directions that coincided almost perfectly in the relevant frequency range. Transfer functions on a gasoline engine showed reasonable peaks of structural resonances. The method is convenient for identifying peak frequencies of the transfer functions between combustion pressure and engine structural vibration responses.

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Energy absorption performance of CFRP is determined by progressive fractures, and it is important to predict the occurrence of the initial fracture inside the ply and its relation with the final fracture mode. Therefore numerical calculations were performed considering a progressive fracture of ply. In the progressive fracture model, fractures are classified into two kinds - fiber frectures and matrix fractures. When the fracture threshold is reached inside plies, the stiffness value is decreased. The progressive fracture model was applied to dynamic behaviro for CAE and the occurrence of fractures and the load characterisitcs were examined, taking a beam subjected to bending load as an example. This study showed that calculation using the progressive fracture model matched the experimental results in the early stages with an example dynamic bending load.

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It is important to identify the collision point when reconstructing a traffic accident. Investigators including police officers sometimes have to determine the collision point based only on the stop positions of broken parts. However, few studies have been conducted to clarify the mechanism of such phenomenon. We have started to conduct car-to-car collision tests to understand the mechanism. This paper, focusing one-dimensional car-to-car collision, shows the clarified mechanism and the relation between collision points and stop points of broken parts.

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For steer by wire system, it is possible to design a reaction torque controller to assist driver's steering operation. This paper investigates the characteristics of the reaction torque control based on the feedback from the steering wheel angle, the steering force and the vehicle behavior, respectively. Two phases are considered for an actual vehicle test: 1) the driver-made phase to enter into a turn, and 2) the vehicle-made phase to exit the turn. Four basic guidelines are defined to evaluate the reaction control policies. No single policy can satisfy all the guidelines and the necessity of a mixed policy is clarified.

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This study examines to design a lane keeping controller for motorcycles and to evaluate it by using the multibody-dynamics model. By examining the simulation with the rider-in-the-loop system consisting of the motorcycle, the lane keeping controller, and the rider control model, good lane keeping performance is achieved without interference between the control input and the rider's input. The steer-by-wire system also improves the lane keeping performance in comparison with the conventional motorcycles.

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This paper explores the relationship between the oscillatory variations of the frictional forces developed in braked tires and the several kinds of tire characteristics obtained from experiments. Among others, the transfer function of tires when excited in fore-aft direction is then highlighted, and the fundamental role of the tread rubber is investigated in terms of the transient properties by the aid of the so-called brush model

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This paper introduces application study of 'DREAMS'(driver's expectation and motion sensitivity) for improving 'roll feeling'.From subjective comment of test drivers who specialize in the evaluation, it is indicated that the relative movement between instrument panel and ground plays a major part in the perception of roll feeling. Then the optimal shape of instrument panel which increases driver's visual perception threshold of the vehicle roll motion by minimizing relative movement between instrument panel and ground is proposed. Further, improvement in 'roll feeling' of the vehicle with optimal shape instrument panel is examined by subjective evaluation.

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We clarified properties of a visual pattern discriminable by peripheral vision and free from any effect on eye movement and accommodation by psychophysical experiments so as to realize an ambient information display neither entailing nor interfering with foveal vision. We obtained specifications of a visual pattern suitable for the ambient information display and discussed what kind of information may be transmitted using the proposed visual pattern which we named will-o'-the-wisp.

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In the motion control by the suspension system, it is important to evaluate driver's pose keeping and steering control to stabilize vehicle attitude. In this paper, analysis of driving maneuvers in slalom running has been executed by using newly designed rolling simulator and the car.
As the result, it was confirmed that steering control including driver's head motion was analyzed and visual information and the size of roll angle took part in steering control. We report the result that was analyzed about a steerage function of a driver in a human-car corollary.

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This paper presents a measurement technique for visualizing the two dimensional distribution of the in-cylinder sauter mean diameter (SMD) and analyzing the effect of the SMD distribution to mixture formation on direct injection (DI) engine.First, a technique for visualizing the SMD distribution based on the SMD dependence of fluorescence and Mie Scattering ratio is described.
As the next step, this method was applied to optical engine in two engine condition of different engine speed. The correlation between the SMD distribution and mixture formation was shown experimentally by changing in- cylinder gas flow.

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The effects of mixture dilution with CO₂ on outwardly propagating laminar and turbulent flames were studied for stoichiometric iso-octane / air mixtures at the initial pressures from 0.10 to 0.50MPa. The CO₂ dilution rate, defined as the molar fraction of CO₂ in the air and CO₂, was varied up to 0.10. The unstretched laminar burning velocity decreased with increasing the dilution rate. The Markstein number decreased for increasing CO₂ dilution rate. The ratios of turbulent burning velocity to unstretched laminar one increased with increasing CO₂ dilution rate.

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This study was aimed at clarifying the relationship between cylinder bore deformation and lubricating oil consumption(LOC), using a conventional in-line four-cylinder gasoline engine. The rotary piston method developed by the author et al. was used to measure the cylinder bore deformaition of the engine. In addition, the sulfur tracer method was applied to measure LOC of each cylinder. We then made a calculation of piston ring oil film thickness, using a model to predict a ring's conformability considered cylinder bore deformetion. The results were used to calculate the rate of oil flow into a combustion chember, and the rate of oil evaporation from a cylinder wall. As a result of the measurements and the calculations, we consider it necessary to improve cylinder deformation at the cylinder's upper part, and ring's conformatiblity performance to a cylinder for the purpose of controlling increase in LOC.

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A newly developed small-sized IES(inductive energy storage) circuit with a semiconductor switch at turn-off action was successfully applied to an ignition system. This IES circuit can generate repetitive nanosecond pulse discharges. An ignition system using repetitive nanosecond pulse discharges was investigated as an alternative to conventional spark ignition systems in the previous paper(1). Experiments were conducted using spherically expanding flame condiguration for CH₄ and C₃H₈-air mixtures under various conditions. The ignition system using repetitive nanosecond pulse discharges was found to improve the inflammability of lean combustible mixtures, such as extended flammability limits, shorted ignition delay time, with increasing the number of pulses. In this paper, the authors seek for the mechanisms for improving the inflammability in more detail to optimize the ignition system for a real engine use. Moreover, an application of this ignition system to a SI engine was conducted. As a result, the lean limit was extended from 20 to 23 in A/F at IMEP 440kPa by replacing the ignition system from a conventional one, and indicated thermal efficiency was improved by 11%.

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EGR combustion system is one of the pormising ways of NOx reduction in diesel engine. In EGR system, hot exhaust gas is recirculated from the exhaust side of engine to the intake side. To ensure the high ratio of EGR and high volumetric efficiency of it, hot exhaust gas should be cooled down with EGR cooler. Then EGR cooler with high cooling performance is required for high efficiency and ultra low emission diesel engine. To improve the performance of EGR cooler, exhaust gas deposits in it should be eliminated, because heat transfer performance is deteriorated with the deposits. In this study, new evaluation method of deposits in EGR cooler was proposed as teh first step of EGR cooler improvement. Deposits in EGR cooler were oxidized in a special designed furnace and soot and hydrocarbon in the deposits were estimated with gas analysis of O₂ and CO₂ in the furnace. Total deposits mass obtained from gas analysis showed good agreement with the deposits mass obtained by a gravimetric method. The gas analysis showed that 80% of deposits mass was carbon. Further, heat transfer performance of the EGR cooler was evaluated and its relationship with deposits was discussed.

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Interaction of fuel spray and surrounding air plays an important role on mixture formation, ignition and combustion processes in diesel combustion. Effects of ambient gas density and temperature on development, ignition and combustion processes of diesel spray were investigaed by using free piston type rapid compression machine and high-speed video camera. The obtained images at ignition and combustion process were analyzed using their color information. Two types of flame including dark and bright one are found in all cases except low temperature cases. Dark flame fragment is always found ahead of appearance of bright flame fragment. Dark flame is found at relatively well-mixed region. Bright flame is found only at fuel rich retion, such as nearby spray axis and spray stagnating region in high-density condition.

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Improving fuel cell (FC) stack durability is one of the largest issues to be addressed for commercializing fuel cell vehicles (FCVs). With the aim of improving FC stack durability, a method of estimating stack durability has been developed by using FCV operating data obtained on public roads and proving grounds and the results of durability tests conducted with test benches. An overview of the estimation method is given and the validation of its accuracy is also described.

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The high power density, lower cost and improved durability are the most important issues for fuel cell stack . New fuel cell stack achieves double the power denstiy of the previous stack as a result of improving the proton conductivity of the electrolyte membrane and applying metallic bipolar plates. Both lower cost and higher durability have also been achieved by halving the amount of catalyst used and controling catalyst degradation reaction. This paper gives an overview of the new stack and its technical features.

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From the consideration of practical use of the direct-injection spark-ignition (DISI) hydrogen engine, the output performance and combustion processes are systematically investigated for various injection and ignition timings at different injection pressures. It is shown that almost the same thermal efficiency can be achieved even at a lower injection-pressure condition as long as the injection and spark timings are adequately controlled with engine loads. Based on the obtained results, the strategy for selecting the parameter of operating conditions are proposed and then the feasibility of DISI hydrogen engine are demonstrated.

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The mechanism of HC formation in PCI may be different from that in conventional direct-injection diesel becuase injection timing of a PCI engine is considerably earlier than that of a conventional diesel engine.
In this study, the characteristics of HC and CO emissions in a PCI engine were investigated by changing combustion chamber geometry(cavity diameter), topland volume, injection timing and piston surface temperature in experiments. At the same time, the simulations of spray and air-fuel mixture formation were conducted by using GTT code. The relationship between HC and CO formations and mixture distribution was tried to clarify. As a result, HC and CO emissions in PCI engine are depended strongly on the fuel distribution in the cylinder and would increase if fuel extruded out of cavity and entered the squish area.

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This paper is clarifying the exhaust emissions characteristics of in-use DI diesel vehicle in actual running condition. Various measurement instruments were installed in test vehicle (passed 1988 Japanese exhaust emission regulation), and a micro dilution tunnel (MDLT) system was installed in the vehicle. Then, the actual running experiments were carried out for the test route including expressway and local street around Doshisha University. PM was separated into soluble organic fraction (SOF) and insoluble organic fraction (ISOF) with applying a soxhlet extraction technique, and the relation between the running conditions and the PM component was investigated.

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Purpose of this study is to evaluate effect of mixing the each Fatty Acid Methyl Ester(FAME) on spray combustion characteristics. The FAME is pure substance composing BioDiesel Fuel, having 8-18 carbon(C8-C18) and 1-3 double bounds in 18 carbons(C18:1-C18:3). The C10, C14, C18 and C18:2 are selected in C8-C18 and C18:1-C18:3. In these FAMEs, the C10 and C18 are equally mixed by volume ratio. As well, the C18 and C18:2 are mixed. In this study, shadowgraph photography is performed to clarify macroscopic spray combustion characteristics of test fuels using constant combustion vessel. The results indicate that spray combustion characteristics of mixing FAMEs have each FAME characteristic.

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Carbon canister is an evaporative emission control device to prevent the release of evaporative fuel gas from gasoline tank by the gas adsorption with activated carbon. However, there is still concern that evaporative fuel gas is released into the atmosphere, even when the vehicle is parked, because of the diffusion caused by the concntratin differnces of adsorbed gas.
In this study, we conducted basic experiments and calculations to reveal the behavior of gas diffusion in carbon packed bed.
As a result, we understand the mass transfer phenomenon in carbon packed bed. Furthermore, the gas diffusion can be estimated by numerical calculation.

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A simple real-time measurement system for the components of volatile organic compounds(VOCs) and polycyclic aromatic hydrocarbons(PAHs) in automobile exhaust gas using a laser ionization method was developed. In this method, many kinds of VOCs and PAHs were observed simultaneously, and real-time changes of their concentration were obtained at 1 second intervals. As a test measurement, exhaust gas from a motorcycle was monitored in real-time, and real-time concentration changes of many kinds of hydrocarbons like toluene(92), xylene(106), trimethylbenzene (120), naphthalene(128), etc., were observed. Using this method, real-time assessment exhaust gas can be developed.

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Measurement of multi-components of volatile organic compounds(VOCs) and polycyclic aromatic hydrocarbons (PAHs) in diesel exhaust gas in mode driving have been performed with a laser ionization method. VOCs and PAHs, whose mass were between approximately 90 and 300, were simultaneously detected during mode test. Various kinds signals of VOCs and PAHs such as naphthalene(128) and triple-ring PAHs(178) etc were able to be obtained every 1 second. It was found that their emission trends were different from each other. Among them, the naphthalene was calibrated using the standard sample.

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Recent concern about environmental issue have been focused not only carbon dioxide but also rare metals including precious metals which have been usually used as exhaust gas purification catalyst for automobile. For the decrease of the use of precious metals, a new exhaust catalyst which is durable and containing lower amount of precious metals is desired. So, the authors have tried to prepare Mn-substituted lanthanum hexa-aluminate(LaMnAl₁₁O₁₉) crystallites, and applied the crystallites as support material for Pd catalyst. In this report, preparation procedures of he crystallites and Pd loaded catalyst were described and the catalytic performance and durability were also mentioned.

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Evaporation and combustion experiments of a single suspended droplet of palm oil methyl ester (PME) and its components of fatty acid methyl esters (FAME) were performed to obtain fundamental data related to spray combustion. PME droplet evaporation at relatively-low temperatures slows down drastically on the latest stage of evaporation. It is supposed to be due to alteration of the unsaturated FAMEs in PME during evaporation.

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In order to improve the pour point of palm oil biodeisel, palm oil isobutyl ester (PiBE) is made with isobutanol by transesterification. As a result, the pour point of PiBE is 0°C and it is lower than that of palm oil methyl ester (PME), 12.5°C. The combustion characteristics and exhaust emissions of PiBE are investigated using a DI diesel engine, and are compared with that of PME, palm oil 1-butyl ester(PBE), repeseed oil methyl ester(RME) and JIS No.2 gas oil. The thermal efficiency of PiBE is almost the same as that of the other test fuels. Although the HC, CO and Smoke emissions of PiBE are slightly higher than that of PME, these are lower than that of the gas oil. It is concluded that PiBE is a good alternative diesel fuel.

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Efforts towards using P3 component of EFRP(Eye-Fixation Related Potential) as an evaluator for information recognition process are presented here. Seven experimental subjects were required to execute a simulated driving task and five visual tasks which differ in the complexity of decision process. EFRP was calculated from EEGs which artifacts are eliminated by the ICA method and P3 components were able to be identified in five subjects. The P3 latency showed a correlation with response time and subjective strain caused by visual tasks. It suggests a possibility for using P3 latency of EFRP in the assessment of driver's cognitive load.

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Lane change maneuver is one of the difficult driving maneuvers for inexperienced drivers. In this research, we aim to study and evaluate human errors and risk factors in lane change behavior, and use the obtained understandings for driver education. Driving data was collected by using a continuous sensing drive recorder mounted on a vehicle, and a database which stores the extracted data segments during lane change was constructed. The analysis was conducted from lane change patterns classified by lane change situation and the characteristics of the driver. Here, we observed, for example, safety confirmation of the side and rear on the vehicle, turn indicator timing, steering and pedal operations, etc. From this analysis, we also investigate the indices that can be used to evaluate individual lane change behavior.

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To reduce rear-end crash, it is important to judge necessity of deceleration assistance as earlier as possible and initiate the assistance naturally. On the other hand, we have derived a methematical model of driver's perceptual risk of proximity in car following situation and proposed driver deceleration model and deceleratin control mehtod. In this research, we will discuss a method to build deceleration control method to realize comfortable driver assistance by considering how assist initiates and where to be converged and how to connect these two based on the driver's perceptual risk.

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