There is a high demand for recycling of copper used in vehicle body parts. A modeling technique was developed for simulating rupture of wire harness during a dismantling process of a vehicle body. The diameter and stiffness of the wire harness was represented in the model. The model well predicted the actual rupture location when the wire harness was entrapped by other parts. The model also indicated that the rupture risk could be lowered when the direction and order of dismantling process were changed.

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It was known that the vehicle fuel consumption under the mobile air conditioner (A/C) operation is increased in accordance with increase of the specific enthalpy in the test cell. In this study, we evaluated the estimation method for the fuel consumption under the A/C operating condition in the representative summer condition based on the relationship between the specific enthalpy in the test cell and fuel consumption. It was found that the difference between the estimated fuel consumption and the measured fuel consumption in the environmental condition of 71 kJ/kg(DA) was approximately 1.6%.

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New index “NOx emission (g) per CO₂ 1 kg” is calculated by data of NOx and CO₂ emission measured with using the sensor-based emission measurement system (SEMS) consisting of a NOx sensor, a digital tachograph and a gas flow meter. And then we proposed a method to monitor NOx purification performance at road driving with using the above-mentioned index and exhaust-gas temperature. Moreover, we applied this method to a deterioration diagnosis for a urea selective catalytic reduction (SCR) system. As a result of consideration based on deterioration case, it was indicated that this method is effective for the diagnosis.

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In order to clear the characteristics of nano-PM (nanometer order particle matter) exhausted from diesel engine, PM behavior in exhaust line of small size diesel engine was investigated. In this study, PM number and mass concentration distributions were measured along the exhaust line using SMPS (Scanning Mobility Particle Sizer) and LPI (Low Pressure Impactor). Volatile and non-volatile compositions in PM were separated by drying under 120˚C and 240˚C. As the result, it was shown that number and mass concentrations of larger size PM at downstream part in exhaust line under high speed 0% load condition was higher than those of the upstream part. Smaller size PM at downstream part in exhaust line under 40% load condition was lower than those of the upstream, although smaller size PM under 70% load condition was higher than those of the upstream. Mass concentration of dry240˚C PM under 40% load condition decreased along exhaust line, although mass concentration of dry240˚C under 70% load condition increased. Under 70% load condition, additional soot seems to be formed in the exhaust pipe.

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Recently, high speed tensile test is being recognized as a standard testing method to confirm the strength under dynamic loads for engineering plastics. In our previous study, elastic strain rate concentrations are discussed by FEM. In this study, elastic-plastic FEM analysis is performed to confirm the real strain rate appearing at the notch root. Then, the master curve for the final fracture elongation for polycarbonate is constructed. It is found that the fracture behavior can be predicted for the wide range of impact speed under various temperatures from the master curve based on elastic-plastic analysis.

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To adopt aluminum alloy in structure, it is important to develop most suitable joining technology. This paper describes effect of factors to fatigue strength in aluminum spot laser welding with tensile shear joint. In the range of this study, distance between sheets and thickness occupies most of the contribution, so those are important factors to fatigue strength.

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The finite element model considering that the material parameters for cohesive zone elements were appropriately determined from the out-of-plane experimental measurements of randomly oriented thermoplastic CFRP composites, which are superior in lightweight and productive efficiency, was applied to a numerical simulation analysis for axial collapse behavior of their crash boxes. The simulated results demonstrated well the progressive delamination failure mode and the energy absorption performance of the crash boxes compared to the weight-drop experimental results. This enabled to investigate the effect of the composite properties on the energy absorption performance of crash boxes.

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The experiments were conducted on pipe diameter reduction by spinning forming process with ferritic stainless steels. The target shapes of this study are the automotive exhaust parts, such as catalytic converters or sub-mufflers. Effects of the several forming condition factors on the geometrical property or defects of the parts are clarified. Computer aided engineering (CAE) simulation model was also developed for spinning forming. The calculated results were in good agreement with actual specimens not only in thickness distribution but also in shape of buckling defect. The results suggest that CAE simulation could be a helpful tool to obtain optimum forming conditions.

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The needs for precise combustion control are continuously growing now to realize a higher level compatibility between attractive performance (e.g.higher heat efficiency, higher torque, etc.) and environmental protection requirement. To control combustion, i.e. to design heat release rate, we consider that following 3 factors are important, i) design freedom, ii) compensation, and iii) robustness. We developed intelligent Accuracy Refinement Technology (i-ART) to accomplish these factors for injection rate control. It is the world’s first system that realizes closed-loop fuel injection control by direct detection of the injection pressure using a pressure sensor built-in to the injector. In this paper, the importance of injection rate feedback technology to achieve precise combustion control is discussed.

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For a fuel economy of a gasoline engine, a precise control is required to optimize many operating parameter in transient state. The model predictive controller(MPC) is paid attention as an optimal controller design method. In case of the MPC was designed by means of a linear model about objective system, the control performances were deteriorated on account of parameter vary. However, an optimal control can be satisfied whenever the model parameter of the controller well coincided with those of the control target. This paper investigated about on-line adaptation of MPC using genetic algorithm for Air-Fuel-Ratio control in transient state.

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Automated vehicle researches move on to the public road experiments. This study focuses on a traffic signal detection based on mono-camera, predefined map database and accurate vehicle pose which is estimated by a localization module. An image ROI (Region-Of-Interest) can be calculated by the map data and the vehicle pose. This paper handles a situation with multiple signals appeared in an ROI. We propose a probabilistic method for an image location of the target traffic signal in order to realize simultaneous traffic signal detection for urban driving. Experiments show the performance of the proposed method for real driving data.

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“Sailing Stop” which disengages clutches and stops fuel supplies during running is studied for improving fuel economy. We are developing the technology that combines "Sailing Stop" and ACC (Adaptive cruise control) to stop engine at appropriate timing and operate engine at high efficiency region automatically for improving fuel economy. In this system, it is necessary to operate engine at high efficiency region quickly for demanded driving force. In this paper, we propose a new engine and transmission control method based on predicted driving force. The experimental results show that the efficiency at acceleration was improved and fuel consumption was reduced by 9.1～31.3% at 40～60km/h.

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A method was developed to detect the direction of the passing beam or generally called low-beam. This method was integrated into a headlight tester and tested in the field. Then the main algorism was optimized by trials. The obtained results suggest this method can improve the accuracy.

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It has been reported that a fraction of the ash generated by a diesel engine can pass through the diesel particulate filter (DPF), causing malfunctioning of the PM sensor. In this study, to elucidate the mechanism of the ash slip, the components of ash passing through DPF due to condensed water in exhaust were measured using a HPLC and XRD. The ash sample used in this experiment was generated by an accelerated ash formation system constructed by our own, which consisted of a diffusion flame burner. It was confirmed that the components of the generated ash using the developed system were similar to those of real-world ash accumulated in DPF. The experiments for the ash slip through DPF using the diesel engine exhaust and the generated ash were performed. The components of the slipped ash through DPF contained mainly Ca²⁺ and SO₄ ^2-, which indicate that the CaSO₄ included in the ash dissolves in condensed water in the exhaust and passes through DPF.

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