Shoulder support of seat is considered to affect driver's ease-of-steer feeling. During virtual slalom maneuver on a six-axis shaker, driver's motions and the forces and torques applying to steering wheel and seat back were measured in four different shapes of seat back. Then, the line of action regarding these forces and the glenohumeral joint torque about the axis parallel to steering rotation axis were estimated. The results indicate that the seat back force keeps applying to driver's moving scapula on outer side of a turn, glenohumeral joint torques contributing to steering wheel rotation are reduced, thereby possibly enhancing ease-of-steer feeling.

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The experiment and the numerical simulation are respectively carried out to understand the characteristics of unsteady flow in an exhaust manifold to improve the performance of automobile engines,. The velocities inside each pipe below the exhaust port and the converging part of the exhaust manifold are measured by LDA and PIV. The large velocity and oscillating flow are observed at the manifold part. The organized vortex motion, mixing, and collision are generated at the converging part. The results both PIV and CFD become similar flow pattern in the converging part.

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In water pump for automobile engine, and the measured pressure of flow reduction point on N-Q characteristics, and devised a method to cavitation occurrence prediction from the cooling system suction pressure, from the calculation of the minimum pressure in the pump according to this prediction method and CAE analysis, cavitation occurrence was suppressed by improve design of the impeller, the effectiveness was confirmed.

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The purpose of this research is to develop visualization techniques for the rotating fan and achieve high performance with the two-layered-HVAC (Heating, Ventilation, and Air-conditioning). Three techniques helped to obtain flow visualization images more accurately. First, it was to capture stationary images of a rotating fan by applying image-processing techniques. Secondly, it was to always irradiate the same flow between the blades with laser. Thirdly, passing through micron-sized mist tracers of which diameters determine the traceability of sedimentation velocity, centrifugal force, etc., effectively visualizes the flow. As a result, better accuracy and reliability of flow visualization images can be achieved.

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Experimental and theoretical studies on Chemical Heat Pump was performed for improving the fuel efficiency of vehicles by recycling the engine waste heat to the engine warming up and the room air conditioning. As a result, an exhaust gas energy was chemically stored in CaO/Ca(OH)₂ reactant of Chemical Heat Pump unit at 1.86 MJ/kg-CaO, and recycled to hot/cold heat for engine-starting/running. Possibility of improving the fuel efficiency of vehicles about 23% in JC08 mode with an air conditioner and reducing the environmental impacts about 19% was shown by the experiments and calculations.

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We developed a magnetically formed decorative painting for plastic coverings of motorcycles. By using reflective flakes with strong magnetic permeability and adding high molecular weight resin considering behavioral characteristics of flakes to magnetic lines of force, we developed a control method to align the flakes in a desirable manner. As a result, it was achieved to create an enhanced three dimensional appearance compared to the former method. The developed painting contributed to make motorcycles more attractive in the market.

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Our company launched its FCV in December of 2014. The future expansion of the FCV market will require a reduction in the amount of platinum used in each FCV. Toward this end, platinum degradation is one of the most important issues to be addressed. This research group decided to conduct in-situ liquid TEM analysis to clarify the mechanism of platinum degradation. So far, we have succeeded in establishing a methodology, i.e., cyclic voltammetry measurement, to observe the dissolution and aggregation of neighboring platinum particles under electrochemical control. As a result, it is believed that new materials can be developed that will limit degradation and assist in the optimal design of FC electrode catalysts, and new methods of catalyst usage can be suggested that will avoid degradation in FC systems.

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The stress triaxiality dependent fracture criterion for strength estimation using simple uniaxial tensile test specimens with a center hole and edge notches, has been successfully identified in the previous reports. In this study, to measure the fracture strain of three classes of advanced high strength steels under the shear stress state, two new shear test specimens named by bear-face specimen and slit specimen, respectively, and their testing methods were developed. Totally, three types of shear testing including a conventional butterfly shear test were performed. Three finite-element models corresponding three types of shearing specimens were developed and fracture strain was identified. It was repeatedly observed in experiments that the cracks initiated at the edge of all shear specimens where the stress triaxiality is near the plane strain rather than pure shear stress state according to the CAE results computed by FEM.

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A finite element analysis (FEA) model for predicting the weld fracture is developed using local equivalent plastic strain coupled with the stress triaxiality σm/σ (σm: hydrostatic stress, σ: equivalent stress) as a fracture criterion. In this report, this FEA model is applied to tension tests of laser welded joints. FEA results show good agreement with experimental results, such as joint strengths or fracture modes. This method enables clarification of the laser weld fracture phenomenon and the accurate fracture prediction under the varied load modes.

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In automotive turbocharger, blackening of bearing can be observed in case of the copper alloy. The phenomenon is copper corrosion caused by ZnDTP in lubricating oil for automobile engine. However, it has been hardly reported for the correlation of the metal and the blackening. Therefore, the propagation of blackening was evaluated using various bearing metals. In addition, the detailed phenomenon and the effect of metal on the blackening were considered.

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Remote laser welding between coppers is used in our HV inverter. Moreover, many studies of in-process monitoring system using such as reflected light, plasma light, and heat radiation have been reported. However, it is difficult to apply their monitoring systems in product line due to large high frequency noise and not satisfactorily measuring weld area. In this paper, we showed that plasma light not only can detect lack of penetration, but can calculate weld area in quantitative terms using multiple regression equation. These results provide improvement of laser process monitoring accuracy as well as new quality assurance system.

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Measurement methods of radiated disturbance below 30MHz and characteristics of semi-anechoic chambers to be used for the measurement are currently being discussed at CISPR/SC-D. Hence, theoretical calculation and comparative reviews between values measured in semi-anechoic chamber and those measured on various types of road surface are implemented. The aim of the experiments is to incorporate the equivalent earth ground plane in semi anechoic chamber which approximates to Japanese car manufactures’ unique ground reflective characteristics into the CISPR standard.

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In autonomous driving it is necessary to generate a path of lane change which considers dynamic environments of surrounding vehicles and the characteristics of the driver’s operation. In this paper, a new path generation method of lane change is proposed by combining two dimensional relative coordinates of vehicle planar position with time coordinate of vehicle motions. The proposed method can cope with both safety and the characteristics of the driver’s operation by perfom1ing the optimization with an evaluation function including own acceleration, jerk and distances to surrounding vehicles. Some simulations show the effectiveness of the proposed method.

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