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To avoid a trial and error adjustment for designing EMI filters, clarifying load impedance of operating condition, i.e., dynamic impedance of equipment is very useful. Therefore the need to a non-contact measurement method of the impedance connected to a wire harness is increasing rapidly. A measurement method using a network analyzer with two current probes was previously proposed. However, it was confirmed only up to 30 MHz. Many radio equipment operate above 30 MHz such as FM receivers and GPS receivers installed in vehicles. So increasing the measurement frequency is necessary in the auto industry. At first, we tried to expand the applicable frequency to 100 MHz, i.e., FM band. In this study, we applied the transmission line theory using the non-contact measurement method. Furthermore, in order to use the theory, the characteristic impedance and phase constant of the wire harness are required. So we made an additional measurement to estimate them.

Compact, high efficiency and high reliability are required for an xEV motor generator. IPM rotors with neodymium magnets are widely applied for xEV motors to achieve these requirements. However, neodymium magnet material has a big impact on motor cost and there is supply chain risk due to increased usage of these rare earth materials for future automotive xEV’s. On the other hand, a wound-field rotor does not need magnets and can achieve equivalent performance to an IPM rotor. However, brushes are required in order to supply current to the winding coil of the rotor. This may cause insulation issues on xEV motors which utilize high voltage and high currents. Therefore, it is suggested to develop a system which supplies electric energy to the rotor field winding coil from the stator without brushes by applying a transformer between stator coil and rotor field winding. Specifically, add auxiliary magnetic poles between each field winding pole and wind sub-coils to these poles.

Modern vehicles utilize various functionalities that require security solutions such as secure in-vehicle communication and ECU authentication. Cryptographic keys are the basis for such security solutions. We propose two approaches for secure and efficient invehicle key management. In both approaches, an ECU acting as a Key Master in the vehicle is required. The first approach is based on SHE. The Key Master generates and distributes new keys to all ECU based on the SHE key update protocol. The second approach performs key establishment based on key derivation. The Key Master sends a trigger in form of a counter and all ECUs derive new keys based on the received counter value and pre-shared keys. It is thus possible to handle in-vehicle key management without the need for an OEM backend to manage all keys. This reduces cost and complexity of the solution.

We developed a technique to measure oil film pressure distribution in engine main bearings using thin-film pressure sensors. The sensor is 7μm in thickness, and is processed on the surface of an aluminum alloy bearing. In order to increase the durability of the sensor, a layer of MoS2 and polyamide-imide was coated on thin-film sensors. This technique was applied to a 1.4L common-rail diesel engine operated at a maximum speed of 4,500r/min with a 100Nm full load, and the oil film pressure was monitored while the engine was operating. The measured pressure was compared with calculations based on hydrodynamic lubrication (HL) theory.

A new clean diesel combustion concept has been proposed and its excellent performance with respect to gas emissions and fuel economy were demonstrated using a single cylinder diesel engine. It features the following three items: (1) low-penetrating and highly dispersed spray using a specially designed injector with very small and numerous orifices, (2) a lower compression ratio, and (3) drastically restricted in-cylinder flow by means of very low swirl ports and a lip-less shallow dish type piston cavity. Item (1) creates a more homogeneous air-fuel mixture with early fuel injection timings, while preventing wall wetting, i.e., impingement of the spray onto the wall. In other words, this spray is suitable for premixed charge compression ignition (PCCI) operation, and can decrease both nitrogen oxides (NOx) and soot considerably when the utilization range of PCCI is maximized.

In diesel engines with a straight intake port and a lipless cavity to restrict in-cylinder flow, an injector with numerous small-diameter orifices with a narrow angle can be used to create a highly homogeneous air-fuel mixture that, during PCCI combustion, dramatically reduces the NOX and soot without the addition of expensive new devices. To further improve this new combustion concept, this research focused on cooling losses, which are generally thought to account for 16 to 35% of the total energy of the fuel, and approaches to reducing fuel consumption were explored. First, to clarify the proportions of convective heat transfer and radiation in the cooling losses, a Rapid Compression Machine (RCM) was used to measure the local heat flux and radiation to the combustion chamber wall. The results showed that though larger amounts of injected fuel increased the proportion of heat losses from radiation, the primary factor in cooling losses is convective heat transfer.

Instrument clusters that display all information on a TFT-LCD screen, also known as reconfigurable instrument clusters, have become the new trend in automotive interiors. DENSO mass-produced the world's first reconfigurable instrument cluster in 2008. To satisfy customer requirements, large quantities of resources were required. Coupled with an iterative process due to requirement changes, development costs became very high. Reducing development costs was vital in order to expand the reconfigurable instrument cluster products line. One solution was to use existing human machine interface (HMI) tools. However, most HMI tools are geared toward software developers and not graphic artists. Furthermore, each tool has its own unique method for image and scene creation, creating an ineffective and sometimes difficult environment for artists familiar with industry-leading computer graphics (CG) software to learn and use the tools.

The causes of deaths in traffic accidents are predominantly human factors such as careless or "heedlessness" driving; recently, accidents that are believed to be due to deteriorated physical conditions, such as heart attacks, have been reported. Non-contact electrocardiography (ECG) monitor for continuous ECG detection while driving is needed to reduce a number of fatal accident by human error like this. Recently there are a lot of papers to detect cardiac electricity using capacitance coupling between human body and electrode. This sensor system must be adopted appropriate high input impedance circuit and noise reduction technique as a function of source impedance value especially for a seat mounted sensor.

Humidity sensors used in automatic windshield defogging controls contribute to the improvement of fuel consumption. The optimum control of air conditioning systems can be realized by adding humidity information to conventional systems which have used only temperature information. While resistive humidity sensors have been widely used, their sensing range and responsiveness are observed as issues. Resistive sensors cannot function at a humidity range of around 100% RH as well as at a low temperature range, and have a low response rate to sudden changes in humidity. It is considered that resistive humidity sensors will be replaced with capacitive ones which have a wide sensing range and high responsiveness.

It has been reported that the middle range of gasoline distillation temperatures strongly affects vehicle driveability and exhaust hydrocarbon (HC) emissions, and that MTBE(CH3-O-C4H9)- blended gasoline causes poor driveability during warm-up. The present paper is concerned with the results of subsequent detailed research on gasoline characteristics, exhaust emissions and driveability. In this paper, first it is demonstrated by using four models of passenger cars having different types of exhaust gas treatment system that decreased 50% distillation temperature (T50) reduces exhaust HC emission. This result indicates lowering T50 in the market will contribute to improving air quality. Secondly gasoline behavior in the intake manifold is investigated by using an engine on the dynamometer in order to clarify the mechanisms of HC emission increase and poor engine response which are caused by high T50.

Direct injection gasoline engines require extremely advanced control of air-fuel mixture in order to achieve good stratified combustion. The method of examining quality of mixture formation in combustion chambers is essential for the achievement. In this research, air-fuel mixture in combustion chamber of the TOYOTA D-4 engine was analyzed in space and time by visualization as well as Air/Fuel ratio measurement by multi-point and high response techniques. Thus the effects that injection timing, swirl and fuel pressure exerted to mixture formation were elucidated.

An ignition simulation and an ignition visualization method that analyze effects of spark plug electrode design have been developed. In the ignition simulation, a programmed heat source corresponds to the discharge energy in the spark gap, and the flame-kernel generation and flame propagation are calculated on the heat balance in the gap, in consideration of thermal transmission to the electrodes. The results by this simulation indicate that high ignitability of fine ground electrode spark plugs is because the miniaturization of the ground electrode reduces the heat loss, and flame growth is thus less disturbed by the loss. The ignition visualization includes taking Schlieren images by laser light to capture flame kernels with weaker luminescence intensity compared to ignition discharge spark luminescence. This visualization enables the observation of the influence of the shape of spark plug electrodes on flame growth.

To better estimate soot loadings from the pressure drop of diesel particulate filters (DPFs), a new concept cordierite-based catalyzed DPF has been developed. This new catalyzed DPF features (1) no washcoat layer, which often is the origin of uncertain pressure drop behavior, and (2) a modified substrate composition for improved thermal durability of the catalyst metal without the washcoat layer. Several characteristic were confirmed through engine tests based on this concept.

In recent years, CO2 emission constraint has been strengthened worldwide in order to fight global warming, and it is believed that the demand for compact and energy-saving car will be increasing year after year. On the other hand, larger interior space of vehicle to as-sure passenger comfort is demanded, so that the car air-conditioner is required to be smaller and energy saving efficient further more. Therefore, we have developed the new type of compact high-efficiency blower fan for compact car air-conditioning system (HVAC). Because of the requirements that the blower fan to be not only small size but energy-saving and low noise efficient, we started this development by modifications for basic blower fan internal air flow system of existing products. Generally, Sirocco fan, which is compact and able to supply high pressure, is often adopted for blower to be used for car air-conditioner.

In order to evaluate the toughness of automotive ECU's to electrostatic discharge, a conventional method where electrostatic discharge pulse is applied to connector parts on a printed circuit board is commonly used. But quantitative re-designing principles to improve the static electricity tolerance have not been made clear that completely utilizes the test data shown below till now, because propagation mechanism of static electricity on a circuit board is not clear. This paper describes the ESD current measurement technique which detects the near magnetic field generated by ESD currents. We developed to measure the ESD currents using the new loop antenna on a circuit board. The ESD current, was generated with the static electricity applied to a model circuit pattern in conformity with IEC and ISO standard and measured using the antenna. Also it was able to visualize how static electricity energy would propagate through the circuit board.

In vehicle control systems such as ABS (anti-lock braking system) or active suspension control, sensors for detecting longitudinal and/or lateral acceleration of vehicles (acceleration of up to ± 9.8 m/s2, with frequency range of DC to 20 Hz) is necessary. The principle of acceleration detection for this sensor is as follows. A permanent magnet levitates steadily in magnetic fluid by the action of the magnetic field generated by the magnet itself. The magnet moves by the application of acceleration on the mass of the magnet. This change of position of the magnet is detected by the Hall element, and thus acceleration is measured as an electrical signal. This sensor consists of only magnetic fluid, a permanent magnet, housing, a pair of Hall elements and an electronic circuit.

The coming Diesel powertrains will remain as key technology in Europe to achieve the stringent 2025 CO2 emission targets. Especially for applications which are unlikely to be powered by pure EV technology like Light Duty vehicles and C/D segment vehicles which require a long driving range this is the case. To cope with these low CO2 targets the amount of electrification e.g. in form of 48V Belt-driven integrated Starter Generator (BSG) systems will increase. On the other hand the efficiency of the Diesel engine will increase which will result in lower exhaust gas temperatures resulting in a challenge to keep the required NOx reduction system efficiencies under Real Drive Emissions (RDE) driving conditions. In order to comply with the RDE legislation down to -7 °C ambient an efficient thermal management is one potential approach. Commonly utilized means to increase exhaust gas temperature are late injection and/or intake throttling, which enable sufficient NOx reduction efficiency.

In respect to the present large refrigerator trucks, sub-engine type is the main product, but the basic structure does not change greatly since the introduction for around 50 years. A sub-engine type uses an industrial engine to drive the compressor, and the environmental correspondence such as the fuel consumption, the emission is late remarkably. In addition, most of trucks carry the truck equipment including the refrigerator which consumes fuel about 20% of whole vehicle. Focusing on this point, the following are the reports about the system development plan for fuel consumption reduction of the large size refrigerator truck. New concept is to utilize electrical power from HV system to power the electric-driven refrigerator. We have developed a fully electric-driven refrigerator system, which uses regenerated energy that is dedicated for our refrigerator system.

A methodology for simulating effect of international variations in fuel compositions on spray combustion is proposed. The methodology is validated with spray combustion experiments with real fuels from three different countries. The compositions of those fuels were analyzed through GC×GC and H-NMR. It was found that ignition delay times, flame region and flame luminosity were significantly affected by the compositional variations. For the simulation, an evaporation surrogate consisting of twenty two species, covering basic molecular types and a wide range of carbon numbers, is developed. Each species in the evaporation surrogate is then virtually converted to a reaction surrogate consisting of n-hexadecane, methylcyclohexane and 1,2,4-trimethyl benzene so that combustion reactions can be calculated with a published kinetic model. The virtual species conversion (VSC) is made so as to take over combustion-related properties of each species of evaporation surrogates.

In automobiles, Integrated Starter Generators (ISGs) are important components since they ensure significant fuel economy improvements. With motors that operate at high voltage such as ISGs, it is important to accurately know partial discharge inception voltages (PDIVs) for the assured insulation reliability of the motors. However, the PDIVs vary due to various factors including the environment (temperature, atmospheric pressure and humidity), materials (water absorption and degradation) and voltage waveforms. Consequently, it is not easy either empirically or analytically to ascertain the PDIVs in a complex environment (involving, for example, high temperature, low atmospheric pressure and high humidity) in which many factors vary simultaneously, as with invehicle environments. As a well-known method, PDIVs can be analyzed in terms of two voltage values, which are the breakdown voltage of the air (called “Paschen curve”) and the shared voltage of the air layer.