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There are two primary technical issues in the application of position sensorless control to generators for 100% electric-drive hybrid vehicles. The first is the risk of losing control when position sensorless estimation methods are changed in accordance with the generator speed, while. The second is the reduction in the maximum torque if the rate of change in the generator speed is extremely large in a relatively low-rotation-speed area. This study proposes countermeasures for each issue and their effects examines them via simulations and experiments.

Road Noise is generated by the change of random displacement input inside the tire contact patch. Since the existing 3 or 6 directional electromagnetic shakers have a flat surface at the tire contact patch, these shakers cannot excite the vehicle in a manner representative of actual on-road road noise input. Therefore, this paper proposes a new experimental method to measure the road noise vehicle transfer function. This method is based on the reciprocity between the tire contact patch and the driver's ear location. The reaction force sensor of the tire contact patch is newly developed for the reciprocal loud speaker excitation at the passenger ear location. In addition, with this equipment, it is possible to extract the dominant structural mode shapes creating high sound pressure in the automotive interior acoustic field. This method is referred to as experimental structure mode participation to the noise of the acoustic field in the vibro-acoustic coupling analysis.

A flag is a global boolean variable used to achieve synchronization between various tasks of an embedded system. An application implementing flags performs actions or events based on the value of the flags. If flag variables are not implemented properly, certain synchronization related issues can arise which can lead to unexpected behavior or failure of the underlying system. In this paper, we present an automated verification technique to identify and verify flag usage patterns at an early stage of code development. We propose a two-step approach which consists of: a. identification of all potential flag variables and b. verification of flag usage patterns against predefined set of rules. The results of our experiment demonstrate that the proposed approach reduces the cost and complexity of the flag review process by almost 70%.

This paper describes the development of the drive motor adopted on the newly developed 2013 Model Year (MY) electric vehicle (EV). Based on the 2011MY EV that was specifically designed and engineered for mass-production, the 2013MY powertrain integrates the electric motor, inverter and charging system into one unit in order to achieve downsizing and weight saving, unlike previous 2011 model which had these components segregated. In general, integration of all components into one unit causes deterioration of the noise and vibration performance of vehicles due to an increase in weight and the number of resonance parts. In order to overcome such problems associated with this integration, each component in the 2013 model has been optimized to reduce noise and vibration resulting in high degree of vehicle quietness.

For diesel engine, lower compression ratio has been demanded to improve fuel consumption, exhaust emission and maximum power recently. However, low compression ratio engine might have combustion instability issues under cold temperature condition, especially just after engine started. As a first step of this study, cold temperature combustion was investigated by in-cylinder pressure analysis and it found out that higher heat release around top dead center, which was mainly contributed by pilot injection, was the key factor to improve engine speed fluctuation. For further understanding of combustion in cold condition, particularly mixture formation near a glow plug, 3D CFD simulation was applied. Specifically for this purpose, TI (Time-scale Interaction) combustion model has been developed for simulating combustion phenomena. This model was based on a reasonable combustion mode, taking into account the characteristic time scale of chemical reactions and turbulence eddy break-up.

Nissan LEAF that is a new model of an Electric Vehicle has dedicated IT system as standard equipment. Concept of this IT system, Services provided to owners and technical solutions to be introduced.

A variable compression ratio (VCR) technology, that has a new piston-crankshaft mechanism with multi links, has been patented and developed by Nissan for some years (This technology has been detailed in previous SAE paper 2003-01-0921 and 2005-01-1134). This paper will present the use of this VCR technology for Diesel engine. The objective set with the use of VCR for Diesel engine is mainly to reduce as much as possible engine out emission to prepare for long-term, more strict emission standards. Results presented will include the description of the 2l Diesel VCR engine and its VCR mechanism adapted to Diesel constraints. Combustion tests have been performed with the use of HCCI (Homogeneous Charge Compression Ignition) combustion. This technology is still in a research phase in Renault: the adaptation of VCR technology to a Diesel engine consists in the modification of several parts with the addition of lower links, control links and control shaft.

This paper presents a new method for calculating optical flow using data from a high frame-rate camera. We focused on a feature of image data captured with a high frame-rate camera in which objects do not move more than one pixel between successive frames. This approach eliminates repetitive processing for object identification among frames taken at different sampling times. High-speed processing hardware architecture was designed with sequential processing only, and the algorithm was implemented in a field programmable gate array. The resultant unit can calculate optical flow for a 640×120 pixel size image with a 480-Hz processing cycle and 0.5-μsec processing latency.

In order to clarify future automobile technologies and fuel qualities to improve air quality, second phase of Japan Clean Air Program (JCAPII) had been conducted from 2002 to 2007. Predicting improvement in air quality that might be attained by introducing new emission control technologies and determining fuel qualities required for the technologies is one of the main issues of this program. Unregulated material WG of JCAPII had studied unregulated emissions from gasoline and diesel engines. Eight gaseous hydrocarbons (HC), four Aldehydes and three polycyclic aromatic hydrocarbons (PAHs) were evaluated as unregulated emissions. Specifically, emissions of the following components were measured: 1,3-Butadiene, Benzene, Toluene, Xylene, Ethylbenzene, 1,3,5-Trimethyl-benzene, n-Hexane, Styrene as gaseous HCs, Formaldehyde, Acetaldehyde, Acrolein, Benzaldehyde as Aldehydes, and Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene as PAHs.

Diesel emissions are significant issue worldwide, and emissions requirements have become so tough that. the application of after-treatment systems is now indispensable in many countries To meet even more stringent future emissions requirements, it has become apparent that the improvement of market fuel quality is essential as well as the development in engine and exhaust after-treatment technology. Japan Clean Air Program II (JCAP II) is being conducted to assess the direction of future technologies through the evaluation of current automobile and fuel technologies and consequently to realize near zero emissions and carbon dioxide (CO2) emission reduction. In this program, effects of fuel properties on the performance of diesel engines and a vehicle equipped with two types of diesel NOx emission after-treatment devices, a Urea-SCR system and a NOx storage reduction (NSR) catalyst system, were examined.

Nissan Motor has put on the European SUV market a 2.2-L direct-injection diesel engine with a diesel particulate filter (DPF) system that complies with the EURO IV emission regulations. This paper describes the DPF system, cooperative control of a variable geometry turbo (VGT) and exhaust gas recirculation (EGR), and a high-accuracy lambda control adopted for this engine. In order to achieve a compact DPF, the high-accuracy lambda control was developed to reduce variation in engine-out particulate matter (PM) emissions. Moreover, the accuracy of the technique for predicting the quantity of PM accumulation was improved for reliable detection of the DPF regeneration. Prediction error for PM accumulation increases during transient operation. Control logic was adopted to correct the PM prediction according to lambda fluctuation detected by an observer for lambda at cylinder under transient operating conditions. The observer is corrected lambda sensor output.

Emission regulations for diesel-powered vehicles have been gradually tightening. Installation of after-treatment devices such as diesel particulate filters (DPF), NOx storage reduction (NSR) catalysts, and so on is indispensable to satisfy rigorous limits of particulate matter (PM) and nitrogen oxides (NOx). Japan Clean Air Program II Oil Working Group (JCAPII Oil WG) has been investigating the effect of engine oil on advanced diesel after-treatment devices. First of all, we researched the impact of oil-derived ash on continuous regeneration-type diesel particulate filter (CR-DPF), and already reported that the less sulfated ash in oil gave rise to lower pressure drop across CR-DPF [1]. In this paper, impact of oil-derived sulfur and phosphorus on NSR catalyst was investigated using a 4L direct injection common-rail diesel engine with turbo-intercooler. This engine equipped with NSR catalyst meets the Japanese new short-term emission regulations.

Impact of oil-derived ash on the pressure drop of continuous regeneration-type diesel particulate filter (CR-DPF) was investigated through 600hrs running test at maximum power point on a 6.9L diesel engine, which meets the Japanese long-term emission regulations enacted in 1998, using approximately 50ppm sulfur content fuel. Sulfated ash content of test oils were varied as 0.96, 1.31, and 1.70 mass%, respectively. During the running test, the exhaust pressure drop through CR-DPF was measured. And after the test, the ventilation resistance through CR-DPF was also evaluated before and after the baking process, which was applied to eliminate the effect of soot accumulated in CR-DPF. The results revealed that the less sulfated ash in oil gave rise to lower pressure drop across CR-DPF. According to microscope examination of the baked DPF, ash was mainly accumulated on the wall surface of CR-DPF, and that seemed to be related to the magnitude of pressure drop caused by ash.

Experimental investigations were previously conducted with a direct-injection diesel engine with the aim of reducing exhaust emissions, especially nitrogen oxides (NOx) and particulate matter (PM). As a result of that work, a combustion concept, called Modulated Kinetics (MK) combustion, was developed that reduces NOx and smoke simultaneously through low-temperature combustion and premixed combustion to achieve a cleaner diesel engine. In subsequent work, it was found that applying a low compression ratio was effective in expanding the MK combustion region on the high-load side. The MK concept was then combined with an exhaust after-treatment system and applied to a test vehicle. The results indicated the attainment of ULEV emission levels, albeit in laboratory evaluations. In the present work, the combination of the MK combustion concept and certain fuel properties has been experimentally investigated with the aim of reducing exhaust emissions further.

Recently tailored blank sheets are widely and very often applied to car body's panels in order to reduce weight and number of automobile parts. The tailored blank sheets are produced by welding more than two metal sheets. The gap between edges of blank sheets before laser welding should be controlled for obtaining good quality tailored blank sheets. Therefore control of gap within 0.1mm between batting two blank sheets for production is one of main subjects for producing tailored blank sheets. This report presents not only a new mechanism on gap control but also a development of Finite Element Method (FEM) analysis for prediction of gap. The new mechanism has been applied successfully to produce good quality tailored blank sheets. The gap prediction simulation can reduce the time for gap control apparatus design.

Diesel engines have attracted more attention in recent years as one means of reducing carbon dioxide (CO2) emissions from motor vehicles. One of the major issues for diesel engines is exhaust emissions performance. Diesel engines also face various difficulties in providing the driving force demanded by the driver because of their greater inertia than that of gasoline engines. Meanwhile, continuously variable transmissions (CVTs) have been popularized as gearboxes that execute ratio changes continuously without generating shift shock. The aim of this research is to achieve higher levels of drivability and exhaust emissions performance by mating a CVT to a diesel engine and making maximum use of the continuous ratio change capability. An integrated engine-CVT control algorithm that can freely set the driving force and also the engine operating conditions for generating that driving force has been developed through this study.

Experimental investigations were conducted with a direct-injection diesel engine to improve exhaust emission, especially nitrogen oxide (NOx) and particulate matter (PM), without increasing fuel consumption. As a result of this work, a new combustion concept, called Modulated Kinetics (MK) combustion, has been developed that reduces NOx and smoke simultaneously through low-temperature combustion and premixed combustion, respectively. The characteristics of a new combustion concept were investigated using a single cylinder DI diesel engine and combustion photographs. The low compression ratio, EGR cooling and high injection pressure was applied with a multi-cylinder test engine to accomplish premixed combustion at high load region. Combustion chamber specifications have been optimized to avoid the increase of cold-start HC emissions due to a low compression ratio.

There have been strong demands recently for reductions in the fuel consumption and exhaust emissions of diesel engines from the standpoints of conserving energy and curbing global warming. A great deal of research is being done on new emission control technologies using direct-injection (DI) diesel engines that provide high thermal efficiency. This work includes dramatic improvements in the combustion process. The authors have developed a new combustion concept called Modulated Kinetics (MK), which reduces smoke and NOx levels simultaneously by reconciling low-temperature combustion with pre-mixed combustion [1, 2]. At present, research is under way on the second generation of MK combustion with the aim of improving emission performance further and achieving higher thermal efficiency [3]. Reducing heat rejection in the combustion chamber is effective in improving the thermal efficiency of DI diesel engines as well as that of MK combustion.

Technologies applied to the Nissan Tino Hybrid, marketed in March 2000, in Japan, are expected to evolve into the core powertrain technologies of the future, for the following technical advantages inherent to hybrid EVs: 1 Regeneration of deceleration energy 2 Motor driven propulsion at low speed, combined with power-assisted operation in the mid- and high-load ranges. It is expected that a number of models will be introduced to the market in the future, which pursue these advantages in various forms, resulting in HEV technologies to accelerate the use of electric power for the vehicle. Fuel cell vehicles will be included in this future scenario. In this paper, our view on the future HEV technologies will be described. In addition, the latest technologies applied to the Nissan Tino Hybrid will be introduced.

This paper deals with the development of plastics recycling technology, which is one key to resolving environmental and natural resource problems and encouraging recycling activities. Bumpers are among the heaviest plastic auto parts, so the technology for recycling bumpers is strongly required. Paint remaining on bumpers causes the strength of the recycled material to decline and degrades its surface quality. Therefore, unless the paint is removed, it is impossible to use recycled material to manufacture new bumpers. This hampers recycling efforts and results in low-value recycled material. Consequently, it is essential to develop a simple paint removing without chemical substances for practical plastics recycling at low cost. Two topics are discussed in this paper. The first concerns the mechanism of paint removal and the development of a technique for utilizing that mechanism.