The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) started a project for next generation Environmentally Friendly Vehicles (EFVs) in fiscal 2002 and entrusted implementation of the project to the National Traffic Safety and Environment Laboratory (NTSEL), an independent administrative institution.
In this report, the authors explain the project outline including its objectives, an implementation framework, development targets for environmental performance, features of each of the developed EFVs, and so on. The project has been carried out by NTSEL acting as a principal research agency conducting close cooperation with automobile manufacturers, parts manufacturers, universities, and fuel manufacturers. Various types of heavy duty EFVs such as CNG/LNG trucks, DME trucks, hybrid vehicles including IPT power supply system, FTD trucks, a super clean diesel engine, a hydrogen combustion engine and so on, were developed in the project. The design concepts, new technologies and environmental performances of those EFVs are described in this report.

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Nissan has developed a neutral idle control system to improve the fuel economy of the small 4-cylinder 1.5-liter petrol engine (HR15DE) and XTRONIC CVT, which were released in 2004. The system improves fuel economy when idling by using more accurate control for the forward clutch and integrated control for the engine and the CVT. As a result, Nissan has improved vehicle fuel economy by 20% with respect to the standard set in the fuel economy regulations for fiscal year 2010.

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In this paper, spray structure mechanisms are described and the important factors for calculating diesel spray using LES are described, such as computational grid resolution, convective scheme and spray models. Furthermore, visualization of spray and vortex structure for LES spray simulation is conducted. Results indicate that spray droplets are distributed around a three-dimensional vortex structure composed of many hairpin vortexes. Results also suggest that the three-dimensional spray structure is influenced by a three-dimensional vortex structure developed in the ambient gas.

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The purposes of the present study are to develop the ultrasonic flowmeter measuring directly the exhaust gas flowrate. The digital signal processing was improved toward practical use and its evaluation test was carried out. The validation tests of the developed high-temperature ultrasonic flowmeter were performed with the exhaust gas flow simulator, in order to demonstrate its possibility, and its effectiveness was surely confirmed.

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From an energy security and CO2 reduction point of view, much attention has been given to biofuels. Yet, the major challenge in combusting high concentration ethanol fuel(E85) in SI engines is to retain stable cold startability and emission performance. This is due to the large latent heat required to vaporize ethanol. In this Paper, evaporation of high concentration ethanol fuel at cold temperatures is analyzed quantitatively

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A permanent magnet DC brushless motor is the most suitable for high torque electric power steering. Unlike brush motors, these motors can be driven up to high revolution speeds by using field weakening control that reduces the magnetic flux. However, vibration caused by this field weakening control occurs in an 8-pole 9-slot DC brushless motor. Therefore, the issue is that high power and low vibration must be compatible. The authors focused on this issue, and investigated the mechanism of the vibration. This paper proposes a countermeasure based on the results of this investigation, and reports test results of reduced vibration.

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In the present study, the brush model is reanalyzed and algebraic equations are derived for use in estimating tire grip margin. Application of this estimation method allows the tire force distribution of a four-wheel independent steering (4WIS) vehicle to be optimized by using the objective function of the maximum value of the μ-rate, which is defined as the tire force normalized by the radius of the friction circle. We later discuss a protection function that was inspired by the limiters used in fly-by-wire aircrafts. This function prevents excessive steering command inputs to the vehicle controller. The numerical simulation results obtained using CarSim prove the basic functionalities of both methods.

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The octane number requirement (ONR) for recent gasoline vehicles in Japan has been surveyed using a primary reference fuel (PRF) for octane number measurement and a commercial type fuel (CTF). The ONR for regular gasoline recommended vehicles has hardly changed since 1997, but the ONR for premium gasoline recommended vehicles has slightly increased. The ONR measured with the PRF, which has zero sensitivity (RON-MON=0), and that measured by the CTF with a high sensitivity for 1997 to 1999 model year vehicles are quite similar in terms of RON. On the other hand, the ONR measured with the PRF is smaller than that measured with the CTF for 2006 model year vehicles, which shows that MON also affects the ONR of recent vehicles.

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The authors of this report have proposed "Judgment Line of Brake Initiation" in phase plane of the index (KdB_c) and the gap (D or distance). It was determine by a test driver's brake initiation in moderate danger levels. The experiments with several subjects in a proving ground (a test course) were conducted and differences among individuals were recognized. In this paper, a method to adapt "Judgment Line of Brake Initiation" to individual drivers in public roads is proposed.

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On-board measurement systems with an exhaust gas analyzer were installed on test vehicles, and road tests to analyze the correlation between environmental factors such as the gradient of the road and traffic flow and emission increase. Based on this data, the mechanisms increasing NOx from vehicles driving at specific spots such as downward slopes, sharp curves and so on were verified by the catalyst model presented in this paper to understand the catalyst reaction atmosphere by numerical analysis of A/F fluctuation. Furthermore, effective pollution abatement measures were investigated for the hot spot NOx emission increases using our catalyst model.

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In reaction to the increasing shift from larger vehicles to smaller crossovers as a result of the rising price of oil, Nissan has developed a brand new small crossover called the Rogue for the extremely competitive US market. Sales of the ROGUE began in September 2007, and feedback from the market has been quite positive. This report describes an outline of the ROGUE and its targets.

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