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This paper describes the development of a vehicle with four-wheel steering in which the rear wheels can be controlled electronically in addition to the conventional front-wheel steering system. In the method for steering the rear wheels, the side-slip angle at the vehicle's center of gravity is maintained at zero, which improves the basic dynamic properties of the vehicle. This approach allows greater maneuverability at low speed by means of counter-phase rear steering and improved stability at high speed through same-phase rear steering. However, the use of counter-phase rear steering to improve maneuverability gives rise to problems in regard to practicality. In addition, continuously controlled four-wheel steering, using counter-phase at low speed and same-phase at high speed, leads to many other problems regarding practicality because of the strong apparent understeer characteristics.

The new Nissan 1.7 liter 4 cylinder diesel engine has been developed to meet the social requirements for energy conservation. The main objective was to improve fuel economy without sacrificing driveability, and this has been achieved by minimizing engine weight, reducing mechanical friction loss and optimizing the combustion system. The CA series gasoline engine, which is known for its light weight, was chosen as the base engine for dieselization. The swirl chamber combustion system used for the LD28 engine was modified to satisfy the requirements for high power, good fuel economy and low noise. Engine noise has been reduced with the aid of several analytical methods such as laser holography. Special attention has been paid to the reduction of diesel knock which is most offensive to the ear. To install this engine in a small FWD vehicle transversely, much effort went into the minimizing of the engine length and width.

The SKY Project (Start ITS from Kanagawa, Yokohama) was launched in October 2004 in Yokohama, Japan in order to contribute to the local community by reducing traffic accidents and congestion. SKY is a private sector collaboration between Nissan Motor Co., Ltd., NTT DoCoMo, Inc., Panasonic Corporation, and Xanavi Informatics Corporation (now Clarion Ltd.). Support has also been provided from the public sector, namely the National Police Agency of Japan (NPA) and the Kanagawa Prefectural Police. Through the use of in-vehicle technology and an Intelligent Transportation Systems (ITS) that communicates with the infrastructure, information on nearby vehicles and the surrounding traffic environment can be utilized to reduce traffic accidents, shorten travel times, and increase fuel savings. These are the goals of the SKY project. This paper shows the results of early stage testing and the introduction of newly started trials.

This paper describes a low-cost 48 × 48 element thermal imaging camera intended for use in measuring the temperature in a car interior for advanced air conditioning systems. The compact camera measures 46 × 46 × 60 mm. It operates under a program stored in the central processing unit and can measure the interior temperature distribution with an accuracy of ±0.7°C in range from 0 to 40°C. The camera includes a thermoelectric focal plane array (FPA) housed in a low-cost vacuum-sealed package. The FPA is fabricated with the conventional IC manufacturing process and micromachining technology. The chip is 6.5 × 6.5 mm in size and achieves high sensitivity of 4,300 V/W, which is higher than the performance reported for any other thermopile. This high performance has been achieved by optimizing the sensor's thermal isolation structure and a precisely patterned Au-black absorber that attains high infrared absorptivity of more than 90%.

With technological breakthroughs in electric land vehicles revolutionizing their respective industry, maintenance, repair, and overhaul (MRO) facilities in aviation are also adopting digital technologies in their practices. But despite this drive towards digitalization, the industry is still dominated by manual labor and subjective assessments. Today, several technologies, processes, and practices are being championed to resolve some of these outstanding challenges. Considering this, it is important to present current perspectives regarding where the technology stands today and how we can evaluate capabilities for autonomous decision support systems that prescribe maintenance activities. Overlooking some of these unsettled domain issues can potentially undermine any benefits in speed, process, and resilience promised by such systems.

Our study unveils what smart cars are needed to minimize congestion by traffic stability. We have previously considered pacer cars with single lane road networks based on a car following model, e.g. adaptive cruise control (ACC). However, pacer cars may have a limitation with multi-lane roadways in terms of lane distribution of traffic and shockwave suppression. Therefore, we motivate building a new smart car which extends the capability of pacer cars allowing lane changing at the timing of congestion detection. In essence, the congestion detection plays a role of adjusting the (time) headway of smart cars to determine whether lane changes should be undertaken. Lane changes can be used to uniformize (or equalize) lane distribution for traffic (flow) stability. Our simulation study has suggested that the proposed smart cars enforce the capability of traffic stability more than manual and pacer cars.

To reduce quenching distortion, step gas quenching has been proposed in recent years, which refers to rapid gas cooling of steel from austenitizing temperature to a point above or below Ms temperature, where it is held for a specific period of time, followed by gas cooling. In this study, by using infrared thermography combined with conventional thermocouple, a new temperature monitoring and control system was developed to realize the step gas quenching process of a hypoid ring gear after low pressure carburizing. The test production results indicate that by using the new monitoring and control system, we can control the gas quenching process and the distortion of carburized gear treated by step gas quenching can be reduced significantly compared with standard gas quenching.

This paper describes a system for measuring unsteady pressure at up to 256 spatial points and at frequencies up to 300 Hz. The system consists of commercially available equipment for measuring steady pressures. It is based on the use of electronically scanned pressure (ESP) sensors, 16 A/D converters, and a personal computer to control the whole system and acquire data. The signal outputs through the tubes connecting the pressure taps and the ESP sensors are compensated, as are the phase delays between the scanned signals and the gain variation. A 1/5 scale model of a sedan was used in this experiment. The passenger car model was placed in a wind tunnel equipped with a moving belt, which was operated at the same speed as the uniform flow in the wind tunnel. Pressure measurements were obtained at 252 points in a plane behind the model perpendicular to the uniform flow. Measurements were made with the belt turned on and off.

This paper describes an integrated switch system by which the audio control system, air-conditioner control system and navigation control system can be operated with a smaller number of switches. This system resolves several issues resulting from the incorporation of information technology into vehicles, including the increased visual load due to the greater amount of information presented and the poorer operability resulting from increased functionality. A usability evaluation was conducted and the results indicated that the integrated switch system can reduce visual load.

Wireless Power Transfer (WPT) promises automated and highly efficient charging of electric and plug-in-hybrid vehicles. As commercial development proceeds forward, the technical challenges of efficiency, interoperability, interference and safety are a primary focus for this industry. The SAE Vehicle Wireless Power and Alignment Taskforce published the Recommended Practice J2954 to help harmonize the first phase of high-power WPT technology development. SAE J2954 uses a performance-based approach to standardizing WPT by specifying ground and vehicle assembly coils to be used in a test stand (per Z-class) to validate performance, interoperability and safety. The main goal of this SAE J2954 bench testing campaign was to prove interoperability between WPT systems utilizing different coil magnetic topologies. This type of testing had not been done before on such a scale with real automaker and supplier systems.

In order to significantly reduce NOx levels by EGR (Exhaust Gas Recirculation), while maintaining good fuel economy and driveability, the EGR flow rate must be properly and accurately controlled under a variety of engine operating conditions. Toward this objective, a new EGR control system was developed. It utilizes a carburetor venturi vacuum for a stable reference signal that represents the engine operating condition and it controls the EGR flow rate by using a feedback principle to obtain sufficient flexibility compatible with several different engines. Its control characteristics were mathematically analyzed. And it has also been confirmed that the system can automatically compensate for the drift in EGR characteristics. This EGR control system has been utilized in Nissan’s emission control systems in order to comply with the 1978 Japanese Emission Standards and the 1980 U.S. Federal and California Emission Standards.

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%.