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Reduction of greenhouse gases or CO2 is the global issue for sustainability. City of Yokohama, where 3.7 million people live, established the Yokohama Climate Change Action Policy “CO-DO30”, aiming to cut down on greenhouse gas emissions by over 30% per person by 2025, and by over 60% by 2050. “CO-DO30” includes 7 areas of approaches, such as Living, Businesses, Buildings, Transportation, Energies, Urban and Green, and City Hall. To achieve this challenging target, practical and effective action on transportation area is definitely required, because it emits 20% of total greenhouse gas emission in the city. In 2008, City of Yokohama and Nissan jointly started YOKOHAMA Mobility “Project ZERO” (YMPZ), a 5-year project aimed at realizing “Eco-Model City, Yokohama”.

This paper describes a new approach to solving various problems inherent in conventional multiplexed wiring systems. These problems include the fact that the quantity of cut leads, which determines the cost, is not reduced even though the bulk of the wire harness is decreased. Another problem is that the communications system has a very complex configuration. With the approach proposed here it has been found that the number of cut leads can be reduced by housing the communications circuits individually in each piece of electrical equipment. This can be accomplished by grouping together the wiring in which the signals activating electrical load units all flow in the same direction. Custom LSI circuits have been developed to simplify the communications circuits. All of these developments have been combined into practical multiplexed wiring systems for controlling the power Windows, automatic door locks and power seats.

In our new fuel injection method, the injector for each cylinder is triggered twice per combustion cycle. The first injection is triggered as early as possible to obtain a good fuel mixture quality. The second injection is triggered as late as possible and as close to the intake valve opening so as to obtain a constant air-fuel ratio even during rapid acceleration. Furthermore, in order to prevent, misfire, timing is calculated based on the fuel amount when the fuel injection occurs. Driveability is improved over a wider range of driving conditions while maintaining good fuel economy and omission control.

This paper describes a multiplexed communication protocol matched to vehicle diagnosis, which has become more complicated due to the greater sophistication of Electronic Control Units (ECUs). The diagnostic data link must be both flexible enough for complex applications and economical enough for most ECUs. First, an asynchronous communication method controlled by an external clock, one function of a CPU with UART, is employed to minimize ECU hardware cost. Second, a polling/selecting method comprising a set of diagnostic commands and a practical data link procedure is developed to minimize the ECU software burden. The result is a cost effective, easy-to-protocol.

Nissan has recently developed and begun driving tests of a fuel cell vehicle equipped with a methanol reformer that produces hydrogen through the use of a catalyst to induce chemical reactions between methanol and water. With this onboard fuel cell system, only methanol in the form of a liquid fuel needs to be supplied, making the system highly practical as an automotive powertrain for near-future application. The Nissan Fuel Cell Vehicle (FCV) adopts a high-efficiency neodymium magnet synchronous traction motor combined with lithium-ion batteries that enable the vehicle to achieve optimum electric power by switching between a fuel cell-powered driving mode and a battery-powered driving mode. This presentation will cover the current status of the FCV development program and driving test results.

The authors have developed a steering entropy method to easily and accurately quantify the workload imposed on drivers who are engaged in activities apart from the normal driving operations of longitudinal and lateral control. A driver's steering behavior tends to become more discontinuous while performing an activity in addition to driving. To quantify these discontinuities, steering entropy values are obtained from a time-series history of steering angle data. A special-purpose driving simulator and a test procedure have been developed that allow workload evaluations to be conducted efficiently. The simulator and test procedure were used to evaluate the additional workload incurred by 14 different types of activities. The steering entropy results were compared with a dual task method as well as a subjective evaluation method.