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The energy crisis and rising gas price in the 2000s led to a growing popularity of hybrid vehicles. Hyundai-Kia Motors has been challenging to develop the new efficient eco-technology since introducing the mild type compact hybrid electric vehicle for domestic fleet in 2004 to meet the needs of the increasing automotive-related environmental issues. Now Hyundai has recently debuted a full HEV for global market, Sonata Hybrid. This system is cost effective solution and developed with the main purpose of improving fuel consumption and providing fun to drive. Presenter Seok Joon Kim, Hyundai Motor Company

After the turn of the century, growing social attention has been paid to environmental concerns, especially the reduction of greenhouse gas emissions and it comes down to a personal daily life concern which will affect the purchasing decision of vehicles in the future. Among all the sources of greenhouse gas emissions, the transportation industry is the primary target of reduction and almost every automotive company pours unprecedented amounts of money to reengineer the vehicle technologies for better fuel efficiency and reduced CO2 emission. Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

This paper describes the methods adopted to improve the image quality of the all-around view system. This system uses multiple vehicle-mounted cameras to capture images of the circumstances around the vehicle. The images undergo viewpoint transformation and are synthesized to create a single image seen from a virtual perspective overhead. The specific methods discussed here concern optimization of the design parameters for the camera orientation and a camera calibration method that does not involve physical movement of the cameras.

In recent years, catalyst systems such as a lean NOx trap (LNT) catalyst system and a urea selective catalytic reduction (SCR) system have been developed to obtain cleaner diesel emissions. At Nissan, we developed an emission control system for meeting Tier 2 Bin 5 requirements in 2003. On the basis of that technology, a new HC-NOx trap catalyst system has now been developed that complies with the SULEV standards without increasing the catalyst volume and precious metal loading. Compliance with the SULEV standards requires a further reduction of HC (NMHC) emissions by 84% and NOx by 60% compared with the emission performance Tier 2 Bin 5 compliant catalyst system. Consequently high conversion performance for both HCs and NOx is needed. An investigation of HC emission behavior under the FTP75 mode showed that a reduction of cold-phase HCs was critical for meeting the standard. Large quantities of HCs above C4 are emitted in the cold state.

The aim of this study is to gain a better understanding of the mechanism of knocking with respect to flame propagation behavior based on 3D simulations conducted with the Universal Coherent Flamelet Model. Flame propagation behavior under the influence of in-cylinder flow was analyzed on the basis of the calculated results and experimental visualizations. Tumble and swirl flows were produced in the cylinder by inserting various baffle plates in the middle of the intake port. A comparison of the measured and calculated flame propagation behavior showed good agreement for various in-cylinder flow conditions. The results indicate that in-cylinder flow conditions vary the flame propagation shape from the initial combustion period and strongly influence the occurrence of knocking.

In 2006, Nissan began limited leasing of the X-TRAIL FCV equipped with their in-house developed Fuel Cell (FC) stack. Since then, the FC stack has been improved in cost, size, durability and cold start-up capability with the aim of promoting full-scale commercialization of FCVs. However, reduction of cost and size has remained a significant challenge because limited mass transport through the membrane electrode assembly (MEA) has made it difficult to increase the rated current density of the FC. Furthermore, it has been difficult to reduce the variety of FC stack components due to the complex stack configuration. In this study, improvements have been achieved mainly by adopting an advanced MEA to overcome these difficulties. First, the adoption of a new MEA and separators has improved mass transport through the MEA for increased rated current density. Second, an integrated molded frame (IMF) has been adopted as the MEA support.

In December 2006, Nissan announced its Nissan Green Program 2010 (NGP 2010), a mid-term environmental action plan that includes initiatives to reduce vehicle emissions. In line with this plan, the company intends to introduce a new and original hybrid system in fiscal year 2010. Specifically, this system-called the “Infiniti Direct Response Hybrid”-is a one-motor, two-clutch parallel hybrid system that eliminates the need for a torque converter. It will be featured in the 2012 Infiniti M35 Hybrid and provides the following advantages. 1 Significant improvement in fuel economy even in Highway driving 2 Better response and a more direct feeling 3 Lightweight and low cost This one-motor, two-clutch system without torque converter possesses a simple but highly capable architecture that is new to the passenger vehicle segment.

Traction control systems (TCSs) serve to control brake pressure and engine torque, thereby reducing driving wheel spin for improved stability and handling. Systems are divided into two basic types by the brake control configuration. One type is a one-channel left-right common control system and the other is a two-channel individual control system. This paper presents an analysis of these two types of TCS configurations in terms of handling, acceleration, stability, yaw convergence and other performance parameters. The systems are compared with and without a limited-slip differential (LSD) under various road conditions, based on experimental data and computer simulations. As a result of this work, certain Nissan models are now equipped with a new Nissan Traction Control System with a rear viscous LSD (Nissan V-TCS), which provides both the advantages of a rear viscous LSD in a small slip region and a two-channel TCS in a large slip region.

The use of CAE software in developing plastic components has advanced rapidly in recent years. This progress has been supported by the development of practical analytical tools, based on the finite element and boundary element methods, and on the dramatic improvements seen in computer performance. Following the introduction of a flow analysis program in 1982, Nissan has developed and implemented advanced programs for use in developing plastic components and has integrated the programs into a unified in-house system. This system is being utilized at the design and manufacturing stages of interior and exterior trim parts and has produced concrete results in different phases of component development. Work is now proceeding on the development of a system that can simultaneously analyze both the component performance and the factors that need to be considered in the manufacturing process.

To improve the fuel economy via high EGR, combustion stability is enhanced through the addition of hydrogen, with its high flame-speed in air-fuel mixture. So, in order to realize on-board hydrogen production we developed a fuel reformer which produces hydrogen rich gas. One of the main issues of the reformer engine is the effects of reformate gas components on combustion performance. To clarify the effect of reformate gas contents on combustion stability, chemical kinetic simulations and single-cylinder engine test, in which hydrogen, CO, methane and simulated gas were added to intake air, were executed. And it is confirmed that hydrogen additive rate is dominant on high EGR combustion. The other issue to realize the fuel reformer was the catalyst deterioration. Catalyst reforming and exposure test were carried out to understand the influence of actual exhaust gas on the catalyst performance.

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.

This paper describes a headway distance control system for platoon driving on an automated highway system (AHS). The system implemented on a test vehicle is described first, followed by a description of a vehicle control method based on the use of throttle and brake actuators. This method makes it possible to obtain the target acceleration and deceleration regardless of the vehicle speed range and the rate of acceleration or deceleration. Experimental and simulation results obtained with this method are presented. A control method is then described that uses inter-vehicle communication and laser radar to maintain a constant headway between vehicles. The results of simulations and driving tests conducted with three vehicles are presented to illustrate that the use of inter-vehicle communication is highly effective in improving headway control performance.

This paper describes the Multi-AV System featured in the 1989 model Nissan Cedric, Gloria, and CIMA. It is composed of a navigation system and an audio-visual system. The former system tracks the location of the vehicle and shows it on a CRT map display. This standalone navigation system has been achieved using a map-matching technique along with a terrestrial magnetic field sensor and wheel speed sensors installed at the wheels. Information on hotels, golf courses, Nissan dealers and other items can be obtained. A CD-ROM is employed as the memory. The audio-visual system consists of a radio, cassette deck, CD player, and TV. The Multi-AV System combines the practicality of a navigation function with the entertainment capabilities of an audio-visual system to satisfy diverse needs.

Ceramic honeycombs have been used as automotive catalyst supports in US, Japan, Europe and other highly urbanized countries. Now, engine output is a great concern for automanufacturers, and reduction of the wall thickness of honeycomb substrates became indespensable for maintenance of gas flow restriction to a certain low level. To reduce wall thickness, material should be strong to maintain canning strength of substrates. Mechanical strength was improved with high density cordierite. However, isostatic strength of whole substrates was still insufficient with reduced thin walls for canning in spite of the material's high mecanical strength. Discussion is carried out on further possibility of improving canning performance of thin wall substrates as well as flow restriction, and warm up characteristics.

ASICs (Application-specific ICs) offer one solution to the problems of quality, cost and installability associated with the increasingly larger-capacity Electronic Control Units (ECUs) in automobiles. A method was, therefore, created for designing automotive ASICs. Using the method, three ASICs were developed which, together, incorporate all of the functions of the electronic instrument cluster. The core ASIC contains the speedometer and system functions, and the other two ASICs contain the tachometer and gauge functions, respectively. This set of three ASICs allows an electronic instrument cluster design which is two times more reliable, and one-second the cost that conventional systems (with a micro-processor and discrete components).

This paper presents an improved exhaust emission simulation model that takes into account fuel transportation behavior in order to obtain more precise air-fuel ratio control, which is needed to meet stringent exhaust emission standards. This simulation model is based on experimental formulas for air and fuel behavior in the intake manifold, especially during transient engine operation. Fuel behavior, including the effect of wall flow on the air-fuel ratio, is obtained analytically. Predictions are then made of the exhaust emissions from a car operated under official driving schedules. The new simulation model is a useful tool in the design and development of fuel supply control systems. An outline of the new model is presented first along with a comparison of the calculated and experimental results. The air-fuel ratio control strategy derived with this model is then described.

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.

This paper describes an image processing method for recognizing white lines on the road ahead to accomplish automatic lane tracking. The behavior of detected points on the white lines can be regarded as multi-channel time-series data. The stochastic behavior of each point correlates with not only its own past behavior but also the behavior of other points around it. Behavior is identified by using a multi-variable auto-regressive (AR) model. This method can estimate the road configuration ahead logically even if the points cannot be detected clearly because a line is discontinuous or is hidden by a forward vehicle.

In the past few years, car navigation and cellular phone system are rapidly increased in Japan and vehicle information and communication system (VICS), the public traffic information service started in 1996, accelerates realization of ITS world. This rapid movement causes drivers to want more information on not only traffic jam but also other versatile items like parking availability, weather report and the latest news, etc. via cellular phone network. This paper describes the on-demand information service with the interactive human interface by operators and the development of the information center and the in-vehicle system to realize it.

From the beginning of the 1990s, we have been vigorously investigating a high-performance power source system for application to environmental vehicles, focusing our research and development efforts specifically on lithium-ion batteries. In order to adapt a battery system to the requirements of the target vehicle, battery performance must be predicted and designed more accurately. In the case of hybrid electric vehicles, for example, battery power must be reliably assured. Improving battery power requires quantitative analytical methods as fundamental techniques for understanding the basic processes that take place in a battery. From this perspective, we began constructing a battery simulation model from scratch in the middle of the 1990s concurrently with our battery R&D activities. The model simulates electrode reactions and charge transport and has been used in investigating the influence of these factors on battery performance.