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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

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.

A multiple-link variable compression ratio (VCR) mechanism is suitable for a long-stroke engine by providing the following characteristics: (1) a nearly symmetric piston stroke and (2) an upper link that stays vertical around the time of the maximum combustion pressure. These two characteristics work to reduce force inputs to the piston. The maximum inertial force around top dead center is reduced by the effect of the first characteristic. The second characteristic is effective in reducing piston side thrust force and helps ease piston pin lubrication. Because of the combined effect of these characteristics, the piston skirt can be made smaller and the piston pin can be shortened. That makes it possible for the piston skirt and piston pin to move between the counterweights, resulting in a downward extension of the piston stroke. As a result, a longer-stroke engine mechanism can be achieved without making the cylinder block taller.

Nissan has developed a hydraulic active suspension which uses an oil pump as its power source to produce hydraulic pressure that negates external forces acting on the vehicle. As a result, the suspension system is able to control vehicle movement freely and continuously. This control capability makes it possible to provide higher levels of ride comfort and vehicle dynamics than are obtainable with conventional suspension systems. The major features of the hydraulic system include: (1) active bouncing control using a skyhook damper, (2) a frequency-sensitive damping mechanism and (3) active control over roll, dive and squat.

With SUVs and minivans accounting for a larger share of the US market in the past decade, rollover accidents have drawn greater attention, leading to more active research from different perspectives. This ranges from investigations for elucidating the basic causes and mechanisms of rollover accidents to studies of more advanced occupant protection measures. As the phenomenon of a rollover accident is longer in duration than frontal, side or rear impacts, it is relatively difficult [1] to simulate such accidents for experimental verification and also for proper evaluation of occupant restraint system performance. In this work, we focused on the trip-over type, which occurs most frequently, and performed simulations to reproduce real-world rollover accidents by combining PC-Crash and FEA.

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.

Most of the side impact air bag systems in the current market are designed to protect the thorax area only. The new Head and Thorax SRS Side Impact Air Bag system, which Nissan recently introduced into the market, was designed to help provide additional protection for the head in certain side impacts. The system may help protect occupant head contacts when the vehicle collides into a tree, or the high hood of a large striking vehicle. This paper introduces the additional features and function of the new Head and Thorax SRS Side Impact Air Bag system, and some evaluation results in laboratory testing.

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.

A new control system for the coasting range was designed with the μ-synthesis technique to achieve robust stability, based on the slip speed control system that was reported in our previous paper.(1) The results of driving tests conducted with the fuel supply cut off while coasting confirm that the new control system is able to avoid engine stall even under sudden hard braking on a low friction road (μ<0.1) at a vehicle speed of 20 km/h and a turbine speed of 1000 rpm. The system also allows the lock-up clutch to slip stably at a certain target slip speed at anytime while coasting and achieves robust performance against characteristic variations of the lock-up mechanism. This slip speed control system thus makes it possible to extend the fuel cut-off range to a lower engine speed of 800 rpm, down from 950 rpm, thereby improving fuel economy by about 1%.

Aiming for an environmental vehicle, since the 1990s we have narrowed our focus to the development of an exclusive use lithium-ion battery, and we have strongly advanced our examinations into high-performance power supply systems. In order to adapt a battery to meet vehicle requirements, it is necessary to more accurately predict battery performance, and have the ability to design it. For example, in the applicability to HEVs(Hybrid Electric Vehicles), ensuring battery power with certainty is required, but in order to improve battery power, the basic process that occurs inside the battery was restrained, so it is possible that the quantitative analytical approach is the necessary fundamental technology.

Curbing emissions of carbon dioxide (CO₂), which is believed by many scientists to be a major contributor to global warming, is one of the top priority issues that must be addressed by automobile manufacturers. Automakers have set their own strategies to improve fuel economy and to reduce CO₂ emissions. Some of them include integrated approaches, focusing on not only improvement of vehicle technology, but also human factors (eco-driving support for drivers) and social and transportation factors (traffic management by intelligent transportation systems [ITS]). Among them, electric vehicles (EVs) will be a key contributor to attaining the challenging goal of CO₂ reduction. Mass deployment of EVs is required to achieve a zero-emission society. To accomplish that, new advanced technologies, new business schemes, and new partnerships are required.

Lock-up operation of an automatic transmission is known as one good method of improving fuel economy. However, locking up the transmission at low vehicle speeds can often cause undesirable vibration or booming noise. Slip control of the lock-up clutch can resolve these problems, but the speed difference of the lock-up clutch needs to be controlled at a certain value. This control system has to overcome large changes in the parameters of the lock-up system at low vehicle speeds and also changes with regard to the speed ratio in a continuously variable transmission (CVT). In this study, this complex non-linear system has been modeled as a first-order linear parameter varying (LPV) system. A robust control algorithm was applied taking various disturbances into account to design a new slip lock-up control system.

Every fuel injection system for DI gasoline engines has a DC-DC converter to provide high, stabile voltage for opening the injector valve more quickly. A current control circuit for holding the valve open is also needed, as well as a large-capacity capacitor for pilot injection. Since these components occupy considerable space, an injector drive unit separate from the ECU must be used. Thus, there has been a need for a fuel injection system that can inject a small volume of fuel without requiring high voltage. To meet that need, we have developed a dual coil injector and an opening coil current control system. An investigation was also made of all the factors related to the dynamic range of the injector, including static flow rate, fuel pressure, battery voltage and harness resistance. Both efforts have led to the adoption of a battery voltage-driven fuel injector.

The numerical relations between occupant restraint systems and injury indexes were investigated by multi-parameter optimization of an integrated restraint system model of frontal crash simulations. This paper proposes a method of optimizing restraint systems in two types of test configurations: a 35-mph full overlap crash model and a 40-mph 40%-offset crash model.

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.

Eight rollover research tests were conducted using the 2001 Nissan Pathfinder with a modified FMVSS 208 dolly rollover test method where the driver and right front dummy restraint performance was analyzed. The rollover tests were initiated with the vehicle horizontal, not at a roll angle. After the vehicle translated laterally for a short distance, a trip mechanism was introduced to overturn the vehicle. Retractor, buckle, and latch plate performance in addition to the overall seat belt performance was analyzed and evaluated in the rollover test series. Retractor pretensioners were activated near the rollover trip in three of the tests to provide research data on its effects. Various dummy sizes were utilized. The test series experienced incomplete data collection and a portion of the analog data was not obtained. National Automotive Sampling System (NASS) data was also analyzed to quantify the characteristics of real world rollovers and demonstrated the benefits of restraint use.

The influence on vehicle dynamics of braking force distribution to four wheels has been analyzed by computer simulation and experimentation. The analytical results indicate that a suitable braking force distribution control method can improve handling and stability during braking. A new braking force distribution cintrol strategy,using a steering wheel angle feedforward function and a yaw velocity feedback function,is shown to improve vehicle dynamic behavior.

The growing number of electronic components used in automobiles lately has given rise to problems concerning the increasing number, size and weight of the wiring harnesses. As one approach to resolving these problems, the authors proposed a multiplex method based on the direction of signal flow in 1988 (SAE880589). However, the need to reduce the number of wiring harnesses circuits further made it necessary to develop a more sophisticated system. This paper presents an on-board Class A local area network (LAN) system that overcomes the problems in conventional multiplexing systems through the use of a master-slave configuration, a polling selection method and a system that integrates of electronic circuits with switch modules.

Recent environmental concerns such as atmospheric pollution and energy conservation have intensified the need to develop pollution-free, energy-efficient vehicles. One such solution is the electric automobile which draws its power from rechargeable batteries. There are few vehicles on the road today because present batteries can store very little energy compared with that of a tank of gasoline. To obtain adequate range, this concept vehicle adopts a new battery which can be recharged to 40% of capacity in six minutes. This super quick charging system makes it possible to recharge the batteries at an electric recharging station just as gasoline-powered vehicles are refilled at service stations. The electric concept vehicle also has improved aerodynamics, reduced rolling resistance and a lighter curb weight, which help to assure adequate range.