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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

A compact and high performance electric motor, called the 3D motor and designed to achieve output torque density of 100 Nm/L, was developed for use on electric vehicles and hybrid electric vehicles. The motor adopts an axial flux configuration, consisting of a disk-shaped stator sandwiched between two disk-shaped rotors with permanent magnets. It also adopts 9-phase current with a fractional slot combination, both of which increase the torque density. The rated torque output of this high power-density motor is achieved by applying a hybrid cooling system comprising a water jacket on the outer case of the stator and oil dispersion into the air gaps. The mechanical strength of the rotors against centrifugal force and that of the stator against torque exertion were confirmed in mechanical experiments. Several measures such as flux barriers, a chamfered rotor rim, parallel windings, and radially laminated cores were adopted to suppress losses.

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.

For a numerical model of vibro-acoustic coupling analysis, such as a vehicle noise and vibration, both structural and acoustical dynamic characteristics are necessary to replicate the physical phenomenon. The accuracy of the analysis is not enough for substituting a prototype phase with a digital phase in the product development phases. One of the reasons is the difficulty of addressing the interior acoustical characteristics due to the complexity of the acoustical transfer paths, which are a duct and a small hole of trim parts in a vehicle. Those complex features affect on the nodal locations and the body coupling surface of acoustic mode shapes. In order to improve the accuracy of the analysis, the physical mechanisms of those features need to be extracted from experimental testing.

The adoption of the electronic controlled steering systems with new technologies has been extended in recent years. They have interactions with other complex vehicle subsystems and it is a hard task for the vehicle developer to find the best solution from huge number of the combination of parameter settings with track tests. In order to improve the efficiency of the steering system development, the authors had developed a steering bench test method for steering system using a Hardware-In-the-Loop Simulation (HILS). In the steering HILS system, vehicle dynamics simulation and the tie rod axial force calculation are required at the same time in the real-time simulation environment. The accuracy of the tie rod axial force calculation is one of the key factors to reproduce the vehicle driving condition. But the calculation cannot be realized by a commercial software for the vehicle dynamics simulation.

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%.

There has been a growing need in recent years to further improve vehicle fuel efficiency and reduce CO2 emissions. JATCO began mass production of a transmission for rear-wheel-drive (RWD) hybrid vehicle with Nissan in 2010, which was followed by the development of a front-wheel-drive (FWD) hybrid system (JATCO CVT8 HYBRID) for use on a midsize SUV in the U.S. market. While various types of hybrid systems have been proposed, the FWD system adopts a one-motor two-clutch parallel hybrid topology which is also used on the RWD hybrid. This high-efficiency system incorporates a clutch for decoupling the transmission of power between the engine and the motor. The hybrid system was substantially downsized from that used on the RWD vehicle in order to mount it on the FWD vehicle. This paper describes various seal technologies developed for housing the dry multi-plate clutch inside the motor, which was a key packaging technology for achieving the FWD hybrid system.

The adoption of electric vehicles (EVs) has been announced worldwide with the aim of reducing CO2 emissions. However, a significant increase in electricity demand by EVs might impact the stable operation of the existing power grid. Meanwhile, EV charging is acceptable to most users if it is completed by the time of the next driving event. From the viewpoint of power grid operators, flexibility for shifting the timing of EV charging would be advantageous, including making effective use of renewable energy. In this work, an EV model and simulation tool were developed to make clear how the total charging demand of all EVs in use will be influenced by future EV specifications (e.g., charge power) and installation of charging infrastructure. Among the most influential factors, EV charging behavior according to use cases and regional characteristics were statistically analyzed based on the real-world usage data of over 14, 000 EVs and incorporated in the simulation tool.

A new multiple dc-inputs direct electric-power converter (D-EPC) has been developed. It is placed between multiple dc power sources and an ac motor, eliminating the need for a dc/dc converter generally used in conventional converter/inverter systems. The D-PEC can improve the efficiency of the motor drive system with a more compact size. Its power distribution control is carried out by allotting voltage ratios to each of two different dc power sources on a time average basis. A new pulse-width-modulation (PWM) generation technique to drive switching devices in the D-EPC has also been developed. Tests have verified that the three-phase ac motor can be operated by controlling the power distribution between the two power sources.

In the “Nissan Green Program 2010”, released in December 2006, Nissan Motor Co., Ltd. announced plans to offer advanced technology and products to further real-world reductions in CO2 emissions. One solution is the development of a practical fuel cell vehicle (FCV). In 1996, Nissan began developing an FCV and since 2001, has participated in activities to promote the development and to educate the public on the benefits of fuel cell vehicles by participating in fleet programs in the USA (CaFCP) and in Japan (JHFC). In 2006, limited leasing of the newly-developed 2005 X-TRAIL FCV was initiated in Japan, in the Kanagawa Prefecture and in Yokohama City. In 2007, Nissan provided an X-TRAIL FCV to Kanagawa Toshi Kotsu Ltd., for use as the world's first-ever fuel cell taxi in use on pubric roads. The 2005 X-TRAIL is equipped with various newly-developed technologies, including a fuel cell stack that was engineered by Nissan in-house.

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.

A robotic driver has been designed on the basis of an analysis of a human driver's action in following a given driving schedule. The self-learning algorithm enables the robot to learn the vehicle characteristics without human intervention. Based on learned relationships, the robotic driver can determine an appropriate accelerator position and execute other operations through sophisticated calculations using the future scheduled vehicle speed and vehicle characteristics data. Compensation is also provided to minimize vehicle speed error. The robotic driver can reproduce the same types of exhaust emission and fuel economy data obtained with human drivers with good repeatability. It doesn't require long preparation time. Thereby making it possible to reduce experimentation work in the vehicle development process while providing good accuracy and reliability.

Detergent additives in automotive gasoline fuel are mainly designed to reduce deposit formation on intake valves and fuel injectors, but it has been reported that some additives may contribute to CCD formation. Therefore, a standardized bench engine test method for CCDs needs to be developed in response to industry demands. Cooperative research between the Petroleum Association of Japan (PAJ) and the Japan Automobile Manufacturers Association, Inc. (JAMA), has led to the development of a 2.2L Honda engine dynamometer-based CCD test procedure to evaluate CCDs from fuel additives. Ten automobile manufacturers, nine petroleum companies and the Petroleum Energy Center joined the project, which underwent PAJ-JAMA round robin testing. This paper describes the CCD test development activities, which include the selection of an engine and the determination of the optimum test conditions and other test criteria.

Achieving a multi-cylinder engine with excellent noise/vibration character sties and low friction at the main bearings requires an optimal design not only for the crankshaft construction but also for the bearing support system of the cylinder block. To accomplish that, it is necessary to understand crankshaft system behavior and the bearing load distribution for each of the main bearings. Crankshaft system behavior has traditionally been evaluated experimentally because of the difficulty in performing calculations to predict resonance behavior over the entire engine speed range. A coupled crankshaft-block analysis method has been developed to calculate crankshaft system behavior by treating vibration and lubrication in a systematic manner. This method has the feature that the coupled behavior of the crankshaft and the cylinder block is analyzed by means of main bearing lubrication calculations. This paper presents the results obtained with this method.

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.

A prototype navigation system with cellular phone access to an information service center was constructed and evaluated. Center personnel can also operate the system remotely, in addition to providing traffic information and information for more enjoyable travel. Real-time conversation with a center operator is also possible. The system was rated positively by most of the subjects, especially the real-time voice service. This paper describes the car navigation market and cellular phone market in Japan, the system configuration, evaluation results and possible solutions to problems in the system. It also touches on the outlook for future car navigation systems and information services.

The spray formation and mixing processes in a direct-injection gasoline engine are examined by using a sophisticated air flow calculation model and an original spray model. The spray model for a spiral injector can evaluate the droplet size and spatial distribution under a wide range of parameters such as the initial cone angle, back pressure and injection pressure. This model also includes the droplet breakup process due to wall impingement. The arbitrary constants used in the spray model are derived theoretically without using any experimental data. Fuel vapor distributions just before ignition and combustion processes are analyzed for both homogeneous and stratified charge conditions.

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.

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.