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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

This paper proposes a rolling machine that forms fine corrugated section patterns for thin sheets. A prototype of the machine was made and the performance of the machine was tested. As compared with press forming, rolling has the advantages of the high forming limit, the low forming reaction force, the easy control of the thin sheet's curve and high productivity. We confirmed these four advantages by using finite element analyses and the prototype rolling machine. Stainless steel sheets and titanium sheets, which were one of the materials with a low forming limit, were used. Firstly, the rolling showed a 1.3-times higher forming limit than the press forming in the case that a fine corrugated section pattern was formed in a stainless steel sheet of 22-mm square sizes. Secondly, the forming reaction force of the rolling was about one-twentieth of the press forming without coining, and the experimental results agreed with the finite element simulation.

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.

This study concerns a dissimilar materials joining technique for aluminum (Al) alloys and steel for the purpose of reducing the vehicle body weight. The tough oxide layer on the Al alloy surface and the ability to control the Fe-Al intermetallic compound (IMC) thickness are issues that have so far complicated the joining of Al alloys and steel. Removing the oxide layer has required a high heat input, resulting in the formation of a thick Fe-Al IMC layer at the joint interface, making it impossible to obtain satisfactory joint strength. To avoid that problem, we propose a unique joining concept that removes the oxide layer at low temperature by using the eutectic reaction between Al in the Al alloy and zinc (Zn) in the coating on galvanized steel (GI) and galvannealed steel (GA). This makes it possible to form a thin, uniform Fe-Al IMC layer at the joint interface. Welded joints of dissimilar materials require anticorrosion performance against electrochemical corrosion.

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.

The thermal fatigue resistance of engine exhaust system parts has conventionally been evaluated in thermal fatigue tests conducted with a restrained specimen. However, the test results have not always been consistent with data obtained in engine endurance tests. Two new evaluation methods have been developed to overcome this problem. One is a method of predicting thermal fatigue life on the basis of nonlinear elastic and plastic thermal analyses performed with a finite element model and the ABAQUS program. The other is a method of evaluating exhaust system parts using an exhaust system simulator. This paper describes the concepts underlying the two methods and their relative advantages.

This study focused on European NCAP activities of introducing a new head protection evaluation procedure, as proposed by BASt (Federal Highway Research Institute - GERMANY). Various kinds of E-bikes are available in the market, ranging from E-bikes that have a small motor to assist the rider’s pedal-power i.e., pedelecs to somewhat more powerful E-bikes which is similar to a moped-style scooter. This paper focused on identifying the factors influencing bicyclist head kinematics during bicycle vs. passenger vehicle (PV) collisions at the intersection. Two AM50 bicyclist FE models are developed using i) GHBMC Human Body Model (HBM) and ii) WorldSID (WS) side impact dummy. Head kinematics of bicyclists of pedal-assist E-bike and normal bike were compared using CAE simulation. It is found that the vehicle’s impact velocity, type of bicycle, the mass of E-bike and bicycle traveling speed will influence the head kinematics.

The demands on valve seat insert materials, in terms of providing greater wear-resistance at higher temperatures, enhanced machinability and using non-environmentally hazardous materials at a reasonably low cost have intensified in recent years. Due therefore to these strong demands in the market, research was made into the possibility of producing a new valve seat insert material. As a result a high speed steel based new improved material was developed, which satisfies the necessary required demands and the evaluation trials, using actual gasoline engine endurance tests, were found to be very successful.

This paper describes the relationship between the design parameters used to define the geometry of an automotive torque converter and the resultant efficiency in relation to the internal flow characteristics. Taking the turbine bias angle and the contraction ratio of the pump flow passage as specific examples, the effects of each design parameter on the internal flow characteristics and the occurrence of loss were analyzed. A three-dimensional viscous flow analysis code was used in the numerical computation procedure and a method developed independently by the authors was used in the loss analysis. The flow near the wall was visualized experimentally using a technique resembling the so-called oil film method. The visualized results showed good qualitative agreement with the numerical analysis results.

Many studies have been reported concerning fundamental tribological research aimed at reducing the severe valve train wear that occurs in internal combustion engines. In this paper, cam follower wear was theoretically and experimentally analyzed at the material development stage. Statistical methods have been applied to practical use in determining the material properties quantitatively. Based on the results, a method for predicting cam follower wear has been derived which has made it possible to develop new valve train systems more efficiently. Further, a guideline for developing new wear resistant materials was also clarified. Finally, the precision high chrominum cast iron rocker arm is described, along with its application to a new NISSAN high-performance 4-cylinder DOHC engine, as an example of the use of this method to develop new wear-resistant materials.

A flatter design is becoming increasingly important for reducing torque converter axial size and weight. The conventional stator design method, in which the blade profile is geometrically determined and flow analysis of the profile may give some valuable information, is no longer sufficient for achieving efficient flow turning in the short axial length of flat torque converters. Here, after a brief review of the conventional design approach, an inverse design method is introduced, which yields a blade profile solution for a prescribed favorable velocity distribution along the blade. The performance improvement with this procedure has been demonstrated experimentally.

Application of microalloyed steel to automobile parts is becoming increasingly common in Japan. However, fatigue properties of actual automotive forged parts with slight notches on their surface have not been fully clarified. In this work, the fatigue properties of microalloyed steel were studied using test specimens and also actual automotive parts. The results indicated that microalloyed steel with an optimal microstructure showed higher notch fatigue resistance than quenched-tempered steel. The improvement of material technology and the application of microalloyed steel have not only served to bring product costs down, but have paved the way for part weight reductions. Lightweight connecting rods for the newly developed Nissan engines have been produced, contributing to improved engine performance.

An electronically controlled five-speed automatic transmission has been developed for use in new 2-liter models. This high-performance gearbox is the world's first five-speed automatic transmission for passenger car use to be equipped with a torque converter. It is designed with an ultra-wide range and close ratio gearing and incorporates a host of outstanding technologies to provide excellent performance and driveability. This paper describes the major features and performance of this new automatic transmission and some of the studies undertaken concerning multiplication of gear steps.

In Europe and the U.S., fracture split connecting rods are used in many types of current engines. This process can eliminate the machining of crankshaft end and eliminate the dowel pin for positioning. The most important key for fracture split connecting rods is a reduction in the plastic deformation during the fracture splitting process. For this reason, sinter-forged materials and pearlitic steels (C70S6) are used for fracture split connecting rods because of their low ductility. Such types of steel, however, are inferior to the hot forged microalloyed steels typically used as connecting rod material in Japan in terms of buckling strength and machinability although they are easier to fracture split. On the other hand, the conventional microalloyed steels used for connecting rods in Japan are not suitable for fracture splitting. The reason is that these steels have too much ductility and associated plastic deformation for fracture splitting.

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.

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%.

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.

The probability or risk of traffic accidents must be estimated quantitatively in order to implement effective traffic safety measures. In this study, various statistical data and probability theory were used to examine a method for predicting the risk of crossing-collisions, representing a typical type of accident at intersections in Japan. Crossing-collisions are caused by a variety of factors, including the road geometry and traffic environment at intersections and the awareness and intentions of the drivers of the striking and struck vehicles. Bayes' theorem was applied to find the accident probability of each factor separately. Specifically, the probability of various factors being present at the time of a crossing-collision was estimated on the basis of traffic accident data and observation survey data.

This paper describes a newly developed steel composition and surface modification methods for improving the rolling contact fatigue strength of parts used in transmission systems, especially continuously variable transmissions (CVTs) to increase their torque capacity. The mechanisms of two types of typical rolling contact fatigue phenomenon in case hardening steel were examined with the aim of improving rolling contact fatigue strength. One concerned white etching constituents (WEC) and the other one concerned peculiar microstructural changes caused by hydrogen originating from decomposition of the lubrication oil as a result of repeated rolling contact stress cycles. The rolling contact fatigue strength limit due to WEC has been improved markedly by dispersing fine M23C6 alloy carbides in the martensite matrix at the subsurface layer of parts.