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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

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.

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.

This study examined methods of machining a microsurface texture on the surface of the rolling elements of a toroidal continuously variable transmission (CVT) for improving the traction coefficient. The microsurface texture of the toroidal surfaces consists of tiny circumferential grooves (referred to here as micro grooves) and a mirror-like surface finish similar to the rolling surface of bearings. Hard turning with a cubic boron nitride (cBN) cutting tool, grinding with a cBN wheel and micro forming were applied to machine the micro grooves. The results made clear the practical potential of each method. A micro forming device was also developed for use in actual production. A mirror-like surface finish and micro crowning of the convex portions of the microsurface texture were simultaneously executed by superfinishing them with a fine-grained elastic superfinishing stone.

This paper quantifies the potential of electric propulsion systems to reduce petroleum use and greenhouse gas (GHG) emissions in the 2030 U.S. light-duty vehicle fleet. The propulsion systems under consideration include gasoline hybrid-electric vehicles (HEVs), plug-in hybrid vehicles (PHEVs), fuel-cell hybrid vehicles (FCVs), and battery-electric vehicles (BEVs). The performance and cost of key enabling technologies were extrapolated over a 25-30 year time horizon. These results were integrated with software simulations to model vehicle performance and tank-to-wheel energy consumption. Well-to-wheel energy and GHG emissions of future vehicle technologies were estimated by integrating the vehicle technology evaluation with assessments of different fuel pathways. The results show that, if vehicle size and performance remain constant at present-day levels, these electric propulsion systems can reduce or eliminate the transport sector's reliance on petroleum.

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.

This paper proposes a method of estimating road friction and tire slip angle in a cornering maneuver. The method can estimate front tire road friction accurately at low lateral acceleration because it is based on the tire self-aligning torque (SAT) that exhibits high sensitivity to road friction at low slip angles. Road friction and tire slip angle, which are mutually interdependent, are estimated simultaneously using an extended Kalman filter designed around a model describing the relationship between road friction and SAT and a vehicle lateral dynamic model. The front tire SAT is calculated with a mathematical model that describes the torque transmission characteristics from the electric power steering torque to SAT. Therefore, the proposed method is readily applicable to production vehicles. Results of an experimental study show that the change in road friction is instantaneously estimated at low lateral acceleration.

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.

A block-on-ring friction and wear testing machine (LFW-1) was used as a test method for making fundamental evaluations of the effect of the Belt-Drive Continuously Variable Transmission(B-CVT) fluid on the friction coefficient between the belt and pulleys. The results confirmed that this method can simulate the friction phenomena between the belt and pulleys of an actual transmission. The mechanism whereby ZDDP and some Ca detergents improve the torque capacity of a B-CVT was also investigated along with the effect of the deterioration of these additives on the friction coefficient. It was found that these additives form a film, 80-90 nm in thickness, on the sliding surface, which is effective in increasing the friction coefficient. The friction coefficient declined with increasing additive deterioration. The results of a 31P-NMR analysis indicated that the decline closely correlated with the amount of ZDDP in the B-CVT fluid.

“Do not let an accident happen” - SUBARU believes this is the ultimate safety measure and has been actively working on the establishment of active safety technology such as the commercialization of an autonomous driving support system. The advancement of the technology needs the development of the interface between the driver and vehicle (human-machine interface). This study examined whether intonated voice can be applied to warning. The results indicated the effectiveness of intonated voice as a means of providing auditory information and warning to drivers.

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.

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.

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.

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.

The life of automotive transmission gears today is often governed by pitting fatigue life. Being able to predict pitting fatigue life accurately is a crucial issue. Pitting fatigue life is substantially influenced by surface hardness and tooth surface geometry. For that reason, this study examined a new method of predicting pitting fatigue life that takes into account changes in these factors over time. This method makes it possible to predict the pitting fatigue life of automotive transmission gears under a wide range of evaluation conditions with markedly better accuracy than conventional methods used previously.

This paper assesses the potential improvement of automotive powertrain technologies 25 years into the future. The powertrain types assessed include naturally-aspirated gasoline engines, turbocharged gasoline engines, diesel engines, gasoline-electric hybrids, and various advanced transmissions. Advancements in aerodynamics, vehicle weight reduction and tire rolling friction are also taken into account. The objective of the comparison is the potential of anticipated improvements in these powertrain technologies for reducing petroleum consumption and greenhouse gas emissions at the same level of performance as current vehicles in the U.S.A. The fuel consumption and performance of future vehicles was estimated using a combination of scaling laws and detailed vehicle simulations. The results indicate that there is significant potential for reduction of fuel consumption for all the powertrains examined.

The durability test with road-load input is necessary for evaluating durability of body and chassis structure in automotive applications. This paper shows the method to analyze road-load input to a suspension system for development of a simple component level bench test. This method enables the extraction of the essential inputs to evaluate the durability of suspension parts using the transfer function (frequency response function) measured by Multi-axial Road Simulator and wheel force transducers. These extracted inputs contribute to development of a new realistic component bench test.

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%.

Building a toroidal continuously variable transmission (CVT) with multiple power rollers arranged in parallel is an effective way to improve its torque capacity. However, that requires a method for synchronizing the operation of all of the power rollers. This paper describes a method of synchronizing the four power rollers in a toroidal CVT that we have researched and developed. It also presents the results of an analysis of the cause of power roller vibration, which was a serious issue encountered in the development process, and describes an effective method for preventing it. The methods described here achieve sufficient synchronization performance for practical use of the toroidal CVT on production vehicles.