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Recent engine systems have become complex due to the requirements of fuel efficiency, exhaust gas emission control and good drivability. To decrease engine development period, model-based development has been adopted [1]. For torque-based vehicle control, engine torque estimation models are necessary. Simple mean-value torque models are available but these models require large amount of test data for development and validation. In addition, they cannot estimate transient torque precisely. On the other hand, complex physical models require considerable time for modeling and simulation. In order to decrease modeling time and retain model accuracy, the Wiebe function is utilized to calculate the heat release rate.

This paper demonstrates the development of a full multi-body vehicle model and its use in virtual design and troubleshooting of a vehicle response to throttle input. The multibody model is divided into three main subsystems: the chassis, the driveline and the powertrain subsystems. The chassis system includes a complete representation of both the front and the rear suspensions, both the front and rear subframes, and the vehicle body. The driveline system includes the output shafts from the transmission unit to the tires. The powertrain system includes complete representation of the cranktrain for a V6 combustion engine. Also included in the powertrain is a nonlinear representation of the gearbox where bearing clearances and gear lashes are considered. The cranktrain torque output is linked to the transmission using a torque converter model. The vehicle components are virtually assembled together through different joint types, force elements, and kinematic constraints.

This paper describes development of a numerical simulation method for the FMVSS 201 testing. This method considers not only deformation but also fracture of plastic materials. a simplified calculation method for predicting the load during impact of absorbing plastic materials was introduced from the numerical simulation results. By applying this simplified calculator method trial and error in development would be reduced.

Toyota Motor Corporation has already designed and developed vehicle brake control systems for relatively low speed off-road driving, such as Downhill Assist Control, Hill-start Assist Control and Active Traction Control. Though off-road utility is improved by virtue of these systems, in specific situations actual performance still depends on driving technique since the driver is required to control the accelerator pedal. Toyota has integrated these existing systems, and developed a new driving technology for off-road driving called “Crawl Control.” Crawl Control automatically modulates brake torque and drive torque to help keep the vehicle speed constant and slow. Unskilled drivers can thereby attain improved capabilities in places where high-level driving techniques are required. This system also reduces the effort required to control the accelerator and the brake pedal. This paper presents a new control algorithm for the realization of this Crawl Control system.

To meet the market requirement for headlamps having lower power consumption, high photometric performance and long life whilst providing new styling opportunities, it has been anticipated that LED light sources would provide the necessary technological basis. Against this backdrop, Koito has succeeded in developing the necessary headlamp technologies and commercializing the world's first headlamp utilizing white LED's. The key point is that the various challenges associated with the development of an LED headlamp such as the commercial application of a synthesized light distribution, control of the light axis structure for the multi-lamp system, development of adequate thermal management for the cooling of the LED's and the achievement of volume production of the lamps have been successfully overcome.

NO2 sources of roadside atmosphere at Matsubarabashi monitoring station in Tokyo were investigated analytically. The result showed that contribution of urban background is dominant from November to February and NO oxidation with O3 has large contribution from April to September. NO2 air quality standard will be achieved by reducing vehicle NOx emission to post-new long-term regulation level. The analytical method was verified by using our developed simulation system, which consists of micro traffic flow analyzer and CFD-based, unsteady-state diffusion with chemical reaction solver.

Stringent emission regulations call for advanced catalyst substrates with thinner walls and higher cell density. However, substrates with higher cell density increase backpressure, thinner cell wall substrates have lower mechanical characteristics. Therefore we will focus on cell configurations that will show a positive effect on backpressure and emission performance. We found that hexagonal cells have a greater effect on emission and backpressure performance versus square or round cell configurations. This paper will describe in detail the advantage of hexagonal cell configuration versus round or square configurations with respect to the following features: 1 High Oxygen Storage Capacity (OSC) performance due to uniformity of the catalyst coating layer 2 Low backpressure due to the large hydraulic diameter of the catalyst cell 3 Quick light off characteristics due to efficient heat transfer and low thermal mass

Through a polymer design and precise morphology control, The Super Olefin Polymer, TSOP-1 and TSOP-5 were developed for the material consolidation of interior and exterior parts, respectively. Due to a good balance of TSOP performance, several conventional materials were consolidated into one material for each application. Accordingly, considerable amounts of weight reduction and cost savings have been obtained. In addition to the excellent recyclability of TSOP, the coated bumpers collected from the market were re-utilized through paint decomposition technology. The first dashboard construction, molded partially with foam-padded skin, was also realized. The current amount of TSOP used in a vehicle is about 30% of the total amount of plastic materials. Through the usage of TSOP, 70% of the material consolidation has been achieved.

The glass-integrated Curved Seal Extrusion (hereafter called “CSE”) is a new technology for manufacturing automobile-window mole. This technology is to extrude and stick mole directly on 3-D shaped window-glass by using the combination of a multi-axes robot and an extruding machine. This process could not be realized through the previous robot technology whose primary purpose was transporting goods, which did not necessitate real-time speed control. This time, we adopted a robot for the purpose of processing plasticity molding. For the purpose of improving formability, productivity, and appearance quality, we optimized the robot's movements and devised a method to vary the molding speed of the extruding machine. Furthermore, we have established a mass production technology by developing the optimum robot control method.

Merging a CAE shape optimization system and a concept Taguchi method SN-ratio index, a robustness-focused automated shape optimization method has been developed. Applying this method to diesel intake ports, with mold position tolerance set as the error factor, SN-ratio was defined for swirl stability. As a result of the optimization provided by a multi-objective genetic algorithm, simultaneous improvement of flux, swirl rotation and SN ratio was achieved.

This paper describes the development and achievement of a target engine sound for a V6 SUV in consideration of the sound quality preferences of customers in the U.S. First, a simple definition for engine sound under acceleration was found using order arrangement, frequency balance, and linearity. These elements are the product of commonly used characteristics in conventional development and can be applied simply when setting component targets. The development focused on order arrangement as the most important of these elements, and sounds with and without integer orders were selected as target candidates. Next, subjective auditory evaluations were performed in the U.S. using digitally processed sounds and an evaluation panel comprising roughly 40 subjects. The target sound was determined after classifying the results of this evaluation using cluster analysis.

The use of lead-free (Pb-free) solder and plating in onboard electronic components has accelerated rapidly in recent years, but solutions have yet to be found for the issues of whisker generation in tin (Sn) plating and crack initiation in Pb-free solder, despite widespread research efforts. Analysis of the whisker generation mechanism has focused on internal energy levels and crystal orientation, and analysis of the crack initiation mechanism in Pb-free solder has examined changes in the grain boundaries of Sn crystals.

Breath alcohol interlock systems are used in Europe and the U.S. for drunk driving offenders, and a certain effect has been revealed in the prevention of drunk driving. Nevertheless, problems remain to be solved with commercialized detectors, i.e., a person taking the breath alcohol test must strongly expire to the alcohol detector through a mouthpiece for every test, more over the determination of the breath alcohol concentration requires more than 5 seconds. The goal of this research is to develop a device that functions suitable and unobtrusive enough as the interlock system. For this purpose, a new alcohol detector, which does not require a long and hard blowing to the detector through a mouthpiece, has been investigated. In this paper, as a tool available on board, a contact free alcohol detector for the prevention of drunk driving has been developed.

Temperature stratification plays an important role in HCCI combustion. The onsets of auto-ignition and combustion duration are sensitive to the temperature field in the engine cylinder. Numerical simulations of HCCI engine combustion are affected by the use of wall boundary conditions, especially the temperature condition at the cylinder and piston walls. This paper reports on numerical studies and experiments of the temperature field in an optical experimental engine in motored run conditions aiming at improved understanding of the evolution of temperature stratification in the cylinder. The simulations were based on Large-Eddy-Simulation approach which resolves the unsteady energetic large eddy and large scale swirl and tumble structures. Two dimensional temperature experiments were carried out using laser induced phosphorescence with thermographic phosphors seeded to the gas in the cylinder.

Mass reduction of parts is growing in importance as a means for reducing CO2 emissions from vehicles.The aim of the present research was to contribute to further mass reduction of pistons by developing a new aluminum casting material with highest level of fatigue strength. This goal was achieved using a development concept of creating a homogeneous structure in which Ti was added to create a fine structure and appropriate quantities of Fe and Mn were added to form a compound that is stable at high temperatures. Stand-alone tests of prototype pistons fabricated using the developed material show that the material is 14% stronger than the conventional material, thereby enabling increases in power and mass reduction.

A method for predicting body deformation during operation, which cannot be measured by conventional methods, has been developed. The method creates a body model based on the characteristics extracted by modal analysis of the results of a vibration testing of an actual vehicle. The model is combined with a suspension model, using multibody dynamics software, and body deformation calculations are performed. In this paper, the influence of body deformation on vehicle controllability and stability is studied and the usefulness of the method is verified.

In this paper, the dynamic movement of a driveshaft with imbalance is calculated from the bending stress of a driveshaft at a vehicle test. The synthesis movement is simulated using vertical and horizontal bending models with the centrifugal force induced by the imbalance. Thus, the mechanism that bending stress arises at a driveshaft of a general power train is clarified. The analysis using the simulation shows the relationship between vertical and horizontal stiffness of a power train and dynamic movement of a driveshaft. As a result, a method to reduce bending stress of a driveshaft is proposed.

Introduction of occupant classification system which has load sensor with a strain gauge built into the seat structure, and identifies occupant's physique by measuring weight on seat, and meets the United States FMVSS requirements (new FMVSS208 Requirement).

Recently, the development of advanced automotive technology for excellent safety and convenience has become more active. Efforts have focused on the development of active safety technology. Pre-Crash Systems, such as passenger protection systems activated before a collision or collision speed reduction system, which are categorized between active safety systems and passive safety systems, have been a subject of focus. In such systems, surround sensing technology to predict a collision is the key issue. We developed an electronically scanning millimeter-wave (MMW) RADAR, which uses Digital Beam Forming (DBF) technology, as one of the first in the world for automotive applications.

We developed a progressive system, “virtual and real simulator (V&R-S)” for engine. To innovate the process of engine development, the test system creates dynamic load of drivetrain, wheel, body and road with the virtual vehicle model. We set the phenomena such as drivetrain vibration for reproducing object of this system. The load is transmitted to the engine crankshaft end as torque with the connecting shaft made of fiberglass. The mainly developed technologies are the dynamometer with rotational inertia as low as engine, correction method of transmitted torque error of connecting shaft by H-infinity control. Thanks to these, we achieved the capability of optimization for most of dynamic characteristics (emission, fuel consumption, drivability) on engine test bench. And we now be able to limit real vehicle test to the final tuning. As a result, we have realized new engine evaluation and optimization process.