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In this paper, we consider smart charging and vehicle-to-home (V2H) technologies for plugin electric vehicles coordinated with home energy management systems (HEMS) for automated demand response. In this system, plugin electric vehicles automatically react to demand response events with or without HEMS’s coordination, while vehicles are charged and discharged (i.e., V2H) in appropriate time slots by taking into account demand response events, time-ofuse rate information, and users’ vehicle usage plan. We introduce three approaches on home energy management: centralized energy control, distributed energy control, and coordinated energy control. We implemented smart charging and V2H systems by employing two sets of standardized communication protocols: one using OpenADR 2.0b, SEP 2.0, and SAE standards and the other using OpenADR 2.0b, ECHONET Lite, and ISO/IEC 15118.

This paper presents a modeling method for prediction of low-frequency road noise in a steady-state condition where rotating tires are excited by actual road profile undulation input. The proposed finite element (FE) tire model contains not only additional geometric stiffness related to inflation pressure and axle load but also Coriolis force and centrifugal force effects caused by tire rotation for precise road noise simulation. Road inputs act on the nodes of each rib in the contact patch of the stationary tire model and move along them at the driving velocity. The nodes are enforced to displace in frequency domain based on the measured road profile. Tire model accuracy was confirmed by the spindle forces on the rotating chassis drum up to 100Hz where Coriolis force effect should be considered. Full vehicle simulation results showed good agreement with the vibration measurement of front/rear suspension at two driving velocities.

This paper proposes a novel method of verifying comprehensive driver model used for the evaluation of driving safety systems, which is achieved by coupling the traffic simulation and the driving simulator (DS). The method consists of three-step procedure. In the first step, an actual driver operates a DS vehicle in the traffic flow controlled by the traffic simulation. Then in the next step, the actual driver is replaced by a driver model and the surrounding vehicle maneuvers are replayed using the recorded data from the first step. Then, the maneuver by the driver model is compared directly with the actual driver's maneuver along the simulation time steps.

The application of Model-Based Development (MBD) techniques for automotive control system and software development have become standard processes due to the potential for reduced development time and improved specification quality. In order to improve development productivity even further, it is imperative to introduce a systematic Verification and Validation (V&V) process to further minimize development time and human resources while ensuring control specification quality when developing large complex systems. Traditional methods for validating control specifications have been limited by control specification scale, structure and complexity as well as computational limitations restricting their application within a systematic model-based V&V process. In order to address these issues, Toyota developed Hierarchical Accumulative Validation (HAV) for systematically validating functionally structured executable control specifications.

A number of active safety systems are already developed to support drivers’ decision and action to help avoid accidents, but further enhancement of those active safety systems cannot be accomplished without increasing our understanding on driver behaviors and their interaction with vehicle systems. For this reason, a state-of-art driving simulator (DS) has been developed that creates very realistic scenarios as a means of realizing these requirements. The DS consists of a simulator cabin, turntable (inside the dome), a 6-DOF hexapod system, shakers (vehicle vertical vibration actuators), and a motion system capable of moving 35 meters longitudinally and 20 meters laterally. The system is also capable of projecting images of actual city streets and highways onto a 360° spherical screen inside of the dome. As a result, the DS is able to reproduce a driving environment that is very similar to real driving.

With the support of Horiba and Horiba STEC, Toyota Motor Corporation has developed an exhaust emissions simulator to verify the accuracy of extremely low emissions measurement systems. It can reliably verify the accuracy (correlation) of each SULEV emission measurement system to within 5% under actual conditions. The simulator's method of simulating SULEV gasoline engine cold-start emissions is to inject bottled gases with known concentrations of each emission constituent to the base gas, which is clean exhaust gas from a SULEV vehicle with new fully warmed catalysts. First, the frequencies and dynamic ranges of the SULEV cold-start emissions were analyzed and the method of 2 injecting the bottled gases was considered based on the results of that analysis. A high level of repeatability and accuracy was attained for all injection flow ranges in the SULEV cold-start emission simulation by switching between high-response digital Mass Flow Controllers (MFCs) of different full scales.

This paper describes that a method has been developed to estimate the range of the scatter of Head Injury Criterion (HIC) values in pedestrian impact tests, which could help to reduce the range of the scatter of HIC values by applying the stochastic method for Finite Element (FE) analysis. A major advantage of this method is that it enables the range of scatter of HIC values to be estimated and to explain the mechanics of the behavior. The test procedure of pedestrian impact allows some tolerances for the resultant conditions of impact such that the distance of actual impact location from the selected point is within 10 mm and the impact velocity is within ±0.7 km/h [1]. A HIC value calculated by impact simulation under a deterministic impact condition with the nominal input data does not necessarily represent the variation of measured data in impactor tests.

Compatibility in vehicles crashes has been studied worldwide in recent years. In cases where primary energy-absorbing structures such as front end members were bypassed in front-to-front collisions, energy-absorbing efficiency declined compared to cases when no such bypassing occurred. A bumper beam that connects the front end members in the transverse direction can help prevent bypassing of primary energy-absorbing structures. The strength balance between front end members and a bumper beam was studied in this paper. It was verified in front-to-front offset vehicle collision tests that crash energy can be efficiently absorbed by balancing the strength of the bumper beam with the compression strength of the front end members.

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.

We have developed a novel engine cycle simulation program (UniDES: universal diesel engine simulator) to reproduce the diesel combustion process over a wide range of engine operating parameters, such as the amount of injected fuel, the injection timing, and the EGR ratio. The approach described in this paper employs a zoning model, where the in-cylinder region is divided into up to five zones. We also applied a probability density function (PDF) concept to each zone to consider the effect of spatial non-homogeneities, such as local equivalence ratios and temperature, on the combustion characteristics. We linked this program to the commonly used commercial GT-Power® software (UniDES+GT). As a result, we were able to reproduce transient engine behavior very accurately.

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.

Due to the relative high speed and short distance between the door and occupant, side impact presents a challenging task when analyzing the input force from the door to the occupant. The new FMVSS214 Final Rule in 2007 and the new NCAP in 2008 mandated the use of a SID-IIs in the oblique pole impact test and in the rear seat during an MDB side impact test. Therefore, a high-precision measurement and calculation of the three-dimensional dummy kinematics, as well as the interaction of force inside the dummy (internal force) and force exerted from outside the dummy (external force) will help provide efficient evaluation of design requirements for the door trim and supplemental restraint systems that meet legally mandated requirements.

In this study, we evaluated subjective nighttime discomfort-glare responds on three different types of planar and non-planar driver-side mirrors on two age groups. Fifty-six individuals (28 young [18-35 years] and 28 old [65 years and over]) participated in this experiment. Subjective discomfort-glare rating scores on three different types of driver-side mirrors were assessed utilizing De Boer's rating scale in a controlled nighttime driving environment (laboratory ambient illuminant level - l lux with headlight turned off). Three driver-side mirrors included: planar (“flat mirror” - reflectance ratio of 39.12%) and nonplanar (“curved mirror” - reflectance ratio of 8.78% and “blue mirror” - reflectance ratio of 7.77%; R=1400mm). The results indicated that with the same glare level (as measured by angle of incidence and illuminance on the front of the eyes), older adults reported lower De Boer's rating scores (i.e. worse feelings of glare) than their younger counterparts.

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.

The experimental research vehicle ES3 body was realized by using various aluminum-joining technologies: MIG welding, laser welding, self-piercing riveting. These technologies were applied selectively to make full use of their individual characteristics, according to the body structure and joined materials. Of these technologies, self-piercing riveting is advantageous in several respects. Aiming to expand the application range of riveting technology, we developed a die that prevents cracks in joining aluminum casting, and a method to improve rivet driving in thick, multi-pile portion. We further studied the feasibility of aluminum rivets. This paper outlines the ES3 body structure and it's joining technologies used and introduces the further improvements we developed concerning self-piercing riveting.

In the initial design stage, it is important to discuss what kind of body concept is effective from a viewpoint of environment burden reduction. This paper describes the importance of both weight reduction and recycling through conducting LCA (Life Cycle Assessment) for four kinds of body structures. In addition, using each software, DFMA (Design for Manufacture and Assembly), DFE (Design for Environment) and LCA to parts unit, each effectiveness was discussed through the assessment of the material-hybrid body.

In FOA (First Order Analysis) any vehicle body structure might be interpreted as a collective simple structure that can be decomposed into 3 fundamental structure types. The first structure is the “BEAM”, whose cross sectional properties as well as its material dominates the mechanical behavior, the second is the “PANEL (shear panel, plate, and shell)”, whose mechanical behavior can be varied by changing its geometrical properties in the thickness direction, i.e. adding beads or flanges. The third structure is the “JOINT”, which connects the proceeding structures, and transfer complex three-dimensional loads with three-dimensional deformation. In the present work, we shall propose a methodology to identify a portion of an arbitrary FE model of an automotive body structure, with a “BEAM” structure in the FOA approach. In the latter chapter of this paper, cross section loads will be related with cross sectional properties in the aspect of the element strain energy concept.

Underbody coating is used to prevent chipping damage of the automobile underbody and wheel well. Multi-functional material that gives sound insulating properties is called sound insulating underbody coating. This paper describes the development of underbody coating material with powdered acrylic composition as an alternative to polyvinyl chloride resin. The new material also has better foaming properties. It is possible to ensure excellent sound insulating performance with thin film. This multi-functional underbody coating is the first application in the world with weight reduction and cost saving, and in a more environmentally acceptable manner.

The use of a head-up display (HUD) system has become popular recently, as it can provide feedback information at a position easily seen by the driver. However, the outline of the HUD bezel often reflects on the windshield of a HUD equipped vehicle. This phenomenon occurs when the sun is at a high position and reflects off the top of the instrument panel and the front view is dark. For this reason, it can occur when driving on asphalt paved roads, causing annoyance to the driver. Under fixed environmental conditions, the vehicle based factors that influence the annoyance caused by reflected boundary lines are the position of the reflection, line thickness, and the contrast of the reflected boundary line. These can be represented by the conspicuity of a striped pattern (contrast sensitivity function). In previous research in 1991, M. S. Banks et al. studied a contrast sensitivity function that included the factors stated above.

The tendency for car engines to reduce the cylinder number and increase the specific torque at low rpm has led to significantly higher levels of low frequency pulsation from the exhaust tailpipe. This is a challenge for exhaust system design, and equally for body design and vehicle integration. The low frequency panel noise contributions were identified using pressure transmissibility and operational sound pressure on the exterior. For this the body was divided into patches. For all patches the pressure transmissibility across the body panels into the interior was measured as well as the sound field over the entire surface of the vehicle body. The panel contributions, the pressure distribution and transmissibility distribution information were combined with acoustic modal analysis in the cabin, providing a better understanding of the airborne transfer.