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The hybrid system has the typical advantage that it can realize various types of system control, because the system has two power units, engine and motor. On the other hand, however, constraints are increasing due to the complexity of the vehicle system. Compared to the conventional HILS construction and application, there are mainly two typical characteristics or themes for HV-HILS (i.e. HILS for hybrid vehicle control development). Firstly, HV-HILS requires full vehicle simulation environment, because the plural ECU control logic is intricately intertwined. Secondly, recent HILS system needs to run with more accurate or complicated plant models which are necessary to develop more accurate vehicle control logic.

The behavior of spray injections to turbulent duct flows from a slit injector for direct-injection gasoline engines was investigated using a combination of large eddy simulation (LES) and Lagrangian discrete droplet model (DDM). As a result, diffusion of droplets in stronger turbulent flows was observed at a later stage of the injection. Moreover, we compared calculation and experimental results by generating a pseudo-particle image from the calculation result.

In this study, it is purpose to make clear the effect of cavitation phenomenon on the spray atomization. In this report, the cavitation phenomenon inside the nozzle hole was visualized and the pressure measurements along the wall of the nozzle hole were carried out by use of 25-times enlarged acrylic nozzle. For the representatives of regular gasoline, single and two-component fuels were used as a test fuel. In addition, various cavitating flow patterns same as experimental conditions were simulated by use of Barotropic model incorporated in commercial code of Star-CD scheme, and compared with experimental results.

A new method to measure in-cylinder flame propagation and mixture distribution has been developed. The distribution is derived from analyzing the temporal history of flame spectra of CH* and C2*, which are detected by a spark plug type sensor with multi-optical fibers. The validity of this method was confirmed by verifying that the measurement results corresponded with the results of high speed flame visualization and laser induced fluorescence (LIF) measurement. This method was also applied to analysis of cyclic combustion fluctuation on start-up in a direct injection spark ignition (DISI) engine, and its applicability was confirmed.

Roadway departure mitigation systems for helping to avoid and/or mitigate roadway departure collisions have been introduced by several vehicle manufactures in recent years. To support the development and performance evaluation of the roadway departure mitigation systems, a set of commonly seen roadside surrogate objects need to be developed. These objects include grass, curbs, metal guardrail, concrete divider, and traffic barrel/cones. This paper describes how to determine the representative color of these roadside surrogates. 24,762 locations with Google street view images were selected for the color determination of roadside objects. To mitigate the effect of the brightness to the color determination, the images not in good weather, not in bright daylight and under shade were manually eliminated. Then, the RGB values of the roadside objects in the remaining images were extracted.

The development of a high tech image analog cluster providing good readability is required by today's customer. To satisfy this trend, we have developed a highly unique analog cluster, which features very sharp white lit pointers with evenly illuminated white dials on a black acrylic face. These features are primarily achieved through two new lighting sources: 1. Pointers made from thin, lightweight Cold Cathode Discharge Tubes. This pointer creates very high brightness, regardless of temperature, by enclosing xenon gas in the tube, and was designed into a single side electrode structure. 2. Circular shape Cold Cathode Tube Installed Behind Each Dial Applique. This application creates very bright high quality illumination. In this session, we would like to introduce the construction and system of two new lighting sources for lexus, LS400. This technology provide improved readability.

Besides automobile instrument clusters requiring the high precision and legibility, they must also appeal to the user's fashionable sense. We have been proud of introducing such the cluster, named New Electronic Analogue Meter for the LEXUS LS 400 high quality luxury sedan. This paper describes design features of it as the followings; (1) The acrylic lens with black out effect. (2) Utilizing the cold cathode discharge tubes for pointer and back light of dial applique. (3) The virtual image warning indicators producted on the dial applique of the speedometer or tachometer.

In this paper, the authors have developed a new measuring method of the liquid fuel film thickness on walls, such as intake ports, the combustion chamber and cylinder liner of a Port Fuel Injection (PFI) engine, and clarified the fuel film behavior under various running conditions when Fiber-based Laser-Induced Fluorescence (Fiber-based LIF) was applied to the newly developed method. The thickness of the fuel film is measured by detecting the intensity of fluorescence from the film that is irradiated by a He-Cd laser. A single optical fiber is used to simultaneously transmit the laser beam and the fluorescence from the film. In addition, the S/N ratio of the fluorescence is improved by using a He-Cd laser of which the wavelength (λ=442nm) is able to efficiently irradiate test fuel doped 2-3-butandione. Using this method, the fuel film thickness on the wall of the PFI engine was analyzed in two case studies.

Quality control of gasoline constituents and its effect on the Intake Valve Deposits (IVD) has become a recent issue. In this paper, the effects of gasoline and oil quality on intake valve deposits were investigated using an Intake Valve Deposit Test Bench and a Sludge Simulator. The deposit formation from the gasoline maximized at an intake valve temperature of approximately 160 °C, and the deposits formed from the engine oil were maximum at approximately 250 °C. Therefore, the contribution of the gasoline or the engine oil appears to depend on the engine conditions. The gasoline which contains MTBE or ethanol with no detergent additive slightly increases the deposition amount. The gasoline with a superior detergent significantly decreases the deposition amount even when MTBE or ethanol is blended in the gasoline. Appropriate detergent fuel additive retards the oil deterioration.

We have developed a new navigation system which utilizes voice synthesis function, and mounted it on the new model. This paper reports the details of the navigation system. The navigation system was developed with the aim of providing a system which is capable of reducing the load on the driver and helping reach the destination smoothly and more safely than the conventional system.

We have developed a new measurement apparatus designed to take orange-peel quality-assessment measurements of paint-finished surfaces on a non-contact basis. This apparatus was developed to determine the relationship between in-line spray-coating conditions and the resulting orange peel surface, and to optimally control/manage the conditions of our existing facilities to ensure the best possible coating results based on the obtained data. The apparatus has been implemented by adopting image analysis, which combines an optical system design based on human inspectors’ visual-checking conditions and a set of straightforward algorithms.

The purposes of this paper are to develop a new laboratory oxidation stability testing method and to clarify factors relative to the viscosity increase of engine oil. Polymerized products, obtained from the oil after a JASO M333-93 engine test, were found to consist mainly of carboxyl, nitrate and nitro compounds and to increase the oil viscosity. A good similarity between the JASO M333-93 test and the laboratory simulation test was found for the polymerized products. The products were obtained not by heating oil only in air but by heating oil while supplying a synthetic blowby gas consisting of fuel pyrolysis products, NO, SO2 and air. The laboratory test has also revealed that the viscosity increase depends on oil quality, organic Fe content and hydrocarbon composition in the fuel. Moreover, it has been found that blowby gas and organic Fe accelerate ZnDTP consumption and that aromatics concentration in the fuel correlates with the viscosity increase of oil.

High visibility electronic analog instruments with the blackface lens, lighting up pointers, and back lit dials are used in increasing number for automotive instrumentation. Now, we have developed a new instrument called Optical Space-Vision Instrumentation incorporating the above electronic analog instrument with virtual image by double reflection mechanism. The purpose of this development is to reduce reading time through far-focus and to improve visibility through high contrast. As part of this instrumentation, we also developed a new pointer that uses fluorescent material without a light-emitting element. This paper describes the construction and the engineering technology associated with this instrumentation. According to our test results, this instrument has realized a shorter reading time and higher contrast.

This paper contains an explanation of a Multiplex Wiring System with Optical Data-Link for cars, which has been installed in the Toyota “Century” since 1982. In this system, a total of 64 signals related to door wiring are transmitted in a multiplex fashion, and the number of wires from the front right-hand door to the interior could be reduced from 46 wires, which were used with conventional wiring techniques, to 10 wires including 2 plastic optical fibers. This system also has various control functions which includes a door-lock control function. In order to give high reliability to this system, we have developed a new optical data-link as well as a new custom micro-computer. And in the automobile industry, such a large scale multiplex wiring system having high reliability is very innovative in our opinion and will surely have a large impact in the future.

Toyota has developed a new full time 4WD system, called “EC-HYMATIC” or Electronically Controlled - HYdraulic Multi-plate clutch Active Traction Intelligent Control. This system permits an automatic torque transfer, depending on driving conditions, for front and rear wheels under control of the speed difference between the two. The system developed consists of a center differential, a speed difference control clutch system employing multi-plate clutch, and a gear set for rear axle drive. The speed difference control clutch system is controlled by a unique electro-hydraulic system using a microcomputer. An extensive use of computer simulations and vehicle test and evaluation has successfully developed an appropriate control strategy for the clutch system. The new 4WD system, EC-HYMATIC, considerably improves handling characteristics, traction performance and stability of a 4WD vehicle.

The characteristic of In-Cylinder gas motion of a multivalve engine is compared with a single intake valve engine, which have been predicted by a three-dimensional numerical simulation and flow visualization. The measured intake valve outlet velocity from helical and straight port was adopted as the boundary conditions. The computer graphics technique has been utilized to express the predicted numerical results as moving picture like visualized flow. This flow pattern was compared with the actual flow pattern visualized with metaldehyde as the tracer using the bottom viewed engine, which showed good agreement. The prediction for the multivalve engine showed that the swirl velocity is rapidly reduced by interaction between the flows from the two port, but the turbulence kinetic energy is similar to that in the engines with a single intake valve with helical port.

One-box type vehicles are especially liable to a loss of stability when entering a region of cross-wind. The reasons for this instability were investigated using scale models and by means of a mathematical simulation. Results indicated that yawing moment attains a peak at a precise position of the vehicle relative to the cross-wind. Visualization of the air flow and measurement of the pressure distributions established the cause of the phenomenon. Furthermore a study was conducted into the effects of body shape on stability and the efficacy of various modifications was assessed.

In recent years, advanced technology has become more and more important in the design of automobiles. Therefore, if we wish our products to continue to display their full potential to the people who buy them, thus ensuring customer satisfaction with our products, we must, even in the area of after-soles service, ensure that the technical proficiency and knowledge of our technicians will continue to keep pace with advances in technology. To do this, we must carry out effective “high-tech” training for our dealer workshops this is our present and future challenge Toyota's technical service training system is now applied to some 50, 000 service technicians in around 10, 000 workshops throughout the world, and the proposed report will introduce this system and give some actual examples of technical training that is actually carried out.

Road Departure Mitigation System (RDMS) is a new feature in vehicle active safety systems. It may not rely only on the lane marking for road edge detection, but other roadside objects This paper discusses the radar aspect of the RDMS testing on roads with grass road edges. Since the grass color may be different at different test sites and in different seasons, testing of RDMS with real grass road edge has the repeatability issue over time and locations. A solution is to develop surrogate grass that has the same characteristics of the representative real grass. Radar can be used in RDMS to identify road edges. The surrogate grass should be similar to representative real grass in color, LIDAR characteristics, and Radar characteristics. This paper provides the 24 GHz and 77 GHz radar characteristic specifications of surrogate grass.

The driving simulator (DS) developed by Toyota Motor Corporation simulates acceleration using translational (XY direction) and tilting motions. However, the driver of the DS may perceive a feeling of rotation generated by the tilting motion, which is not generated in an actual vehicle. If the driver perceives rotation, a vestibulo-ocular reflex (VOR) is generated that results in an unnecessary correction in the driver's gaze. This generates a conflict between the vestibular and visual sensations of the driver and causes motion sickness. Although such motion sickness can be alleviated by reducing the tilting motion of the DS, this has the effect of increasing the amount of XY motion, which has a limited range. Therefore, it is desirable to limit the reduction in the tilting motion of the DS to the specific timing and amount required to alleviate motion sickness. However, the timing and extent of the VOR has yet to be accurately identified.