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In order to correspond to the exhaust emissions regulations that become severe every year, more advanced engine control becomes necessary. Engine engineers are concerned about the Hydrocarbons (HCs) that flow through the air-intake ports and that are difficult to precisely control. The main sources of the HCs are, the canister purge, PCV, back-flow gas through the intake valves, and Air / Fuel ratio (A/F) may be aggravated when they flow into the combustion chambers. The influences HCs give on the A/F may also grow even greater, which is due to the increasingly stringent EVAP emission regulations, by more effective ventilation in the crankcase, and also by the growth of the VVT-operated angle and timing, respectively. In order to control the A/F more correctly, it is important to estimate the amount of HCs that are difficult to manage, and seek for suitable controls over fuel injection and so on.

On board multiplexing communication system is regarded as a necessary technology for the future of electronic system in automobiles. Many companies are developing multiplexing systems and the ISO and SAE are active in establishing standards for communication protocols. The proposed communication protocol specifications have different specifications. Consequently, no compatible evaluation standards existed, and it was difficult to compare one protocol to another. Therefore, to assist the standardization activities of the IS0 and SAE, we have developed an evaluation method for distributed multiplexed communication systems and evaluated each of the proposed protocols using this method. These evaluations were performed from the point of view of the future users of these systems. In this paper we present the results of the experiments on distributed multiplexed communication systems each of which consists of communication IC and the proposed physical layer.

Vehicle stability after releasing the accelerator during limit cornering (from now on “Tuck-in”) is the behavior that the turning radius of a vehicle gets smaller after releasing the accelerator. This paper presents that the main factors of yaw moment variation by releasing the accelerator are the change of lateral forces due to longitudinal transfer of normal loads, lateral shift of vehicle center of gravity due to vehicle roll and tire lateral deflection, and the change of lateral forces due to deceleration. It also shows that roll stiffness distribution and longitudinal acceleration have an influence through the formulation of turning radius ratio.

Toyota participated in Formula One1 (F1) Racing from 2002 to 2009. As a result of the downturn in the world economy, various engine developments within F1 were restricted in order to reduce the cost of competing in F1. The limit on the maximum number of engines allowed has decreased year by year. Toyota focused on the engine performance deterioration due to the combustion chamber deposits. In 2009, Toyota was successful in reducing around 40% of the deterioration by making combustion chamber cleaner in cooperation with ExxonMobil. This contributed to good result of 2009 F1 season for Toyota, including two second place finishes.

The recent growth of available computational resources has enabled the automotive industry to utilize unsteady Computational Fluid Dynamics (CFD) for their product development on a regular basis. Over the past years, it has been confirmed that unsteady CFD can accurately simulate the transient flow field around complex geometries. Concerning the aerodynamic properties of road vehicles, the detailed analysis of the transient flow field can help to improve the driving stability. Until now, however, there haven’t been many investigations that successfully identified a specific transient phenomenon from a simulated flow field corresponding to driving stability. This is because the unsteady flow field around a vehicle consists of various time and length scales and is therefore too complex to be analyzed with the same strategies as for steady state results.

This paper describes the multiplex communication protocol, BEAN (Body Electronics Area Network), developed for body control system on passenger cars which in recent years has increased the scope of multiplex communication. BEAN is based on a protocol developed in 1992 (SAE920231) but expands upon the performance in areas, such as the suitability of the ID system for increase of ECUs, the variable data length enabling the transmission of diagnostic data, and the transmission rate, while keeping the cost and radiation noise level low. The software size of BEAN is compact enough to be implemented by general purpose 8bit MCUs which have recently seen improvements in performance. The BEAN communication devices are available corresponding to the scale of the application and configuration of the ECU taking into account the software capability. This protocol was evaluated using simulation with the body control system on luxury passenger cars.

Wind noise is becoming a higher priority in the automotive industry. Several past studies investigated whether Statistical Energy Analysis (SEA) can be utilized to predict wind noise. Because wind noise analysis requires both radiation and transmission modeling in a wide frequency band, turbulent-structure-acoustic-coupled-SEA is being used. Past research investigated coupled-SEA’s benefit, but the model is usually simplified to enable easier consideration on the input side. However, the vehicle is composed of multiple interior parts and possible interior countermeasure consideration is needed. To enable this, at first, a more detailed coupled-SEA model is built from the acoustic-SEA model which has a larger number of degrees of freedom for the interior side. Then, the model is modified to account for sound radiation effects induced by turbulent and acoustic pressure.

Vehicles equipped with in-wheel motors are being studied and developed as a type of electric vehicle. Since these motors are attached to the suspension, a large vertical suspension reaction force is generated during driving. Based on this mechanism, this paper describes the development of a method for independently controlling roll and pitch as well as yaw using driving force distribution control at each wheel. It also details the theoretical calculation of a method for decoupling the dynamic motions. Finally, it describes the application of these 3D dynamic motion control methods to a test vehicle and the confirmation of the performance improvement.

1G engine series consists of four types of 2-liter, in-line, 6-cylinder gasoline engines for passenger cars, with different performance characteristics to meet diversified market demands. These engines are already put into mass production. The original engine - 1G-EU - is a compact and light weight 2-valve OHC engine with the maximum power 77 kW/5200 rpm. The 1G-GEU is a 4-valve DOHC engine developed on the basis of the 1G-EU engine, with a higher performance and a higher power of 103 kW/6200 rpm. The 1G-GZEU is a mechanical supercharging type engine based on the 1G-GEU, with a remarkably improved performance in the low and medium engine speed ranges, and the highest power of 110 kW/6000 rpm. The 1G-GTEI! is a turbocharging type engine also based on the 1G-GEU, with a markedly improved performance in the medium and high speed ranges, and the high power of 136 kW/6200 rpm. A number of new technologies were introduced on development of these engines.

The authors, et al. have succeeded in the practical application of the abradable flame spray coating, used in aircraft engines for the prevention of air leakage and the improvement of efficiency, to automobile turbochargers for the first time in the world. Two layers consisting of a bond coated layer and an abradable layer used to be coated by separate spray nozzles under the conventional technique. In this paper, equations of relations between various flame spray coating conditions and the quality of coated film, which were derived from measured results, will be described. Flame spray coating conditions, that allow the double layer coating by the same spray nozzle, have been determined for each layer. Temperatures and speeds of the flame were measured by means of two-color type high-speed cameras, and equations of their relations with the flame spray coating conditions are derived from the measured result.

Recently, there has been a tendency of high power and high speed in automotive engines. In addition they have been also required high reliability. And engine bearings have been required to be advanced in wear resistance as well as seizure resistance. Therefore, copper-lead alloy bearings with overlay, which have better seizure resistance, have been widely used for high speed engines up to the present. But it becomes very important for them to advance the overlay wear resistance. In this paper, the composite overlay is mainly researched to improve wear resistance regarding kind of hard particles and their amounts in the overlay.

The new Toyota FCV “Mirai” has reduced the weight, size, and cost of the high-pressure hydrogen storage system while improving fueling performance. The four 70 MPa tanks used on the 2008 Toyota FCHV-adv were reduced to two new larger diameter tanks. The laminated structure of the tanks was optimized to reduce weight, and a high-strength low-cost carbon fiber material was newly developed and adopted. The size of the high-pressure valve was reduced by improving its structure and a high-pressure sensor from a conventional vehicle was modified for use in a high-pressure hydrogen atmosphere. These innovations helped to improve the weight of the whole storage system by approximately 15% in comparison with Toyota FCHV-adv, while reducing the number of component parts by half and substantially reducing cost. The time required to fuel the FCV was greatly reduced by chilling the filling gas temperature at the hydrogen filling station to −40°C (as per SAE J2601).

Toyota Hybrid System (THS), that combines a gasoline engine and an electric motor was installed in the Prius, which was introduced in 1997 as the world's first mass-produced hybrid passenger car, and was vastly improved in 2003. The new Prius gained a status of highly innovative and practical vehicle. In 2005, combined with a V6 engine, THS had a further evolution as a Hybrid System for SUV, which was installed in the RX400h and Highlander Hybrid to be introduced into the world. This report will explain “new THS” which achieved both V8 engine power performance and compact class fuel economy, while securing the most stringent emission standard, SULEV.

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.

In the field of automotive gasoline engines, new products aiming at greater fuel economy and cleaner exhaust gases are under development with the aim of preventing environmental destruction. Severe ignition environments such as lean combustion, stronger charge motion, and large quantities of EGR require ever greater combustion stability. In an effort to meet these requirements, an iridium plug has been developed that achieves high ignitability and long service life through reduction of its diameter, using a highly wear-resistant iridium alloy as the center electrode.(1)(2) Recently, direct injection engines have attracted attention. In stratified combustion, a feature of the direct injection engine, the introduction of rich air-fuel mixtures in the vicinity of the plug ignition region tends to cause carbon fouling. This necessitates plug carbon fouling resistance.

We developed a fastening method to reduce noise levels and fastening work loads. The development was based on research into improved tools and fasteners. This was done in preparation for an increase in elderly worker and female worker population in the Automobile Assembly Shop. The principle of this method is to form female threads inside a straight sleeve by clinching the sleeve around a threaded bolt. We achieved improvements in component material clinching force and a durability for loosening torque compared to conventional bolt and nut methods.

Automotive Shredder Residue (ASR), the waste generated by shredding operations in the recycling of metals from scrapped automobiles, is currently disposed of in landfill sites. In Japan, disposal regulations such as leachable lead control have been changed, and moreover landfill sites are getting scarce. Therefore how to control, treat and decrease ASR is a serious matter. This study presents methods for the recycling of automotive shredder residue into automobile components by dry mechanical processing steps. These steps sort the material into several categories accrding to its properties. The material fineness is improved by further, thorough, sorting steps.

Computer aided systems for performance evaluation of functional devices for passenger cars, such as engines or transmissions, have been applied for ten years. These systems generally consist of a large main frame computer or minicomputers for conducting a large number of complicated analyses. In the past, these computer aided systems were used for vehicle research and development since they were too expensive and sophisticated for use on the production line. Today, microcomputers with mass memory or personal computers are available at very low cost in comparison to conventional minicomputers. With many distributed microcomputers, we have developed a new test and control system for the engine production line. This system consists of (1) a microcomputer with a disk system for test data storage, (2) five personal computers for the man-machine system and data processing, and (3) microcomputers for real time control and data acquistion.

Social concern with traffic accidents caused by driver’s medical emergencies has been growing for the last several years. In Japan, the government issued technical guidelines in June 2016 to promote systems that deal with such accidents. Based on those guidelines, the Emergency Stop Assist system was manufactured in October 2017 to help reduce such accidents. This article first describes its purpose and core design, then presents an overview of the system, and finally discusses its effectiveness.

We urgently need to develop the next generation of automotive technology to support energy conservation and the global environment. For this we need an advancement of the Laboratory Automation System (LAS). However, restructuring the hardware and software of the LAS requires enormous amounts of time and costs. To solve the problems of the LAS development, we formed a user-vendor working group, which then established the common rules of LAS and IMACS (Integrated Measurement And Control System). IMACS are software-centered rules, characterized by the stratification of LAS and the interface called software parts. So far, we have integrated IMACS into five engineering fields. A total of 11 testing machine vendors participated in the development. We manufactured about 350 software parts and made their specifications openly available. As the next step, we are collecting software parts by deleting redundant functions.