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In order to clarify future automobile technologies and fuel qualities to improve air quality, second phase of Japan Clean Air Program (JCAPII) had been conducted from 2002 to 2007. Predicting improvement in air quality that might be attained by introducing new emission control technologies and determining fuel qualities required for the technologies is one of the main issues of this program. Unregulated material WG of JCAPII had studied unregulated emissions from gasoline and diesel engines. Eight gaseous hydrocarbons (HC), four Aldehydes and three polycyclic aromatic hydrocarbons (PAHs) were evaluated as unregulated emissions. Specifically, emissions of the following components were measured: 1,3-Butadiene, Benzene, Toluene, Xylene, Ethylbenzene, 1,3,5-Trimethyl-benzene, n-Hexane, Styrene as gaseous HCs, Formaldehyde, Acetaldehyde, Acrolein, Benzaldehyde as Aldehydes, and Benzo(a)pyrene, Benzo(b)fluoranthene, Benzo(k)fluoranthene as PAHs.

This research developed a new measurement technology for thermal analysis of the heat radiation from a hybrid transaxle case surface to the air and improved the heat radiation performance. This heat flux measurement technology provides the method to measure heat flux without wiring of sensors. The method does not have effects of wiring on the temperature field and the flow field unlike the conventional methods. Therefore, multipoint measurement of heat flux on the case surface was enabled, and the distribution of heat flux was quantified. To measure heat flux, thermal resistances made of plastic plates were attached to the case surface and the infrared thermography was used for the temperature measurement. The preliminary examination was performed to confirm the accuracy of the thermal evaluation through heat flux measurement. The oil in the transaxle was heated and the amount of heat radiation from the case surface was measured.

The purpose of this paper is to construct the thermal analysis model by measuring and estimating the temperature at the traction contact area. For measurement of temperature, we have used a thin-film temperature sensor. For estimation of temperature, we have composed the thermal analysis model. The thin-film temperature sensor was formed on the contact surface using a spattering device. The sensor is constituted of three layers (sensor layer, insulation layer and intermediate layer). Dimensions of the sensor were sufficiently smaller than the traction contact area. The sensor featured high specific pressure capacity and high speed responsiveness. The thermal analysis model was mainly composed of three equations: Carslaw & Jaeger equation, Rashid & Seireg equation and heat transfer equation of shear heating in oil film. The heat transfer equation involved two models (local shear heating model at middle plane, homogeneous shear heating model).

In recent years, designers have attributed increasing importance to reducing noise in car interiors, and various improvements have led to a steady decrease each year in said interior noise. More recently, there has been abundant research on quantitative and qualitative approaches to interior noise, including studies on improving sound quality, such as elimination of rumbling noise and creating a feeling of linearity. Particularly engine noise, one of the major causes of interior noise, has been studied from various angles and significantly reduced in recent years. This has led in turn to increased interest in air induction noise which was a relatively minor noise source in the past. One method of reducing induction noise is the addition of several resonators to the induction system. Induction system components, including resonators, have a major effect on engine output and fuel consumption.

A closed loop lean limit control system by using engine roughness was studied. This system controls the air-fuel mixture close to optimum for fuel economy, which is a little richer mixture than lean misfire limit by measuring engine roughness using the information from engine speed signal. A magneto resistance type engine speed sensor was utilized as a roughness sensor and the engine roughness was calculated from that signal by a 12 bit micro-computer. It was found that the engine roughness correlated well with the variation of combustion on the dynamometer test. Some correlation measures to eliminate irregular fluctuations caused by load variations on the rough road driving condition or engine torque variations on the acceleration and deceleration condition of a vehicle, were applied to the micro-computer program. It was confirmed that the closed loop lean limit control system functioned satisfactorily. About 7% higher fuel economy than conventional system was obtained.

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.

This paper gives an outline of the steering assistance system (hereinafter, SAS) and a description of its key technology: the lane recognition algorithm. To accommodate a variety of driving styles, the SAS is equipped with a lane keeping assistance mode (LKA mode) and a lane departure warning mode (LDW mode) that can be selectively set by the driver. The former mode works in combination with adaptive cruise control (ACC) and carries the advantage of relieving the driving load that is placed on the driver. The latter mode has the benefit of reducing the danger of lane departure accidents caused by the driver dozing off and taking his eyes off the road. The newly developed lane recognition ECU has a simple hardware set-up of two 32-bit microcomputers. The lane recognition algorithm was constructed on the basis of a logic process that analyzes pattern edge points and selects a set of edge points that most closely resemble lanemarks.

The development of new systems to reduce exhaust gases is being investigated in response to OBD-II regulations and regulations all over the world relating to the introduction of low exhaust gas vehicles (LEV, ULEV, STEP3, STEP4). We have developed a highly responsive thermistor type catalyst temperature sensor that is very accurate, highly heat resistant, has a wide detection range, and that can be used in exhaust gas cleansing systems. The key technologies used in this new catalyst temperature sensor are: 1 Wide detection range: The thermistor is of a network construction that comprises a semi-conductor with a new Y-Cr-Mn perovskite crystal structure and an insulator. The temperature range can be set by changing the proportions of semi-conductor and insulator.

1 In general, the engine brake performance of a vehicle with an automatic transmission (AT) is inferior to that of a vehicle with a manual transmission (MT), without manually downshifting the transmission. Especially, in commercial vehicles having great variations in load capacity, improvements in engine brake performances are significant issues for vehicles with an AT in terms of both safety and performance. For such circumstances, Aisin Seiki has succeeded in the development of a 6-speed AT for commercial vehicles with an engine control system that enables the vehicle to decelerate according to desire of drivers in various driving conditions. An outline of the development of this control system is presented below.

Toyota Motor Corporation (TMC) has been developing fuel cell (FC) technology since 1992, and finally “MIRAI” was launched in 15th Dec. 2014. An important step was achieved with the release of the “FCHV-adv” in 2008. It established major improvements in efficiency, driving range, durability, and cold start capability. However, enhancing performance and further reductions in size and cost are required to facilitate the commercial widespread adoption of fuel cell vehicles (FCVs). TMC met these challenges by developing the world's first FC stack without a humidifying system. This was achieved by the development of an innovative cell flow field structure and membrane electrode assembly (MEA), enabling a compact and high-performance FC stack. Other cost reduction measures incorporated by the FC stack include reducing the amount of platinum in the catalyst by two-thirds and adopting a carbon nano-coating for the separator surface treatment.

Oil consumption mechanism was analyzed by measuring the radial movement of the upper side rail in a three piece type oil ring, together with the piston movement. Ultra-miniature inductive displacement sensors were designed to measure the oil ring movement and fitted on the upper side rail with a part of the 3rd land cut out. The clearance between the side rail and the cylinder wall was measured under various operating conditions. The results showed that the radial movement of the oil ring was affected by the piston movement, which results in the possibility of degrading the oil control ability for the cylinder wall because the oil ring temporarily moves with the piston. Accordingly, the designs to improve the piston movement or to be less affected by the movement proved to be an important factor for the reduction of the oil consumption.

In the case of two-stroke cycle gasoline engines, it is a rather well known fact that under light-load operation they do not run smoothly, but have a high concentration of unburned hydrocarbons (HC) in the exhaust gas, as well as high a fuel consumption rate. In the study to improve such unstable conditions by devising a scavenging process of the engine, we often encountered self-ignited combustion, a kind of “RUN-ON”. This combustion was found to be very stable and fine with low missions of HC, and improved fuel consumption. A study was carried out on this self-ignited combustion by optical analysis. Many differences were observed between self-ignited combustion and conventional spark ignited combustion on the behavior of formation of chemical intermediate products before and after ignition. Self-ignited combustion has been found to occur under relatively low cylinder pressure and temperature, compared to diesel engine combustion, presumably by virtue of intermediate products.