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This paper describes the newly developed processes of low temperature wafer bonding using plasma activation and deep dry silicon etching technologies. Both processes are a new type of “MEMS” (Micro Electro Mechanical System) process technology suitable for automotive pressure sensors. The conventional pressure sensor was a unified unit consisting of a silicon sensor chip and a glass stage. The diced unified unit was cut from a bonded disk of a processed silicon wafer and a glass stage substrate, and the silicon sensor chip incorporated four piezo-resistors, a diaphragm and bipolar-circuit. However, the pressure sensor had difficulty in accurately measuring pressure in the high temperature range because of the thermal strain caused by the thermal expansion coefficient difference between the silicon sensor chip and the glass stage.

The automotive industry is placing high importance on technologies that can reduce CO2, even in a highly fuel-efficient compact car. One major technology is Stop & Start(S&S) System, with a combined energy regeneration system. A key component of the system is a power supply storage device that has high-charge acceptance, light weight, and compact size. We believe a Lithium-ion (Li-ion) battery completely meets these requirements. For the battery, there are three key points: 1 Battery cell specification 2 State Of Charge (SOC) detection method 3 Temperature management for Li-ion battery. We have already proposed the battery cell and the SOC detection during SAE 2013, and now we are going to introduce “Temperature Management”. If the temperature of a Li-ion battery operates over 60 degrees Celsius, the battery could be severely damaged. Therefore, temperature management of the battery is very important. Conventionally, the temperature is managed by several thermistors and a cooling fan.

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.

With the development of car electronics, increasing numbers of ECUs are mounted in vehicles and “function integration” and “unification of mechanical and electronic” are moving forward. In order for DENSO to supply customers with the optimum of these increasingly complex products, we use simulations from upstream processes, where there is a lack of design information, and are proceeding with the construction of virtual development environments in order to create products. This paper discusses these development techniques.

From the time the first Hybrid Vehicle (HV) was launched, 17 years have past, and HV vehicles have boosted the global CO2 reduction trend. In order to maximize their merit, many HV engines focused on the best fuel consumption value namely thermal efficiency. This was because HV systems can control the operating area of engine and get merit. However, considering climate change and energy issues, it is important to focus conventional vehicle as well as HV vehicle progress. The Atkinson cycle with a high compression ratio is the typical approach that HV engines use to enhance thermal efficiency. However, the drawback of the high compression ratio is a reduction of engine torque. Thermal efficiency at low load areas is relatively more important with conventional engines than with HV engines and how to overcome these issues is significantly important with conventional engines.

When fuel is vaporized and mixed well with air in the cylinder of premixed diesel engines, the mixture auto-ignites in one burst resulting in strong combustion noise, and combustion noise reduction is necessary to achieve high load premixed diesel engine operation. In this paper, an engine noise analysis was conducted by engine tests and simulations. The engine employed in the experiments was a supercharged single cylinder DI diesel engine with a high pressure common rail fuel injection system. The engine noise was sampled by two microphones and the sampled engine noise was averaged and analyzed by an FFT sound analyzer. The engine was equipped with a pressure transducer and the combustion noise was calculated from the power spectrum of the FFT analysis of the in-cylinder pressure wave data from the cross power spectrum of the sound pressure of the engine noise.

The purpose of this study is to analyze the piston skirt friction reduction effect of a diamond-like carbon (DLC)-coated wrist pin. The floating liner method and elasto-hydrodynamic lubrication (EHL) simulation were used to analyze piston skirt friction. The experimental results showed that a DLC-coated wrist pin reduced cylinder liner friction, and that this reduction was particularly large at low engine speeds and large pin offset conditions. Friction was particularly reduced at around the top and bottom dead center positions (TDC and BDC). EHL simulation confirmed that a DLC-coated wrist pin affects the piston motion and reduces the contact pressure between the piston skirt and cylinder liner.

As one of spark ignition (SI) engine solutions to improve fuel economy while maintaining drivability, concept of combing turbocharging and direct injection (DI) fuel injection system with engine down-sizing has increased its application in the market. Abnormal combustion phenomena referred to as Low Speed Pre-Ignition (LSPI) has been recognized as potential restriction to improve low speed engine torque that contributes fuel economy improvement. As reported in the part 1 [1], the study showed that engine oil composition had significant influence on the frequency of LSPI in both preventive and contributory effects. Further investigation was conducted to evaluate engine oil formulation variables and other factors that may have influences on the LSPI, such as engine oil degradation. Engine test that consisted of 2 phases was designed in order to confirm the correlation between LSPI frequency and engine oil degradation.

Due to increasing demands for further CO2 reduction and tighter exhaust emissions regulations, automakers are increasingly downsizing turbo-charged diesel engines by raising specific power, or adopting low-pressure loop exhaust gas recirculation (LPL-EGR) systems to improve the EGR rate. However, adopting a higher boost pressure to increase the specific power, or introducing hot exhaust gas before the turbocharger compressor with the LPL-EGR system creates higher gas temperatures in the compressor, which results in soot-containing deposits derived from the engine oil in the compressor. This phenomenon causes significant deterioration of turbocharger efficiency. Therefore, countermeasures such as restricting boost pressure or limiting EGR usage in the operational map are necessary to prevent engine performance deterioration. Increasing the gas temperature in the compressor while preventing deposit formation should enable further improvements in fuel consumption and engine power.

Previous reports have already described the details of engine start-shock and the mechanism of vibration mechanism in a stationary vehicle. This vibration can be reduced by optimized engine and motor generator vibration-reduction controls. A prediction method using a full-vehicle MBD model has also been developed and applied in actual vehicle development. This paper describes the outline of a new method for the hybrid system of mechanical power split device with two motors that predicts engine start-shock when the vehicle is accelerating while the engine is stopped. It also describes the results of mechanism analysis and component contribution analysis. This method targets engine start-shock caused by driving torque demand during acceleration after vehicle take-off. The hybrid control system is modeled by MATLAB/Simulink. A power management and motor generator control program used in actual vehicles is installed into the main part of the control system model.

This paper evaluates the effect of our new alternator concept for a conventional vehicle, which is able to generate electricity by storing kinetic energy of the vehicle in the high speed flywheel as rotation energy under deceleration. The alternator constructs a planetary gear device and multiple clutch-brakes perform CVT, alternator and high speed flywheel without an expensive electric device, mechanical CVT and vacuum pump. So it has high cost performance.

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.

Down-sizing and dielectric insulation were required for the traction motors of hybrid vehicles. By utilizing the newly developed coil with thick resin insulation atop the conventional enamel film, the use of conventional inter-phase insulation paper was abolished. Furthermore, by adopting the stair-shaped coil structure and spiral winding configuration, the stator size was minimized. With the above technologies, the motor installation to smaller hybrid vehicles was realized, thus contributing to weight reduction of hybrid vehicles.

In recent years, many various energy sources have been investigated as replacements for traditional automotive fossil fuels to help reduce CO2 emissions, respond to instabilities in the supply of fossil fuels, and reduce emissions of air pollutants in urban areas. Toyota Motor Corporation considers the plug-in hybrid vehicle (PHV), which can efficiently use electricity supplied from infrastructure, to be the most practical current solution to these issues. For this reason, Toyota began sales of the Prius Plug-in Hybrid in 2012 in the U.S., Europe and Japan. This is the first PHV to be mass-produced by Toyota Motor Corporation. Prior to this, in December 2009, Toyota sold 650 PHVs through lease programs for validation testing in the U.S., Europe and Japan. Additional 30 PHVs were introduced in China in March 2011 for the same objective.

After the Great East Japan Earthquake on March 11, 2011, Toyota Motor Corporation received considerable public response regarding the role of vehicles in emergencies from a large number of customers. These included comments about the usefulness of the electricity supply system in the Estima Hybrid during the long power outages caused by the earthquake. In response, Toyota decided to install this system in its other hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs). This system is capable of supplying power up to 1,500 watts, which means that it can be used to operate virtually every household electrical device. Since the engine starts automatically when the main battery capacity is depleted, a single vehicle can supply the daily power needs of a normal house in Japan for about four days, providing that the battery is fully charged and the fuel tank is full.

Increased interest in global warming requires rapid improvements in CO2 reduction efforts. The automotive industry is placing high importance on CO2 reduction technologies. Using Lithium-ion (Li-ion) battery pack Stop & Start (S&S) system with combined energy regeneration is an effective technology to reduce CO2 emissions. Power supply storage is very important for the S&S system. High charging acceptance, low weight, and compact size are required. A Li-ion battery is the optimal power supply that meets these requirements. It has high charge acceptance per weight. Furthermore, we developed simple system structure which eliminates the need for the DC-DC converter. By utilizing a Li-ion battery that has voltage characteristics similar to the Pb battery there is no need for a converter to make adjustments between the two power supplies. The Li-ion battery's range of capacity must be managed appropriately as overcharge and overdischarge causes extensive damage to the battery.

In recent years, fuel consumption regulations are becoming more severe in every country in the world. Engine size reduction plus turbo is one of the solutions. Our turbo system has an intercooler which cools high temperature gas compressed by a turbocharger. The structure of the intercooler is a tank mounted on both sides of a heat exchanger. The tank connects to the heat exchanger and turbo system allowing EGR (Exhaust Gas Recirculation) gas through the heat exchanger in response to the tightening of exhaust gas regulations. Use of the LPL (Low Pressure Loop) system which refluxes EGR gas is expected to increase from now. Since EGR gas is characterized by high temperature, high pressure, and acidic condensed water, high fatigue strength at high temperature and acid resistivity is required. Therefore aluminum (Al) is generally applied for “intercooler tank” (hereafter referred to as “tank”).

ESL (Electric System Level) Design Methodologies enable us to design and verify various electrical behaviors of automotive electronics including automotive semiconductors on a simulator before hardware prototyping. It could facilitate the optimization of hardware structures, and shorten the total development period by reducing rework process. We propose the “ESL Design Methodologies for Automotive” to renovate conventional development scheme. ESL technology began to be used from the domain of digital consumer electronics. Regarding automotive electronics domain, however, we would not be able to adapt the same methodologies to automotive systems, which consist of many mixed-signal components. Also, another approach is required for the rising demand of safety design sort of functional safety.

The development of the Lexus LFA focused on the pursuit of a passionate driving experience suitable for a super sports car. The shift speed control system in the LFA is an automated manual transmission (AMT) that uses an electrohydraulic actuator. The excellent shifting performance of the AMT was achieved by developing control technology that performs smooth, quick, and highly responsive shifting in accordance with the driving conditions. This was the result of repeated evaluations in both normal driving and on circuits featuring many acceleration, deceleration, and high-speed driving sectors. This paper describes the AMT shift speed control system and technology.

This paper describes an outline of the Toyota FCHV-adv, a fuel cell vehicle with a practical cruising range of more than 500 km. The cold startability of the FCHV-adv was improved by modifying the FC stack and control system. As a result, the FCHV-adv is capable of starting at a temperature of -30°C. In the future, Toyota intends to improve durability and reduce costs and is continuing to cooperate with governments and energy businesses to establish infrastructure and make the necessary modifications to laws and regulations.