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Previous studies have investigated the impacts of biofuel usage on the performance, drivability and durability of modern diesel engines and exhaust after-treatment systems including test work with different types, concentrations and mixtures of bio fuel components. During this earlier work vehicle fuel filter blocking issues were encountered during a field trial using various types of EN 14214 compliant Fatty Acid Methyl Ester (FAME) blended into EN 590 diesel. This paper summarises a subsequent literature review that was carried out looking into potential causes of this filter blocking and further work that was then carried out to expand on the findings. From this, a laboratory study was carried out to assess the increase in fuel filter blocking tendency (FBT) when various FAMEs from mixed sources were blended into EN 590 diesel at different concentrations, including levels above those currently allowed in the European market.

The AUTomotive Open System ARchitecture (AUTOSAR) Development Partnership has published early 2008 the specifications Release 3.0 [1], with a prime focus on the overall architecture, basic software, run time environment, communication stacks and methodology. Heavy developments have taken place in the OEM and supplier community to deliver AUTOSAR loaded cars on the streets starting 2008 [2]. The 2008 achievements have been: Improving the specifications in order to secure the exploitation for body, chassis and powertrain applications Adding major features: safety related functionalities, OBD II and Telematics application interfaces.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Due to the global economic downturn and higher environmental awareness, the social demands for low cost and fuel efficient vehicles are increasing. At the same time the engine power is increasing and customer expectations of reliability and NVH levels are increasing. To meet all the requirements, engineers are challenged to design light weight parts with higher performance. However, unconsidered mass reduction carries a risk of compromised NVH, Functional Reliability, and other functional demands. In order to resolve this contradiction, it is important to establish a basic structure with minimum necessary mass at the concept design phase, when there are still many degrees of freedom in the design space. Hence, a multi-objective optimization CAE methodology applicable for designing the basic structure of the Engine system was developed and is detailed below.

Teammate Advanced Drive is a driving support system with state-of-the-art automated driving technology that has been developed for customers’ safe and secure driving on highways based on the Toyota’s Mobility Teammate Concept. This SAE Level 2 (L2) system assists overtaking, lane changes, and branching to the destination, in addition to providing hands-free lane centering and car following. The automated driving technology includes self-localization onto a High Definition Map, multi-modal sensing to cover 360 degrees of the surrounding environment using fusion of LiDARs, cameras, and radars, and a redundant architecture to realize fail-safe operation when a malfunction or system limitation occurs. High-performance computing is provided to implement deep learning for predicting and responding to various situations that may be encountered while driving.

Over the past decades, the automotive industry has made significant efforts to improve engine fuel economy by reducing mechanical friction. Reducing friction under cold conditions is becoming more important in hybrid vehicle (HV) and plug-in hybrid vehicle (PHV) systems due to the lower oil temperatures of these systems, which results in higher friction loss. To help resolve this issue, a new internal gear fully variable discharge oil pump (F-VDOP) was developed. This new oil pump can control the oil pressure freely over a temperature range from -10°C to hot conditions. At 20°C, this pump lowers the minimum main gallery pressure to 100 kPa, thereby achieving a friction reduction effect of 1.4 Nm. The developed oil pump achieves a pressure response time constant of 0.17 seconds when changing the oil pressure from 120 kPa to 200 kPa at a temperature of 20°C and an engine speed of 1,600 rpm.

Mass reduction of parts is growing in importance as a means for reducing CO2 emissions from vehicles.The aim of the present research was to contribute to further mass reduction of pistons by developing a new aluminum casting material with highest level of fatigue strength. This goal was achieved using a development concept of creating a homogeneous structure in which Ti was added to create a fine structure and appropriate quantities of Fe and Mn were added to form a compound that is stable at high temperatures. Stand-alone tests of prototype pistons fabricated using the developed material show that the material is 14% stronger than the conventional material, thereby enabling increases in power and mass reduction.

The new P710 hybrid transaxle for a mid-size 2.5-liter class vehicle was developed based on the Toyota New Global Architecture (TNGA) design philosophy to achieve a range of desired performance objects. A smaller and lighter transaxle with low mechanical loss was realized by incorporating a new gear train structure and a downsized motor. The noise of the P710 transaxle was also reduced by adopting a new damper structure.

One way to improve the fuel efficiency of HVs is to reduce the losses and size of the Power Control Unit (PCU). To achieve this, it is important to reduce the losses of power devices (such as IGBTs and FWDs) used in the PCU since their losses account for about 20% of the total loss of an HV. Furthermore, another issue when reducing the size of power devices is ensuring the thermal feasibility of the downsized devices. To achieve the objectives of the 4th generation PCU, the following development targets were set for the IGBTs: reduce power losses by 19.8% and size by 30% compared to the 3rd generation. Power losses were reduced by the development of a new Super Body Layer (SBL) structure, which improved the trade-off relationship between switching and steady-state loss. This trade-off relationship was improved by optimizing the key SBL concentration parameter.

Toyota Motor Corporation began leasing a new generation fuel cell vehicle the FCHV (Fuel Cell Hybrid Vehicle) in December 2002. That vehicle includes a new variable voltage power electronics system and uses the Nickel Metal Hydride (Ni-MH) battery system from the Prius hybrid gasoline electric vehicle. This paper describes on-going efforts to model optimum secondary storage systems for future vehicles. Efficiency modeling is presented for the base Ni-MH storage system, an ultra capacitor system and a Lithium ion (Li-ion) battery system. The Li-ion system in combination with a new high efficiency converter shows a 4% improvement in fuel economy relative to the base system. The ultra capacitor system is not as efficient as the base system.

Toyota Motor has developed a new compact class hybrid vehicle (HV). This vehicle incorporates a new hybrid system to improve fuel efficiency. For this system, a new power control unit (PCU) has been developed that is downsizing, lightweight, and high efficiency. It is also important to have a highly adaptable function that can be applied to various car models. This paper describes the development of PCUs that play an important role in new systems.

Toyota Motor Corporation has developed the new compact-class hybrid vehicle (HV). This vehicle incorporates a new hybrid system for the improvement of fuel efficiency. For this system, a new Power Control Unit (PCU) is developed. The feature of the PCU is downsizing, lightweight, and high efficiency. In expectation of rapid popularization of HV, the aptitude for mass production is also improved. The PCU, which plays an important role in the new system, is our main focus in this paper. Its development is described.

In order to improve the fuel efficiency of Hybrid Electric Vehicles (HEVs), it is necessary to reduce the size and power loss of the HEV Power Control Units (PCUs). The loss of power devices (IGBTs and FWDs) used in a PCU accounts for approximately 20% of electric power loss of an HEV. Therefore, it is important to reduce the power loss while size reduction of the power devices. In order to achieve the newly developed PCU target for compact-size vehicles, the development targets for the power device were to achieve low power loss equivalent to its previous generation while size reduction by 25%. The size reduction was achieved by developing a new RC-IGBT (Reverse Conducting IGBT) with an IGBT and a FWD integration. As for the power loss aggravation, which was a major issue due to this integration, we optimized some important parameters like the IGBT and FWD surface layout and backside FWD pattern.

This paper describes the development of dummy FE models to be used for side impact simulations. The precise geometries of the ES-2re dummy and the SID-IIs dummy were measured at a pitch of 1.0 mm using X-ray CT scan. The material properties and the mechanical responses of the components were measured in static and dynamic tests and were used for the model validation. The models were further validated to US-NCAP side impact requirements. Good correlation was seen for both response time history, and to peak deformation values. It is shown that modeling the precise dummy internal structure in addition to the external geometry and applying accurate material properties enabled simulation of deformation kinematics and load transfer inside the dummies. As a result, it was possible to accurately simulate the injury value time histories in an actual test, and understand the mechanisms causing changes to the loading.

Weight reduction for a fuel cell vehicle (FCV) is important to contribute a long driving range. One approach to reduce vehicle weight involves using a carbon fiber reinforced plastic (CFRP) which has a high specific strength and stiffness. However, a conventional thermoset CFRP requires a long chemical reaction time and it is not easy to introduce into mass production vehicles. In this study, a new compression-moldable thermoplastic CFRP material for mass production body structural parts was developed and applied to the stack frame of the Toyota Mirai.

The GS450h requires higher system voltage to increase the motor output. For the insulated gate bipolar transistor (IGBT) that serves as the built-in switching device in the intelligent power module (IPM), higher voltage means greater loss and a larger device surface area, and it can also reduce the vehicle's fuel economy performance and increase its cost. To solve these issues, IGBT losses were reduced by (1) using a trench structure to make the IGBT more compact and (2) using a new structure in which the concentration of impurities in the drift layer is optimized. As a result, the device surface area was reduced by 10%, losses were reduced by 14%, and improved vehicle performance was achieved.

This paper describes the development of a new e-AWD hybrid system developed for SUVs. This hybrid system consists of a high-torque 2.4-liter turbocharged engine and a front unit that contains a 6-speed automatic transmission, an electric motor, and an inverter. It also includes a rear eAxle unit that contains a water-cooled high-power motor, an inverter, and a reduction gear, as well as a bipolar nickel-metal hydride battery. By combining a turbo engine that can output high torque across a wide range of engine rpm with two electric motors (front and rear), this system achieves both smooth acceleration with a torquey driving feeling and rapid response when the accelerator pedal is pressed. In addition, new AWD control using the water-cooled rear motor realized more stable cornering performance than the previous e-AWD system.

Toyota is implementing various technical developments in various fields for protection of environment. Reducing the fuel consumption is a matter of great urgency for the reduction of CO2 emissions. In the technology of vehicle body development, mass reduction and the improvement of aerodynamics are mainly important for fuel economy. As the one of way for this, we adopted resin glass as the back door glass of ES3, small-sized low-fuel consumption vehicle. (Figure 1,2,3) The first advantage of resin glass is the low density that weights about a half of inorganic glass. However resin glass is needed higher thickness for equivalent rigidity, as the result approximately 41% mass reduction was achieved. However resin glass is relatively expensive. Therefore it seems to be difficult to expand the usage of resin for this application. Then, we focused on additional advantage of resin glass, in order to make good use of resin glass. The second advantage of resin glass is design flexibility.

It is necessary for us to reduce CO2 emissions in order to hold down global warming which is advancing year by year. Toyota Motor Corporation believes that not only the introduction of BEVs but also the sale of the hybrid vehicles must spread in order to achieve the necessary CO2 reduction. Therefore, we planned to improve the attractiveness of future hybrid vehicles. Prius has always made full use of hybrid technologies and leading to significant CO2 reduction. Toyota Motor Corporation has developed a 2.0L hybrid system for the new Prius. We built the system which could achieve a comfortable drive along following the customer’s intention while improving the fuel economy more than a conventional system. The engine improves on both output and thermal efficiency. The transaxle decreases mechanical loss by downsizing the differential, and adoption of low viscosity oil.

An investigation of throttle response of engines during warm-up was conducted using various gasolines. Test data were obtained from an engine on a test bench at intermediate temperature around 20∼ 30 °C. By using the engine test bench data, correlation coefficients between engine response time and gasoline characteristics were calculated. The result shows that the middle range of distillation temperature is an important factor in gasoline characteristics for warm-up driveability of fuel injected engines. It also shows that 50% distillation temperature can be used as one indication of warm-up driveability. This indication is effective only for hydrocarbon type gasolines. In the case of MTBE blended gasoline, the distillation temperature becomes low when MTBE is blended to gasoline, but throttle response was not improved. It is also found that the effect of gasoline distillation on throttle response is enhanced by intake valve deposits.