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Many accidents occur today when distant objects or roadway impediments are not quickly detected. To help avoid these accidents, longer-range safety systems are needed with real-time detection capability and without requiring a line-of-sight (LOS) view by the driver or sensor. Early detection at intersections is required for obstacle location around blind corners and dynamic awareness of approaching vehicles on intersecting roadways. Many of today's vehicular safety systems require short LOS distances to be effective. Such systems include forward collision warning, adaptive cruise control, and lane keeping assistance. To operate over longer LOS distances and in Non-LOS (NLOS) conditions, cooperative wireless communications systems are being considered. This paper describes field results for LOS and NLOS radio links for one candidate wireless system: 5.9GHz Dedicated Short Range Communications (DSRC).

The aim of this research is to develop the diesel combustion simulation (UniDES: Universal Diesel Engine Simulator) that incorporates multiple-injection strategies and in-cylinder composition changes due to exhaust gas recirculation (EGR), and that is capable of high speed calculation. The model is based on a zero-dimensional (0D) cycle simulation, and represents a multiple-injection strategy using a multi-zone model and inhomogeneity using a probability density function (PDF) model. Therefore, the 0D cycle simulation also enables both high accuracy and high speed. This research considers application to actual development. To expand the applicability of the simulation, a model that accurately estimates nozzle sac pressure with various injection quantities and common rail pressures, a model that accounts for the effects of adjacent spray interaction, and a model that considers the NOx reduction phenomenon under high load conditions were added.

There is ever increasing interest in the issues of fossil fuel depletion, global warming, due to increased atmospheric CO2, and air pollution, all of which are due in some extent to transportation, including automobiles. Hybrid Vehicles (HVs), whose performance and usage are equivalent to existing conventional vehicles, attract lots of attention and have started to come into wider use. Meanwhile, EVs have been considered by many as the best solution for the issues mentioned above. But the technical difficulty of battery energy density is an obstruction to successful implementation. Currently the Plug-in HV (PHEV), which combines the advantages of HV and EV, is being considered as one promising solution. PHEVs can be categorized into two types, according to operating modes. The first uses battery stored energy initially, only stating the internal combustion engine when the battery is depleted. This we call the All Electric Range (AER) system.

In this paper, we will introduce a stereo vision system developed as a sensor for a vehicle's front monitor. This system consists of three parts; namely, a stereo camera that collects video images of the forward view of the vehicle, a stereo ECU that processes its output image, and a near-infrared floodlight for illuminating the front at night. We were able to develop an obstacle detection function for the Pre-Crash Safety System and also a traffic lane detection function for a Lane-Keeping Assist System. Especially in regard to the obstacle detection function, we were able to achieve real-time processing of the disparity image calculations that had formerly required long processing times by using two types of recently developed LSIs.

The growing functionality and complexity of recent vehicle electronic systems have made inter-device communication (on-board LAN) technology vital to vehicle design. By field of application, the LAN (Local Area Network) systems currently in use are LIN (Local Interconnect Network) used for body systems, CAN (Controller Area Network) used for control systems, and MOST (Media Oriented Systems Transport ) used for multimedia and camera systems, and work to standardize the next-generation communication technology for each of those fields is underway. This paper provides a technical overview of the CXPI (Clock Extension Peripheral Interface) communication protocol, which satisfies the body system requirements (rapid response, system extensibility, high reliability, and low cost). It also presents the progress made on standardization at SAE and other organizations.

Many ICs are used in various electronic components in automotive applications, such as ECUs (electronic control units) and smart actuators. Automotive ICs required the following features: (1) high integration of analog, digital and output devices; (2) high breakdown voltage for analog devices standing the battery voltage; (3) highly accurate control for analog circuits; (4) susceptibility under harsh operating conditions, such as high ambient temperature and high humidity; and (5) high surge immunity such as ESD (electrostatic discharge) robustness. To meet these requirements, we developed analog and output devices with improved surge endurance based on SOI wafer and trench-dielectric-isolation technologies. Analog circuit applications, especially accurate power management or high-precision solenoid driving, demands stable temperature-compensated output. Load dump and battery-jumping also needs high voltage protection and high noise immunity for these devices.

Conventional methods of physicochemical models require various experts and a high measurement demand to achieve the required model accuracy. With an additional request for faster development time for diagnostic algorithms, this method has reached the limits of economic feasibility. Machine learning algorithms are getting more popular in order to achieve a high model accuracy with an appropriate economical effort and allow to describe complex problems using statistical methods. An important point is the independence from other modelled variables and the exclusive use of sensor data and actuator settings. The concept has already been successfully proven in the field of modelling for exhaust gas aftertreatment sensors. An engine-out nitrogen oxide (NOX) emission sensor model based on polynomial regression was developed, trained, and transferred onto a conventional automotive electronic control unit (ECU) and also proves real-time capability.

In 1997, we have applied laser technology to the world's first practical adaptive cruise control (ACC) system. The ACC system is based on 2-dimensional scanning laser-radar-sensor technology that is supported by highly reliable high power diode laser. Now, we have developed 34W output power multiple-quantum-well (MQW) diode laser. The power of 870nm near IR diode laser is twice as high as conventional one, thus it meets the strong needs for robust detection of the reflective laser beams from the moving vehicle ahead. Furthermore, Au-Sn-Ni a new alloy solder has been employed to sustain high degree of vibration and thermal shock to raise reliability. The acceleration life-tests at high temperature pulsed operation demonstrate the high reliability of developed 34W high power diode laser.

In applying a LAN to automotive electronics systems, an optimal protocol has been adopted for each system so far, such as body electronics system, entertainment system, service system and power train system. As low cost communication protocol “BEAN” (Body Electronics Area Network; SAE paper 970297) adopted to wider range of functions on vehicle, ECU's numbers are increased which have BEAN communication and that is branched to plural communication networks. We have succeeded in rationalization of those network systems with the gateway function on a delegated ECU for each LAN system on vehicle. And this system also realized the connection to after market products by data exchange through the gateway function, while securing vehicle fail-safe.

In order to evaluate the toughness of automotive ECU's to electrostatic discharge, a conventional method where electrostatic discharge pulse is applied to connector parts on a printed circuit board is commonly used. But quantitative re-designing principles to improve the static electricity tolerance have not been made clear that completely utilizes the test data shown below till now, because propagation mechanism of static electricity on a circuit board is not clear. This paper describes the ESD current measurement technique which detects the near magnetic field generated by ESD currents. We developed to measure the ESD currents using the new loop antenna on a circuit board. The ESD current, was generated with the static electricity applied to a model circuit pattern in conformity with IEC and ISO standard and measured using the antenna. Also it was able to visualize how static electricity energy would propagate through the circuit board.

For energy saving and global warming prevention, Toyota has developed Toyota Hybrid System (THS) for mass-produced passenger cars, which achieves drastic improvement in fuel efficiency and reduction in exhaust emissions compared to conventional gasoline engine cars. The THS has two motive power sources which engage depending on driving conditions. It's power is supplied either from an engine (controlled by the engine ECU) or an electric motor (controlled by the motor ECU) which is powered by a high-voltage battery (monitored by the battery ECU). These ECUs are controlled by a hybrid ECU. Each ECU has been developed with a fail-safe system in mind, to ensure driver safety in case of vehicle breakdowns. Among these ECUs, this paper reports particularly on the newly introduced ECUs: hybrid ECU and battery ECU. In the development of these ECUs, special attention was focused on fail-safe performance.

This paper introduces the cruise control system with distance control function, that is called Adaptive Cruise Control (ACC), that uses a scanning laser radar as a sensor to detect preceding vehicles. With the goal of increasing the driving convenience and comfort when compared to the conventional cruise control, lots of ACC systems have been proposed and developed. This paper presents ACC system using the scanning laser radar which was developed by Toyota, and describes the adaptation of the system specifications. This ACC system was able to greatly reduce the driver's work load, and increased the driver's convenience and comfort when operating the cruise controls system. In addition, we were able to design this system to be highly dependable and inexpensive and supply it to the market as a result of incorporating various ideas for improvements.

Application of SiC power devices is regarded as a promising means of reducing the power loss of power modules mounted in power control units. Due to those high thermostable characteristics, the power module with SiC power devices are required to have higher operating temperature than the conventional power module with Si power devices. However, the limitations of current packaging technology prevent the utilization of the full potential of SiC power devices. To resolve these issues, the development of device bonding technology is very important. Although transient liquid phase (TLP) bonding is a promising technology for enabling high temperature operation because its bonding layer has a high melting point, the characteristics of the TLP bonding layer tend to damage the power devices. This paper describes the development of a bonding technology to achieve high temperature operation using a stress reduction effect.

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.

An unique diesel engine electronic control system has been developed, which contains two distinctive features. Firstly, the delivery type fuel injection pump has an electro-magnetic valve to control the quantity of fuel injected. This valve is then acutuated to ensure that the timing of the high pressure fuel flow out stops the fuel injection. In the previous diesel electronic control system, the fuel quantity control was effected via the position control of a mechanical spill ring. Since timing control is more suitable than position control for handling by a microcomputer, the electro-magnetic valve is able to control the quantity of fuel injected more precisely, whilst consisting of a simpler structure. Secondly, an optical combustion timing sensor is able to detect initial combustion timing by sensing the light of the combustion flame in the combustion chamber. Using the signal from the sensor, the microcomputer then exerts a compensating control over the fuel injection timing.

The lateral DMOS (LDMOS) had been developed for intelligent power IC[1][2] for ECU (Electric Control Unit). The process and device simulation methodology are used while developing a devices. The physical model and parameter in analytical model are calibrated to enhance the accuracy of the simulation and to reduce lead time and costs.

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.

Toyota Motor Corporation has developed a new battery electric vehicle (BEV) on the dedicated e-TNGA platform for BEVs, which was designed to lower the center of gravity of the vehicle and increase body stiffness. In addition to a full-time 4WD system, another feature of this new BEV is its pleasurable driving experience. A new inverter drive unit was developed for this system. Unlike the previous inverter, the advantage of the new inverter is that it is small enough to be mounted inside the transaxle housing, thereby contributing to the availability of interior and luggage space. The temperature rise of the power semiconductors in the inverter was reduced considerably by the development of a new power semiconductor for BEVs. This enables a parallel layout of two power semiconductors instead of three. The components of the inverter were also downsized. A coreless current sensor was adopted, and capacitors were developed with significantly lower capacitance.

This paper describes a design tool and a software platform for FlexRay systems that are investigated in Nagoya University and are proposed to JasPar. The design tool reads the specification of a system as a task graph that consists of a set of tasks and messages among them. The design tool, then, allocates the tasks to ECUs and schedules the messages on a FlexRay network. The software platform consists of a middleware called time-trigger module (TTM) which dispatches time-triggered tasks, a communication middleware for a time-triggered network (TT-COM), a network management middleware for FlexRay (FlexRay-NM), and a device driver for FlexRay controller.

Up to now, while automobile electric packages have demanded the high density for small and light products, electric leaks, which have occurred due to condensation, have been a major problem. To prevent any electric leaks, a conformal coating on the electric parts (ex. ECU: Electronic Control Unit) has been needed, but in general the design rules of the conformal coating (ex. Application area) is vague. Therefore, DENSO demands to clear the design rules of conformal coating electric package for higher reliability. To meet the demand, DENSO has developed a condensation simulation method using CAE that can show the occurrence condition of condensation fast and accurately. In the result, DENSO has been able to get the design rules where to need the conformal coating in the electric package for automobiles.