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Exhaust and evaporative emissions systems have been developed to match the characteristics and usage of the Toyota THS II plug-in hybrid electric vehicle (PHEV). Based on the commercially available Prius, the Toyota PHEV features an additional external charging function, which allows it to be driven as an electric vehicle (EV) in urban areas, and as an hybrid electric vehicle (HEV) in high-speed/high-load and long-distance driving situations. To reduce exhaust emissions, the conventional catalyst warm up control has been enhanced to achieve emissions performance that satisfies California's Super Ultra Low Emissions Vehicle (SULEV) standards in every state of battery charge. In addition, a heat insulating fuel vapor containment system (FVS) has been developed using a plastic fuel tank based on the assumption that such a system can reduce the diffusion of vapor inside the fuel tank and the release of fuel vapor in to the atmosphere to the maximum possible extent.

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.

Vehicle body movements that occur during cornering have a strong influence on the evaluation of ride and handling. As a first step, we analyze subjective comments from trained drivers and find that the sense of vision played a major part in cornering feel. As a result of quantitative evaluations, we hypothesize that smaller time lag between roll angle and pitch angle made cornering feel better. We perform a human sensitivity evaluation, which confirmed this hypothesis. Given this result, we derive analytical equations for the roll center kinematics and the damping characteristics, in order to find a theoretical condition for the time lag of 0sec (giving a good cornering feel). We verify this by experiment.

Toyota has developed a new sports shift control system introduced in the world's first eight-speed automatic transmission (AA80E), which is implemented in the “LS 460” and has been adopted in the “IS F” (upcoming 2008 model). This enables the IS F to be a vehicle that also permits the enjoyment of driving on circuits as well as achieving that “fun-to-drive” image. In sports driving, as achieved by the conventional torque converter-type automatic transmissions, shift response performance for shift operation and linearity performance for accelerator operations were challenges to tackle. On the contrary, the newly developed sports shift control system has resolved these challenges and enables the IS F to be capable of responding to a driver's intention quickly and accurately, letting the driver truly experience satisfaction.

Grip feeling is an important facet in vehicle dynamics evaluation from a driver satisfaction and enjoyment standpoint. To improve grip feeling, we analyzed the subjective comments from test driver's about grip feeling and an evaluated human sensitivity to lateral motion. As a result, we found that drivers evaluate transient grip feeling according to the magnitude of lateral jerk. Next, we analyzed what vehicle parameters affect lateral jerk by using theoretical equations. As a result, we found that cornering power is an important parameter, especially the cornering power of rear tires as they can be create larger lateral jerk than can front tires.

A full vehicle multi-body dynamic (MBD) model with suspension control system is developed for fatigue life prediction under rough road condition. The model consists of tires, a trimmed body, heavy attached parts, powertrain, suspension, joints, and a driver model, and includes a suspension control system that varies characteristics of the suspension according to the rough road inputs. For tires, a commercial MBD tire model is employed with identifiable parameters. The models are simulated to run on the optically measured road surface of the proving ground. Apart from the trimmed body, several important heavy attached parts are modeled separately, that represent dynamic behavior that induces complex body input load. These parts, along with suspension and powertrain systems are connected to the body using nonlinear elements such as joints, springs, and dampers. Contact conditions are used to represent mount bushing, hood lock, stopper rubber, etc.

We have developed a New Black-face Cluster with Transparent EL Display, positioned on the speedometer, to display driver support information within the cluster; mass production of this DUAL VISION CLUSTER commenced in September 1999. The following were two requirements for implementing this cluster. 1) Selection of display device 2) Positioning of cluster in front of speedometer, using Transparent EL Display In this session, we will explain how we resolved the issues involved in development of this new Black-face Cluster. We will also describe the structure of the cluster.

Toyota Motor Corporation developed the Fuel Cell Hybrid Vehicle (FCHV). The FCHV-4 is an evolution of the conventional fuel cell vehicle that has made immense improvements in efficiency. Both a fuel cell and a secondary battery are used as sources of energy for the hybrid system. By using these energy sources proportionally, the system can be kept at or near its optimum state. The FCHV-4's system is designed to improve the efficiency and aims for high responsiveness when the vehicle is in a transitional state. In the same way as most electric vehicles, and as in the gasoline powered hybrid “Prius”, the energy the traction motor creates during breaking can be used to regenerate the secondary. The fuel cell and traction motor inverter are connected directly, with the secondary battery connected through the DC/DC converter to the fuel cell in parallel.

Development of a new battery system for Toyota Estima Hybrid, the world's first minivan hybrid vehicle, has been completed. The battery pack that consists of 30 nickel metal hydride battery modules is compactly arranged under the 3rd seat in the cabin along with components such as the battery cooling blower and the ducts. This arrangement was designed in consideration of user's vehicle use, passengers' comfort and efficient battery-cooling performance.

A highly reliable all-mechanical air bag system has been developed with a production cost lower than the electrical air bag system. All components, such as the bag, inflator and sensor are integrated into the steering wheel. Regarding the sensor design, we first discussed the requirements of the sensor to optimize the driver's protection, and then we designed it using a simulation method. We have confirmed by crash tests that this method is correct, and have found that this system is effective for reducing facial injuries.

A description is made of new control methods to improve response of wheel slip regulation. These methods enabled a new Traction Control (TRC) system based on throttle control rather than brake pressure to be developed. Major points are as follows: (1) Use of fuel injection cut-off to minimize delay (2) Additional adaptive throttle control logic By these means, a response nearly equal to that with brake pressure control is achieved at lower cost and with a considerable weight saving. Furthermore, the system, by suppressing noise and vibration, enhances the driver's control ability.

Instrument clusters used in automobiles play an important role as man-machine interface. A variety of information about the current driving situation is conveyed to the driver quickly and accurately. A great interest has been taken in the high visibility and legibility of the head-up display (subsequently abbreviated as HUD). Originally developed as display used in aeronautical applications, we have tried to exploit ways to adapt this device for automotive use. We have succeeded to produce a new HUD system, which has the following design features; (1) High brightness and high contrast display device using a liquid crystal display (subsequently abbreviated as LCD) and a halogen lamp illumination. (2) Long focus display in two colors using holographic lens. (3) Automatic dimming control system using an illuminance sensor. (see Fig. 1)

Vehicles have been more required to save energy against the background of the tendency of ecology. As the result of improving efficiency of internal combustion engines and adoption of electric power train, heat loss from engine coolant, which is used to heat the cabin, decreases and consequently additional energy may be consumed to maintain thermal comfort in the passenger compartment in winter. This paper is concerned with the humidity control system that realizes reduction of ventilation heat loss by controlling recirculation rate of the HVAC system by using highly accurate humidity sensor to evaluate risk of fogging on the windshield. As the results of the control, fuel consumption of hybrid vehicles decreases and maximum range of electric vehicles increases.

Achieving the speed and performance of a true supercar was merely the starting point of this development. In addition, the development also focused on achieving emotive performance attributes to enhance driver appeal. For this the engine was developed to assist a vehicle handling provides unsurpassed response, the creating a feeling of infinite acceleration potential, response is instantaneous and based on close understanding of driver's reactions and Awe inspiring sound is providing. It meets the latest emission standard Euro V and achieves good fuel consumption with a wide range stoechiometric air fuel ratio, till speeds up to 240km/h.

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.

In recent years, a number of different Blind Spot Monitor (BSM) systems have become more and more popular in North American automotive market. The BSM system advises the driver of vehicles travelling in adjacent lanes when these vehicles are also in the driver's outside rearview mirror blind spots. Similarly, when the vehicle is backing up from a parking spot, cross-traffic vehicles can be in the driver's outside mirror blind spots. In this situation, the Rear Cross Traffic Alert (RCTA) system alerts the driver when the driver shifts the vehicle in the reverse gear and there are approaching cross-traffic vehicles. The benefits of RCTA system was presented by [1]. The RCTA alert studied in this paper is given by playing an audible sound and by flashing the outside mirror indicators. The RCTA and BSM systems share the same vehicle sensors and most of their vehicle components.

These days, a variety of navigation systems have been developed to provide the driver with necessary information such as vehicle location, direction and destination. An electronic compass is being widely used as a component for such navigation systems (1), (2) and (3). Compared with a conventional magnetic compass, an electronic compass has the following advantages: 1. High vibration durability and quick response. 2. Easy to calibrate and reliable. 3. Sensor and display units can be separated. The electronic compass, however, is accompanied by two serious subjects: the development of a sensitive geomagnetic sensor, and calibration of direction error due to an unexpectedly magnetized vehicle body. First, we developed a new geomagnetic sensor utilizing magnetoresistive elements (MRE) and magnetic lenses. Next, we clarified the magnetic disturbances and defined the mechanism of vehicle magnetization, thereby establishing a simple calibration technique for such magnetization.

In the field of automotive body electronic control such as control of door locks, power windows, and wipers, there is a growing need of multiplexing communication to reduce the amount of wire harnesses. To meet this need, we developed a multiplexing communication protocol particularly suited to the body electronic control. Based on the developed protocol, we designed a communication control IC and a simple driver/receiver circuit with a few discrete components. The bus access method of the communication is the CSMA/CD with nondestructive bit arbitration, and its bit rate is 5 kbps. Its transmission media is a single wire. The communication IC has a multiplexing control block and a serial I/O block for an interface with a host CPU. It was fabricated using CMOS technology and has a chip of 2.6mm x 3.0mm in size that contains about 5,000 transistors. The driver/receiver circuit consists of one transistor, one capacitor and several resistors.

Display devices are required to have some fundamental functions which are brightness & gradation, colorfullness, resolution & sharpness, response time, and suitable size of the picture. Since the CRT (Cathode Ray Tube) is superior to the other display devices in these requirements, it can offer much information efficiently and effectively. Their visibility should not be evaluated only on the basis of some standards for office automation systems. From the point of view of human factors, visibility investigations of the CRTs for automobiles are examined. In this paper the relationship between the chromaticity difference and the luminance contrast for drivers to read the picture easily, and the luminance of the background in the CRTs for drivers not to be dazzled in the nighttime driving are clarified.