Search Results

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.

The rapid increase in the sophistication of vehicle automation demands development of evaluation protocols tuned to understanding driver-automation interaction. Driving simulators provide a safe and cost-efficient tool for studying driver-automation interaction, and this paper outlines general considerations for simulator-based evaluation protocols. Several challenges confront automation evaluation, including the limited utility of standard measures of driver performance (e.g., standard deviation of lane position), and the need to quantify underlying mental processes associated with situation awareness and trust. Implicitly or explicitly vehicle automation encourages drivers to disengage from driving and engage in other activities. Thus secondary tasks play an important role in both creating representative situations for automation use and misuse, as well as providing embedded measures of driver engagement.

The Deep Orange framework is an integral part of the graduate automotive engineering education at Clemson University International Center for Automotive Research (CU-ICAR). The initiative was developed to immerse students into the world of an OEM. For the 6th generation of Deep Orange, the goal was to develop an urban utility/activity vehicle for the year 2020. The objective of this paper is to describe the development of a multimaterial lightweight Body-in-White (BiW) structure to support an all-electric powertrain combined with an interior package that maximizes volume to enable a variety of interior configurations and activities for Generation Z users. AutoPacific data were first examined to define personas on the basis of their demographics and psychographics.

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.

Fuel efficiency improvement measures are focusing on both cold and hot conditions to help reduce CO2 emissions. Recent technological trends for improving fuel economy such as hybrid vehicles (HVs), engine start and stop systems, and variable valve systems feature expanded use of low-temperature engine operation regions. Under cold conditions (oil temperature: approximately 30°C), fuel consumption is roughly 20% greater than under hot conditions (80°C). The main cause of the increased friction under cold conditions is increased oil viscosity. This research used the motoring slipping method to measure the effect of an improved crankshaft bearing, which accounts for a high proportion of friction under cold conditions. First, the effect of clearance was investigated. Although increasing the clearance helped to decrease friction due to the oil wedge effect, greater oil leakage reduced the oil film temperature increase generated by the friction.

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.

The authors have developed a measurement technique equipped with new digital telemeter for strain, motion and temperature of engine parts under high speed running operation with high accuracy. This telemeter has an original signal processing method in which the sensor outputs are directly converted to digital signals without conventional amplifiers and A/D converters. This telemeter enables multipoint measurements at high engine speed in small gasoline engines because of its compactness and lightweight. And this enables long hours of engine test without concern over battery life because of its low power consumption and self-contained power generation. We applied new developed digital telemeter to several measurements and analysis on the piston, piston ring and connecting rod.

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.

Environmental improvement is moving forward, due in part to the reduction of fuel consumption of automatic transmission(AT) vehicles as a result of social requirements in recent years and many measures have been implemented. Adoption of idling stop is a typical example introduced to reduce energy consumption while the vehicle is stopped to improve the urban environment. However, there are problems such as responsiveness and smoothness for an AT vehicle when the engine is stopped with the shift selector in “D” range. To overcome these problems, a new start clutch control system has been developed using an electric oil pump installed in a simple hybrid vehicle called a mild hybrid. As a result, a smooth feeling starting performance is achieved by operating the system in combination with the engine and other systems.

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.

Most methods of vibration analysis focus on measuring the level of vibration. Some methods like ISO-2631 weigh vibration level based on human sensitivity of location, direction, and frequency. Sound can be similarly measured by sound pressure level in dB. It may also be weighted to human frequency sensitivity such as dBA but sound and noise analysis has progressed to measure sound quality. The characteristic and the nature of the sound is studied; for example equal or near equal sound levels can provide different experiences to the listener. Such is the question for vibration; can vibration quality be assessed just as sound quality is assessed? Early on in our studies, vibration sensory experts found a difference in 4 seats yet no objective measurement of vibration level could reliably confirm the sensory experience. Still these particular experiences correlated to certain verbal descriptors including smoothness/roughness.

This paper presents the results of a study of how people interacted with a production voice-command based interface while driving on public roadways. Tasks included phone contact calling, full address destination entry, and point-of-interest (POI) selection. Baseline driving and driving while engaging in multiple-levels of an auditory-vocal cognitive reference task and manual radio tuning were used as comparison points. Measures included self-reported workload, task performance, physiological arousal, glance behavior, and vehicle control for an analysis sample of 48 participants (gender balanced across ages 21-68). Task analysis and glance measures confirm earlier findings that voice-command interfaces do not always allow the driver to keep their hands on the wheel and eyes on the road, as some assume.