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In hot climate regions, there is demand for improved thermal comfort for rear occupants in vehicles not equipped with a rear air conditioner. One solution to this challenge is a circulator mounted on the ceiling. The circulator is a product designed to enhance thermal comfort for occupants by circulating the air in the cabin. The conventional circulator design, which employs a cross flow fan with a large cross section, juts into the cabin space, because it is difficult to package. Consequently, the challenge for the circulator is to provide thermal comfort for rear occupants while taking up the minimum cabin space under the ceiling. To solve this challenge, that is, to enable a substantially thinner structure, while retaining the same level of air flow delivered as before for the same thermal comfort as the conventional circulator, we divided the structure into an air outlet and an air blower.

As a method of maintaining thermal sensation and comfort inside a passenger compartment, not only a conventional HVAC system but also a combination of a HVAC system and other devices such as seat heaters, a steering wheel heater, ventilation seats are increasing. This research developed a method to evaluate thermal sensation of a human body when using these various thermal control devices. This method can evaluate the heat balance of the human body by calculating the amount of heat exchange between a human body and the external environment, and it takes into consideration the influence of heat exchange by heat conduction with seats or a steering wheel. The human thermal model is made by dividing a human body into various segments, and it is the model that considers heat transport by blood flow for each segment.

Head-up displays (HUDs) give visual information to drivers in an easy to understand manner and prevent traffic accidents. Augmented reality head-up displays (AR-HUDs) display the driving information overlaid on the actual scenery. The AR-HUD must allow the visual information and the actual scene to be viewed at the same time, and a sense of depth and distance are key factors in achieving this. Binocular parallax used in stereoscopic 3D display is one of the most useful methods of providing a sense of depth and distance. Generally, stereoscopic 3D displays must limit the image range to within Panum’s fusional area to ensure fusion of the stereoscopic images. However, when using a stereoscopic 3D display for an AR-HUD, the image range must extend beyond Panum’s fusional area to allow the visual information and the actual scene to be displayed at the same time.

Driving is an action that depends strongly on visual information. For displays in the cockpit, a combination of “ease of viewing” to inform the driver of danger early and “annoyance reduction” to avoid drops in the driver’s perception is needed. In this study, we tried to capture “ease of viewing” and “annoyance” in one fixed-quantity indicator. We took up a Camera Monitor System (CMS) as the subject and analyzed the effect that annoyance with the display used in CMSs has on driving behavior. Based on our analysis, we hypothesize that evaluating carelessness in viewing behavior is related evaluating to annoyance. Next, we chose a Detection Response Task (DRT) technique as a method to evaluate driving behavior influenced by this annoyance.

A Rear Cross Traffic Auto Brake (RCTAB) system has been developed that uses radar sensors to detect vehicles approaching from the right or left at the rear of the driver’s vehicle, and then performs braking control if the system judges that a collision may occur. This system predicts the intersecting course of approaching vehicles and uses the calculated time-to-collision (TTC) to control the timing of automatic braking with the aim of helping prevent unnecessary operation while ensuring system performance.

The electric power steering (EPS) is increasing its number since there are many advantages compared to hydraulic power steering. The EPS saves fuel and eliminates hydraulic fluid. Also, it is more suitable to the cooperation control with the other vehicle components. The EPS is now expanding to the heavier vehicle with the advance in the power electronics. In order to meet customer's needs, such as down-sizing, lower failure rate and lower price, we have developed the new motor control unit (MCU) for the EPS. The motor and the electric control unit (ECU) were integrated for the better installation. We adopted new technologies of redundant 2-drive design for more safe EPS. “2-drive Motor Control technology” which consists of dual winding, two torque sensors and two inverter drive units. In our developed MCU, even if there is a failure in one of the drive unit, the assistance of the EPS can be maintained with the other drive unit.

In automobiles, Integrated Starter Generators (ISGs) are important components since they ensure significant fuel economy improvements. With motors that operate at high voltage such as ISGs, it is important to accurately know partial discharge inception voltages (PDIVs) for the assured insulation reliability of the motors. However, the PDIVs vary due to various factors including the environment (temperature, atmospheric pressure and humidity), materials (water absorption and degradation) and voltage waveforms. Consequently, it is not easy either empirically or analytically to ascertain the PDIVs in a complex environment (involving, for example, high temperature, low atmospheric pressure and high humidity) in which many factors vary simultaneously, as with invehicle environments. As a well-known method, PDIVs can be analyzed in terms of two voltage values, which are the breakdown voltage of the air (called “Paschen curve”) and the shared voltage of the air layer.

This paper presents detection technology for a driver monitoring system using JINS MEME, an eyewear-type wearable device. Serious accidents caused by human error such as dozing while driving or inattentive driving have been increasing recently in Japan. JINS MEME is expected to contribute to reducing the number of traffic deaths by constantly monitoring the driver with an ocular potential sensor. This paper also explains how a driver’s drowsiness level can be estimated from information on their blink rate, which can be calculated from the ocular potential.

Humidity sensors used in automatic windshield defogging controls contribute to the improvement of fuel consumption. The optimum control of air conditioning systems can be realized by adding humidity information to conventional systems which have used only temperature information. While resistive humidity sensors have been widely used, their sensing range and responsiveness are observed as issues. Resistive sensors cannot function at a humidity range of around 100% RH as well as at a low temperature range, and have a low response rate to sudden changes in humidity. It is considered that resistive humidity sensors will be replaced with capacitive ones which have a wide sensing range and high responsiveness.

The number of idle-stop vehicles is rapidly increasing in recent years, and air-conditioning technologies that extend engine stopped time while maintaining the cabin comfort are required. When the engine stops during idle- stop mode, the air conditioner also stops functioning. To maintain cabin comfort, the engine is restarted to work the air-conditioning cycle, which reduces the fuel saving effects. As a countermeasure, a cold storage air conditioning system has been proposed. The system extends engine non-operation time by using cold storage for generating cool air while the engine is stopped. We have integrated this technology into an evaporator, which is used in the air-conditioning cycle, and the system has a short cold storage period and a necessary cold release period. This report describes its concept and effects.

Deceleration patterns of an expert driver will be formulated using the perceptual risk index for approach and proximity of a preceding vehicle as an example of comfortable braking pattern. It will be shown that the formulated braking pattern can generate smooth deceleration profile uniformly for many conditions of approaching conditions. In addition, brake initiation timing of expert driver will be successfully formulated using the alternative index. Finally, an automatic braking system will be proposed based on the formulated brake initiation model and the velocity profile. Twenty five expert drivers experienced the automatic braking installed in an experimental car. It will be shown that the proposed system can generate smooth profile and realize secure brake patterns based on subjective evaluation.

Measurements of residual stress in a printed circuit board, which consists of copper foil, silver alloy and thermo plastic resin, were conducted under a thermal cycle. The printed circuit board was given a ten-layer repeat of prepreg and made by thermocompression bonding. Experiments suggested the possibility of measuring surface residual stress of copper circuits and the internal residual stress of metallic connections by synchrotron radiation of Spring-8. FEM analysis of the printed circuit board during a thermal cycle was conducted, and the result was adjusted to X-ray stress using absorption correction. X-ray stress during a heat-cycle obtained by synchrotron radiation showed good agreement with stress calculated by FEM analysis.

Stringent emission regulations call for advanced catalyst substrates with thinner walls and higher cell density. However, substrates with higher cell density increase backpressure, thinner cell wall substrates have lower mechanical characteristics. Therefore we will focus on cell configurations that will show a positive effect on backpressure and emission performance. We found that hexagonal cells have a greater effect on emission and backpressure performance versus square or round cell configurations. This paper will describe in detail the advantage of hexagonal cell configuration versus round or square configurations with respect to the following features: 1 High Oxygen Storage Capacity (OSC) performance due to uniformity of the catalyst coating layer 2 Low backpressure due to the large hydraulic diameter of the catalyst cell 3 Quick light off characteristics due to efficient heat transfer and low thermal mass

PBT (polybutylene terephthalate) and epoxy adhesive, which both have superior heat resistance and environmental resistance, are a representative combination now being applied to many parts. Generally, PBT is annealed after molding at a temperature above the glass transition temperature to ensure dimensional stability when in use. But in this case, this process decreases the adhesive strength between PBT and epoxy. This study analyzes the adhesion degradation mechanism in this system and a countermeasure technology is proposed. Regarding this PBT-epoxy adhesion degradation mechanism, focus is placed on changes in the fracture surface, which is analyzed before and after annealing. From this analysis it becomes clear that generation of a WBL (weak boundary layer) is caused by non-crystallization and a migration of the PBT functional group on the adhesion surface layer.