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By developing a mechanical-firing sensor using rotational inertia effect, we have completed miniaturization of the sensor and have developed a new-type mechanical-firing airbag system. This airbag system has been confirmed to have superior occupant protection performance after conducting a variety of vehicle crash tests and sled tests.

Introduction of occupant classification system which has load sensor with a strain gauge built into the seat structure, and identifies occupant's physique by measuring weight on seat, and meets the United States FMVSS requirements (new FMVSS208 Requirement).

If a crash prediction system (Rear pre-crash safety) determines that a rear crash is unavoidable, this product reduces whiplash injury by reducing shock to the neck by quickly moving the front part of a head restraint forward thus shortening the distance between the head and the head restraint. Pre-crash intelligent head restraint systems were developed for safe vehicle. In this paper, the method to detect collision risk and how to protect passenger's heads was introduced. Also sensor idea and operating mechanism were explained.

As a process that enables the high-speed and continuous forming of lengthy materials with a constant cross-sectional configuration, roll forming offers much higher productivity than the stamping process. However, in case a change must be made to the shape of the cross section, the material must normally be stamped or joined with a part containing a separate shape. This affects productivity, increases the number of pieces, and degrades the material's appearance. This report describes the roll-forming technology that we developed, in which the cross section of the material can be changed gradually. This method adopts a system which uses a movable and rotatable roll-stand that enables high-speed, continuous roll-forming processes.

It is well known that the self-aligning torque decreases before lateral force is saturated. Focusing on this self-aligning torque change, an estimation method has been developed to detect the friction condition between steered wheels and road surface before the lateral force reaches the friction limit. The lateral grip margin (LGM) is defined based on the self-aligning torque change, which is obtained using the EPS torque and motor current information. The LGM is theoretically analyzed based on the tire model and experimentally verified through the full-scale vehicle test. Moreover, the estimated LGM is applied for the chassis control systems to improve the vehicle dynamics performance.

Chassis control systems, including ABS, traction control and vehicle stability control, utilize the available tire forces to improve vehicle acceleration, deceleration, handling and stability for active safety. Thus, it can be very beneficial to evaluate the tire force characteristics on actual road surfaces and use this information in the chassis control systems. In this paper, the research activities on evaluating the tire force characteristics and the performance of chassis control systems are introduced. The test procedure described for measuring the tire force characteristics on actual road surfaces using a test vehicle is relatively easy. The brake and side force characteristics are shown from the experimental data. The tire force characteristics during ABS braking were measured on various road surfaces. ABS performance is discussed based on the measured tire force characteristics.

In recent years, the number of reported traffic accidents due to sudden deterioration in driver’s physical condition has been increasing, it is expected to develop a system that prevents accidents even if physical condition suddenly changes while driving, or reduces damage through vehicle body control. For this purpose, it is necessary to detect sudden changes of the driver’s physical condition, and research is being conducted widely. Among them, it is reported that some of such changes may appear in the heartbeat interval. In other words, by acquiring the driver’s heartbeat interval in real time, it may be possible to detect the sudden changes, and reduce traffic accident. Even if a traffic accident occurs, the damage can be reduced by emergency evacuation immediately after detecting sudden changes.

In this paper, we discuss vehicle directional stability and introduce advanced stability control (ASTC) to stabilize the vehicle during severe cornering. Vehicle behavior in a transient steering condition during severe cornering was analyzed by computer simulation. It was found that applying an external yaw moment makes the vehicle more stable. The effect of controlling the brake force response is also evaluated by simulation to determine the brake actuator response criteria. The actual vehicle test was performed with a pylon slalom using a hydraulic brake actuator. It is verified that the ASTC stabilizes the vehicle for transient steering maneuvers.

In order to cope with the increases of the consciousness of safety driving and the aged drivers, AISIN SEIKI CO., LTD. and TOYOTA MOTOR CORPORATION have aimed at improvements in rear view visibility of outside mirrors running under the raining conditions (water cleaning), and have developed mirror with water cleaning device utilizing ultra sonic vibrations. The mirror was named as ULTRA SONIC VIBRATING MIRROR and have been installed with a TOYOTA flagship car “CELSIOR” corresponding to “LEXUS” sold in the U.S.

Our society is faced with the serious problems such as aging population growth, environmental pollution and limited energy resource issues. As a means to address these issues, we are developing new mobility vehicles designed to support short-distance trips in urban settings. These mobility vehicles are intended for use in pedestrian areas inside buildings as well as outside, including public roads. In order to ensure safe and convenient operation for both pedestrians and mobility users, we conducted a risk assessment of mobility vehicles in pedestrian areas, and then developed a feature to autonomously limit the speed according to their surrounding conditions. This report discusses the utility of these mobility vehicles with the safety functions based on the fully conducted risk assessment, collision test and performance evaluation in public roads.

This paper reports the results of a study into a preview control that uses the displacement of the road surface in front of the vehicle to improve for front and rear actuator responsiveness delays, as well as delays due to calculation, communication, and the like. This study also examined the effect of a preview control using the eActive3 electric active suspension system, which is capable of controlling the roll, pitch, and warp modes of vehicle motion.

A newly developed parking assist system, which is based on rear view camera, is disclosed. System features include ‘parallel parking aid’ with voice guidance message along with several guidelines superimposed onto the rear view camera image. Voice guide message helps driver understand appropriate timing for each procedure of parallel parking. The system was designed to let driver follow the system by voice message rather than visual guide information through the screen for safety reason. The guide algorism is designed under ‘two turns’ parking maneuvers so that required longitudinal parking space becomes minimal. A key development of this system, which is to design the guide algorism to avoid collision to adjacent vehicle during parallel parking operation, is also discussed in this paper. User can select either ‘parallel guide’ or ‘normal (such as garage parking)’ mode through touch screen switch on display surface.

This paper describes the investigation into the contact pressure and incidental deformation on the contact surface of the piston skirt which comes in contact with the cylinder bore in operation. Focused on the single piston static tests in the first place, relationship between the contact pressure on said skirt and the strains developed inside the skirt, and the relationship between the deformation of skirt face and the strains inside the skirt were studied. Then, the dynamic contact pressure onto the skirt in operation and the amount of deformation were calculated based on the relationships mentioned above using the factor of dynamic strains measured on an engine in operation. The deformation of skirt calculated using said dynamic strains was verified by the direct measurement of the skirt deformation. It was demonstrated that the thrust side of a piston skirt was largely deformed due to enlarged contact pressure caused by the piston slap subsequent to firing top dead center.

As automotive electronic systems advance, the wire harness is the mainstream for necessary wiring in resin-made motor-driven actuators with wire connection labor and purchased-parts accounting for the majority of costs. As a means to eliminating the harness, there is a method of forming the conductive material on the inside, but this method leads to cost increases when there is a comparatively large number of wires because the required die insertion time becomes longer and automatic insertion equipment becomes necessary. The following paper reports on an integrated high-speed process that combines stamping and injection molding into a single process.