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This active-drive wheel speed sensor, developed by the high-frequency magnetic system, enables detection of very slow wheel speeds - hitherto difficult to accomplish with any conventional type of Magnetic Pick up - by applying the eddy current effect through the high-frequency magnetic field. The following report presents an analysis of the magnetic circuit which integrates the magnetic-field generating coil with the detection rotor, and the unique circuit system which ensures strength against eccentricity of the wheel rotor and air gap variations, etc.

Recently, automobile features designed to improve maneuverability and convenience are being improved. However, many drivers still have difficulty with parking maneuvers. Although parking is unavoidable for drivers, yet ranks third among the most difficult driving situations for Japanese drivers. Drivers in other countries also consider parking to be difficult and even skill drivers would appreciate some assistance. Therefore, a parking support system has been developed to reduce the workload for all drivers while also improving parking performance. The parking support system Human-Machine Interface (HMI) operation should be designed to easy to use for best performance. The back-in perpendicular parking performance of drivers with different skill levels was studied to see the effect of the parking support system. Back-in perpendicular parking is the major parking method in Japan.

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.

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 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.

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.

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 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.

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.

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.

To develop Low-cost system, we used matrix function under the condition of the vehicle having symmetrical brake conduit and four-wheel control capability. As a result, 3 SOL system is a likely candidate for rear-wheel drive vehicles, and a 4 SOL system for front wheel drive vehicles by using a orifices instead of the Normal-Open solenoid. In developing a logic system, we used the learning control function with a duty pointer containing four hydraulic wave modes. The actuator weighs 2.2kg and has a volume of 1.2 liters (W90 × H105 × L133)

We have developed an electric rear-drive unit to enable all-wheel drive (AWD) applications to the compact FF hybrid passenger vehicles. The development is intended to provide a compact and low cost unit with low fuel consumption. The unit newly introduces a two-axis gear train that enables a compact design, an induction motor and an ATF (automatic transmission fluid) stirring resistance restraining structure that contribute to lower fuel consumption. This paper presents the features and performance of the electric rear-drive unit.

We have tried to develop our own integrated CAD/CAE systems, to provide user friendly systems to our staff members who are not familiar with CAE. These systems have been shown to support our R&D in more efficient ways than before. - They improved the quality and reduced the time of experiments and tests. The concept of development and several examples will be reported.

In a system with which acceleration and braking by the driver are automated, a gap against the system can be felt when the timing of acceleration or deceleration is different from that intended by the driver or the extent of acceleration or deceleration exceeds an acceptable limit. For an automated system, it is important to realize a control that provides comfort and a sense of security for the driver. This paper is related to the technology that secures the ride comfort felt by the driver (comfort and a sense of security) within an appropriate range and presents a discussion of the technological means to improve the ride comfort from a viewpoint particularly related to longitudinal direction.

Development of a system which utilizes technology for the recognition of a vehicle's surroundings. Research is currently taking place in many countries, the goals of which are to improve a vehicle's safety and convenience by reducing driver strain through the automation of the recognition, judgment, and operation capabilities that are needed when driving an automobile. To recognize the vehicle's surroundings, we have adopted an image sensor system which offers superior three-dimensional recognition capabilities. In this paper, we will introduce a inter vehicle distance control system which controls the vehicle's throttle and braking functions by detecting the position of the driving lane and the distance to the vehicle in front based on the images obtained by a CCD camera.

With the improved safety performance of vehicles, the number of accidents has been decreasing. However, accidents due to driver distraction still occur, which means that there is a high need to determine whether a driver is properly looking at the surroundings. Meanwhile, with the trend toward partial automatic driving of vehicles in recent years, it is also urgently required that the state of the driver be grasped. Even if automatic driving is not installed, it is desired that the state of the driver be grasped and an application for control be performed depending on the state of the driver. Under these circumstances, we have built an algorithm that determines of the direction a driver is looking, to make a basic determination of whether or not the driver is in a state suitable for safe driving of the vehicle.