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Combustion variation is widely known as a factor that prevents engines from achieving high efficiency. In this study, a model to predict IMEP per cycle is constructed by machine learning. Furthermore, we propose a control method for cycle-to-cycle combustion variation using the model. The effectiveness and performance of the proposed method are experimentally validated on a spark-ignited gasoline engine test bench. From the experimental results, IMEP per cycle was not successfully controlled. This may be due to the low prediction accuracy of the model and the use of what is considered to be the highest efficiency for comparison.

In order to improve the ignition stability and reduce the cycle-to-cycle variation, it is necessary to understand the mechanism of the flame kernel development and the local quenching effect during the spark ignition process. In this study, experiments for the spark ignition process in a high-speed lean gasoline-air mixture turbulent flow field were conducted. OH* chemiluminescence measurement and focusing Schlieren photography was applied to observe the development of flame kernel and discharge channel behaviors simultaneously. Results indicated that flame kernel fragments, generated by the restrike and short- circuit of discharge channels, quenched due to the local turbulence, which led to slow flame propagation or misfire. In that cases, the initial flame kernels showed stretched behaviors, along with high curvatures.

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.

This paper deals with a combustion control system design problem for premixed diesel engines. Premixed diesel combustions can achieve high thermal efficiency while reducing emissions. However, premixed diesel combustions have low robustness with respect to changes in the environment. The traditional engine control is the feedforward control using look-up table called control map. Therefore, it is difficult to maintain a stable combustion for the premixed diesel combustions. Moreover, making the control map requires a huge number of experiments. In this paper, in order to robustly realize the premixed diesel combustion, a passivity-based adaptive output feedback control system design scheme is proposed based on a discrete dynamics model of the diesel combustion. The proposed method controls the in-cylinder heat release rate at each combustion cycle.

In this paper, an online automatic adaptation method for model-based control of a diesel engine is developed. Control-oriented models based on physics has been proposed as substitutes for conventional control methods to improve the performance of engine under real driving situation. Even such physical-rich models have fitting parameters and it is preferable to adapt the parameters according to the real-time operating condition. Therefore, an automatic adaptation method for the model is developed, and the method is based on neural network. The prediction accuracy of the model is evaluated by simulation and it is confirmed that the method can be applied online to a real engine by experiment.

Vehicle lateral states such as lateral distance at a preview point and heading angle are indispensable for lane keeping control systems, and such states are normally estimated by fusing signals from an onboard vision system and inertial sensors. However, the sampling rates and measurement delays are different between the two kinds of sensing devices. Most of the conventional methods simply neglect measurement delay and reduce sampling rate of the estimator to adapt to the slow sensors/devices. However, the estimation accuracy is deteriorated, especially considering the delay of visual signals may not be constant. In case of electric vehicles, the actuators for steering and traction are motors that have high control frequency. Therefore, the frequency of vehicle state feedback may not match the control frequency if the estimator is infrequently updated. In this paper, a multi-rate estimation algorithm based on Kalman filter is proposed to provide lateral states with high frequency.

There are such outside door handles called smart handles which have a transmitting antenna, a lock/unlock sensor, and a sensor detection circuit, with which operation of door lock is possible just by "touching" the electrostatic-capacitance type sensor of the handles.As the design of the outside handles, body color painting and Cr plating are adopted. However, if plating is applied over the entire surface of a smart handle, electromagnetic waves transmitted from the antenna will be blocked since plating material is electrically conductive. In addition to this, touching a part other than the sensor may change the electrostatic-capacitance of the sensor, which results in unwanted functioning of the lock/unlock sensor. Because of this, only part of the handle, which does not hinder the transmission of electromagnetic waves and does not cause unwanted functioning, is covered by plating, that is called, "Partially plated specifications" (Figure 1).

In this paper, we report the design, fabrication, and performance evaluation of MEMS wireless temperature sensor, which can be applied to the wall temperature measurement in combustors. The sensor is composed of a LCR resonant circuit and its coil is inductively coupled with an external read-out coil for the wireless sensing. Electrical resistance change of the coil due to the temperature change is used to measure the wall temperature. A prototype sensor is fabricated with MEMS technologies and its performance is evaluated in the temperature range of 25 - 200 °C. The measured sensitivity is found to be 2.5 °C at 177 °C, when the distance between the sensor and the readout coil is 1.77 mm.

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.

The complexity of drivetrain system design lies in the need for diligent consideration of individual component specifications, their effect on various performance aspects of the overall system, as well as any performance trade-offs that may further add to the complexity of system design. This paper describes a design methodology developed by capturing best practices for conducting design architecture analysis in full account of key design components critical to ensuring efficient and effective development of drivetrain systems. This methodology is derived from the architecture analysis based on core competencies and architecture strategy, the veteran's way of practical selection of design items and determining the sequence of the study process.

In this paper, the range extension control system based on least square method is proposed for electric vehicles with in-wheel motors and front active steering. This proposed method distributes front and rear wheel side-slip angles and driving force difference between left and right motors from lateral force and yaw-moment. The proposed method enables to reduce driving resistance generated from front steering angle. In fact, the mileage per charge is extended up to 200 m/kWh. Simulations and experiments are carried out to confirm the effectiveness of the proposed method.

Clutch judder phenomenon is known as a vehicle vibration caused by the drive torque fluctuation from the clutch unit at takeoff. In this paper, a novel strategy for improving clutch judder phenomenon caused by the movement/tolerance between mechanical parts comprising the clutch system is introduced. In order to simulate the movements of the clutch system and of the vehicle drivelines precisely, we used numerical analysis software and have achieved high-grade prediction of the clutch torque fluctuation and the vehicle vibration. Using this method, we have developed a high-quality clutch system that enables smoother clutch engagement, and at the same time, development efficiency has been improved.

An experimental study was carried out on visualization of liquid phase temperature distributions in high-pressure diesel sprays impinging on a heated wall. Naphthalene/TMPD-exciplex fluorescence method and pyrene-excimer fluorescence method were utilized for the thermometry. The sprays were injected into a high-pressure and high-temperature gaseous environment. The nozzle hole diameter was 0.100 mm or 0.139 mm. The results showed that cool pockets were formed at the tip and in the impinging part of the sprays. The spray for the nozzle with 0.100 mm hole was heated up faster near the nozzle than for the nozzle with 0.139 mm hole.

Biomass is one of the attractive alternative fuels, which exists dispersively. Small size gas engine power generation with gasification biomass gas is one of the efficient methods. However, since its calorific value is lower and its composition can be affected by gasifying conditions, it is difficult to stabilize and achieve high thermal efficiency engine operation. This study aims to develop a small size gas engine system with biomass gas by modifying the control system of a conventional spark ignition engine. In this paper, effect of fuel composition on combustion was clarified experimentally to get guideline for the engine control system.

We have developed a Hall effect device based height sensor of a smaller size, and with higher temperature operation durability, as compared to conventional devices. Downsizing of the sensor is realized by decreasing a number of parts, and by employing a short bearing. Improvement in heat resistance is achieved by adopting an IC with sufficient heat resistance and a SmCo magnet with high coercive force. In addition, a sensor of a high degree of accuracy is accomplished by improvements in linearity and robustness of magnetic characteristics. Development of a small, heat-resistant and accurate height sensor will promote the spread of systems using a height sensor, such as a High Intensity Discharge (HID) headlamp.

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).

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.

We have developed Sensor-less Memory Seat system that requires no position sensors such as Hall ICs etc.. It detects the rotation of DC motor by current ripple signals in motor operating current. The developed Sensor-less position control system can attenuate a wide frequency variation of Motor current noise which varies depending on motor condition and convert small current ripples to Pulse signals in proportion to the rotation of DC motor. We realized low cost position control method for use in Memory Seat system.

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.