A new deceleration model prior to entry into a curve based on G-Vectoring concept was developed. In this model, the predicted lateral jerk, which will act on the vehicle during cornering, is used to decelerate the vehicle. Using the curvature of the road ahead, lateral jerk can be predicted according to the alteration of this curvature from moment to moment. It is confirmed that the deceleration calculated by this model can imitate the deceleration caused by the driver′s braking. This model will be useful to improve the deceleration feeling of the auto-brake control system prior to entry into a curve.

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We are developing A Survey Simulator to Evaluate Safety Systems (ASSESS) that virtually reproduces a real intersection and traffic flow in which vehicles run autonomously in the computer. In this study, the effect of BAS (Brake Assist System) was evaluated by using ASSESS. We revealed the benefits of BAS in the situations of ordinary driving at the intersection and sudden braking during following driving.

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Present paper describes an approach to the occupants′ energy management during a side crash using ride down effect. A benchmark with stiffness of two folds of conventional structure was theoretically proposed. Based on FEM analysis, a body structure consists of CFRP reinforcement was devised. A dummy simulation with the property of devised structure was done, indicating smaller impact speed to the occupant. Based on the FE analysis, a prototype vehicle was built and CTC experiments were conduced using a special MDB with a mass of 10,000kg. The results of the experiments successfully validated the theoretical study and FEM analysis.

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Our previous research showed that a simple look-ahead model containing single adjustable parameter “look-ahead time” can express not only bat' flight motions but also driver-operated vehicle motions with accuracy. In this research, we propose a new controller for lane-tracking based on the simple look-ahead model and give a theoretical interpretation of the proposed controller. First, we show that the proposed controller is equivalent to a controller composed of two parts: i) feed forward controller using desired course's curvature to reach at 1/3 look ahead time latter, ii) error feedback controller containing proportional gains parameterized by only "look-ahead time". Next, from the stability analysis of close loop system, we clarify how the parameter "look -ahead time" affects the vehicle motion of stability and error between desired course and vehicle trajectories.

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Our previous study reported a look-ahead bio-mimetic controller for lane-keeping based on a bat′s flight model. The look-ahead controller consisted of feedback of look-ahead angle and achieved good tracking even when course curvature changed. However, the look-ahead controller could not achieved good damping. In this paper, we propose a look-ahead controller added feedback of lateral deviation. First, root locus shows that the proposed controller improves damping. Next, numerical simulations show that the proposed controller achieves both good tracking and good damping. Finally, actual vehicle test validates the proposed controller.

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Behavior of a tire for a two-wheeled vehicle and a tire for a four-wheeled vehicle are greatly different. Especially, when we calculate behavior of a two-wheeled vehicle, it is necessary to consider Twisting Moment that acts on an axis normal to ground because influence of the moment on vehicle behavior is too large to ignore. In this paper, we describe the mechanism that the moment is caused and influence of the moment on vehicle behavior.

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In Japan, there are comparatively a lot of people who ride a motorcycle as a hobby. However, the motorcycle has a big possibility as a commuter vehicle because its utilization efficiency of energy is comparatively high, and it is compact. To make the motorcycle convenient for everyone, and to expand use of the motorcycle, we started the development of the device which controls posture of a motorcycle.

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We have described the device which can control the posture of a motorcycle in past two reports, and predicted some effects of the device. In this regard, there was a possibility that the device worsened maneuverability. In this paper as the third report, we describe the control method which can solve the problem, and evaluate some effects of the device.

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In this study, an influence of vehicle styling impression on loudness of acceleration sound was investigated. Luxury or sporty vehicle images were presented to the subjects as the acceleration sounds were being replayed to investigate the influence. The results indicated that the subjects who drove vehicles frequently felt that the acceleration sound presented with the luxury vehicle image was louder than that with sporty vehicle image. But the loudness did not change largely in rarely driving subjects. Consequently, it was clarified that the subjective loudness changed depending on the vehicle styling and the driving frequency of the subject.

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One of the major sources of unburned hydrocarbons (HC) from internal combustion engines is the existence of a space surrounded in the piston top land, top ring, and cylinder wall. This space is called a piston ring crevice. In this paper, the mathematical model on the flow in the piston ring crevice is described. It makes a piston ring crevice a one-dimensional model and it computes. It considers an unsteady flow and it considers the compressibility of gas in the crevice. By grasping the flow of detailed gas in the piston ring crevice when considering an unsteady flow, it clarifies by what phenomenon an exit velocity from the crevice is dominated.

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Internal combustion engines still play a vital role in realizing the low carbon society. For spark ignition engines, further improvement in thermal efficiency can be achieved by increasing both compression and specific heat ratios. In the current work, the authors developed practical technologies to prevent output power loss due to knocking at full load, which is a critical issue for increasing compression ratio. The results show that a significant increase in compression ratio and improvement in thermal efficiency at part load are achieved by using these new technologies.

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A purpose of this study is to develop simultaneous measurement of temperature and velocity in-cylinder. In this report, we tried to measure wall temperature distribution using phosphorescence life time method with high speed camera. Its object was confirmation of possibility of this method for adaptation in in-cylinder measurement. And then we tried to measure gas temperature and velocity, simultaneously. As a result, we measured wall temperature distribution and its temperature had good correlation with a change of calculated gas temperature from in-cylinder pressure. We also measured gas temperature and velocity at motoring condition. Its temperature was good correlation with change of calculated temperature.

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2-D phase doppler technique was used for the measurements of the velocity, size, and flight direction of droplets in diesel sprays. The diameter of the nozzle orifice was 0.113mm. The rail pressure was set at 40MPa by using a common rail system. Measurement position was located at 40mm from the nozzle exit. A part of droplets near the spray center had the radial velocity component to the spray periphery. On the contrary, a part of droplets in the periphery region had the radial velocity component to the spray center. It is understood that combination of these two radial transfers of droplets develops vortices in the periphery region. It is shown that these two radial transfers occurred alternately.

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Multiple-injection models for double-pilot, after and post injections were newly implemented in a previously proposed 0-dimensional cycle simulation code. Furthermore, a model for the sac pressure of a fuel injector was newly developed to predict spray characteristics such as atomization and penetration more accurately even with a small quantity of pilot fuel injection. This paper demonstrates that combustion characteristics such as heat release rate and combustion noise can be reasonably reproduced by these models under various conditions with different injection timings, fuel quantities, and injection pressures.

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Heat transfer coefficients were obtained from measured instantaneous surface temperature and heat flux on all the combustion chamber walls of a direct injection diesel engine. When heat transfer coefficients based on the experiment were compared with those calculated from Eichelberg′s and Woschni′s formulas, it was clearly shown that rates of temporal change were considerably different in some portions. In this paper, causes of the difference are discussed so that insights useful for proposal of a more widely applicable formula with higher accuracy can be obtained.

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A modeling study has been performed for several kinds of dual-component fuel spray. A source code of SUPERTRAPP developed by NIST has been incorporated into KIVA3V to predict physical fuel properties and vapor-liquid equilibrium. A multistep kinetics Shell ignition model and a global single-step mechanism have been employed to account for low temperature and high temperature oxidation reactions, respectively. The calculated results were in good agreement with experimental ones obtained in a constant volume vessel for wide variety of fuel compositions. Using this model, additional investigation was performed to examine a feasibility of combustion control strategy by means of batch-distillation vaporization process of dual-component fuel.

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Pedestrian recognition is one of the key technologies for driving assistance systems. This paper proposes a pedestrian recognition system using a high-definition LIDAR and a vision sensor to achieve high performance in various conditions. Pedestrian candidates are extracted from two sensors in parallel by the SVM-based classifiers. In particular, the region-of-interests in the image processing is set by information about objects derived from LIDAR to reduce false positives as well as computational burden. All candidates are integrated by their likelihood calculated from their classification scores. A quantitative evaluation in a road environment confirms the effectiveness of the proposed system.

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This study examines a teleoperating assist system to prevent the Unmanned Ground Vehicle from unstable condition and accident. A driving assist system for remotely driven Unmanned Ground Vehicle through a display monitor is an effective way to teleoperate. A turning limit trajectory and a predicted trajectory are indicated on the display to assist the driver. Simulation results obtained by the driving simulator showed that the proposed assist system improves stability of Unmanned Ground Vehicle.

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While in-vehicle devices can provide much information in recent years, the workload to select information is increasing. In the first report of this study, useful information for drivers was extracted form the conversation between a driver and a navigator for the purpose of developing a method to provide useful information without increasing the workload. In this report, the concrete rules using the important factors (road environment, a driving skill, timing, and so on) to control benefit of the information were composed.

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This paper described that it applied to off-road engine by metal LS (Longitudinal Structure design) substrate which improves emission conversion efficiency in catalytic converter. From hydrodynamic and heat transfer of viewpoint, metal LS substrate was calculated for optimization of off-road application, at first. Then, the assumption result was evaluated by gas rig and actual engine tests for HC conversion efficiency and catalytic converter volume reduction (=PGM reduction) due to the cost and limitation space. As the result of these investigations for off-road engine application, it confirmed LS substrate advantages compared to conventional substrates in catalytic converter.

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We have developed a new three-cylinder engine “R06A” that has installed to our new K car launched in January, 2011. Improvement of fuel economy is the top priority of this engine development. In order to satisfy engine performance, we improved overall thermal efficiency, mainly by combustion improvement, pumping loss reduction and friction reduction. The new K car installed with this engine achieved the lowest fuel consumption in the domestic market, 24.2km/L in JC08 drive cycle with a start-stop system. Also, the developed engine provides far lower noise level than current engines while achieving the lightest-weight in 660cc class.

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New power plant like clean diesel engine, hybrid, and supercharged petrol engine requires additional heat exchangers in front end of the vehicles. By this, power of cooling system is increased, and improvement of fuel consumption by new power sources is reduced. In new technology “SLIM”, operation of one heat exchanger is changeable by various driving conditions. Heat load of a condenser of AC system and that of an additional heat exchanger like CAC or sub-radiator for diesel engine or hybrid vehicles are changeable by vehicle speed or engine load. Using this conception, heat exchangers of front end of a vehicle is made compact by 30% and more.

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In the communication systems field to exchange position information such as vehicle to vehicle communication, the position data based on GPS are very important. However GPS data have dispersion under multipath environments, so various methods have tried to compensate GPS data. In this paper, we propose a terminal position estimation method by checking a prospected position and transmitted position, and evaluate a network quality using mutual diagnostic network which is made by evaluating each connected terminals (vehicles and pedestrians).

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The processing technology in the honeycomb made of CFRP core and the electric discharge machining of wire cutting technology of the sandwich made of CFRP panel were developed aiming at the production of the monocoque frame with the CFRP sandwich panel in the electric vehicle and the hybrid-power car. It was developed that as the production of the CFRP honeycomb core made of the silicone rubber molding (SR method) and foam material insert construction molding (FMI method). In case of the condition that carbon fiber is contained 60% or more it, CFRP was able to be cut by electric discharge machining. The speed of cutting electric discharge machining of CFRP was about 1/3 of the aluminums. The sandwich made of CFRP panel was able to be cut by electric discharge machining of the wire cutting.

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