Some ultrasonic friction motors uses resonance frequency of two modes to generate ellipse motion on contact point. However there are no detail reports about degree of freedom or constraints on design or tuning of frequency when resonance frequencies in two directions are used. The paper investigates experimentally what phenomena occur when two modes resonance frequency of a vibration mechanism are matched and the mechanism is excited in two directions simultaneously. An experimental vibration mechanism which has the same structure in two orthogonal directions are manufactured and driven under some different driving conditions! e.g. frequency, amplitude or phase of sinusoidal excitation. Then some interesting results such as every driving condition gives influence on resulting vibration status are obtained.

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This paper aims to develop a prototype visual-aid system to identifying ahead of preceding vehicles. Assuming a three-vehicle car-following, the system is to simply transfer the front view of the second vehicle that recorded via a wireless video camera to the third vehicle on-board monitor. The driver of the third vehicle is expected to drive with the visual aid of two more preceding vehicles. The data recorders installed on both second and third vehicles measured car-following data such as lateral acceleration rate and speed. Field data collection on a test track of driving school showed that the system properly works without significant delay and that the vehicle reaction time and maximum deceleration rate have no significant difference with and without the visual aid.

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The optimum velocity model is well-known by the fact that the basic characteristics of traffic flow can be simulated. But many of this model do not reflect the velocity change of the actual vehicles. In this study, the accelerating and decelerating cars in a cluster are recorded by a digital video camera from the high building. Each car's position is acquired by the VideoPoint. The function of the optimal velocity model is defined by this results, and the phase transition of traffic flow in a single-lane is investigated by this model. Especially, we study the propagation of a traffic jam in following vehicles with a sudden deceleration of a lead vehicle by using this model.

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This paper presents identification and application for driving assist system of a decision making model in the driving behavior based on the Logistic regression model. At first, the decision making for the lane change action on the expressway is identified based on the Logistic regression model. Then, it is shown that the identification model is useful for the prediction of the decision making for the lane change action of driver. Finally, we built a decision making model of driver and implemented it in the proposed driving assist system. As a result, we verified the effectiveness of the proposed technique.

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We investigate running stability of the high-speed-moving vehicle subjected to the seismic excitation considering the effect of passengers. The analytical model of the vehicle consists of the body, the trucks and the wheelsets.The passengers are modeled as the spring-mass-damper system. The behaviors of the vehicle and the passengers are simulated with the actual seismic input to the system in horizontal and vertical directions. Then the possibility of the rollover of the vehicle is evaluated. We focus on the effect of the mass balance of the passengers on the vehicle behavior and the damping characteristic of the human when the vehicle is subjected to the amplitude excitation.

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This study examines the braking assistance system for train drivers when stopping at a station. The assistance system informs a driver of a predicted stopping position calculated by vehicle velocity and deceleration. Trains-driving simulator experiments are examined with several subjects who are required train driving with mental calculation assumed mental workload. Subjects with the assistance system can operate brake handle smoothly, while subjects without the assistance system repeat modified braking operations.

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The sprinkler snow-melting equipment is operated by local inhabitants whom local public entity entrusted. There is a difference in an operating experience and the knowledge of the equipment for entrusted operators. In addition, the entrusted operators can do only the change of the ON and OFF of the water pump. They cannot operate water temperature and quantity of sprinkling. In this study, an operating support system by the neural network which learned the judgment of the expert operator and the knowledge of the road with sprinkler snow-melting equipment, was developed.

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Kashiwa city was adopted as one of four ITS FOT model cities in Japan in June 2009. The Kashiwa ITS council composed of six working groups has been founded in February 2010 to efficiently promote corresponding GIA activities. The outline of ITS FOT plan in Kashiwanoha district by the Kashiwa city and the outline of activity targets by the ITS council are described.

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This paper aims to analyze usual driving data of elderly drivers and non-elderly drivers by using continuous sensing driver recorder. Elderly driver collective consists of drivers aged 65 and over, while non-elderly driver collective consists of those aged below. Individual driving database is created from their collected driving data. Then, the driving data of each collective are compared to find some feature of elderly drivers' driving behavior. The result shows that the elderly drivers tend to drive at 30-50km/h more frequently than the non-elderly drivers and they prefer gentle acceleration and deceleration.

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The paper studied correlation between lateral acceleration and electromyogram (EMG) of sternocleidomastoid (SCM) muscles, which is to clarify the possibility of EMG as an indicator of physical load against head rolling. SCM muscles are in both sides of neck, and play important parts in lateral stability of head. The experiment is a lateral sine wave vibration testing using a driving simulator. The subject sits in the passenger seat, and EMG of SCM muscles and accelerations of the head and shoulder are measured. Three settings of amplitude and frequency are designed for the vibration testing. The result indicates a tendency that root mean square (RMS) values of EMG increase following the increment of amplitude of vibration. EMG of SCM muscles becomes maximum value at frequency of 1.5 Hz, which results in resonance of lateral head vibrations.

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The realization of the autonomous vehicle has many advantages such as decrease traffic accident and so on. A vehicle motion control system is one of the important components in the autonomous driving system and is influences the occupants comfort, but it is not designed in the consideration of occupants. In this study, the evaluation technique of the autonomous vehicle controller based on the driver behavior model by using RRV3 in RRV method is proposed and the effectiveness of the proposed technique for the braking operation is verified. The braking operation experiments with the autonomous controller were carried out, and experimental data ware compared. As a result, when examinees ride the model that is nearer the stop line than own one, RRV3 changes suddenly. The effectiveness of the proposed technique for driving operation was verified.

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Eco-driving is proposed for reduction of vehicle CO_2 discharges, and eco-driving is a driving mode through driver behaviors mainly about accelerator works such as smooth acceleration at start, preservation of the steady speed, and active use of engine brake. In this study, in virtue of a universal driving simulator (DS), driving experiments by subjects were conducted in the modes of normal driving, eco-driving, and eco-driving with eco-indicator. In the experiments, surface electromyography (sEMG) of leg muscles of driver was measured to clarify muscle fatigues in different driving modes, and further driver behaviors were also analyzed. Through comparing analysis results, it is validated that eco-driving with eco-indicator is effective as an eco-assistant-system.

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To reduce amount of CO_2 emission and improve efficiency of commodity distribution, a highway transportation system of automatic platooning is developing by controlling closed trucks distance to reduce their large air resistance. However, driver stress intensity of automatic platooning has to be evaluated, since driver stress may occur by the closed gap distance. In the paper, bio-signal indices of surface electromyogram (sEMG) of masseter and emotional perspiration (EP) of palm are proposed to evaluate driver stress intensity of automatic platooning. In virtue of a universal driving simulator, the bio-signals of subjects were measured in virtual traffic environment of automatic platooning. By the analysis of the bio-signal indices, it is found that driver stress intensities decrease in the order of trucks distances of 4, 8, and 12 meters sequentially, and analytical result shows that the driver stress intensities of trucks distances of 4 and 8 meters in automatic platooning mode are larger than the driver stress intensities of normal driving in normal driving mode. Moreover, relations of the driver stress intensities and inverse Time-To-Collision (iTTC) in automatic platooning modes are also discussed.

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Ride comfort of a seated passenger in the railway vehicle relates to vibration of seating face, therefore vibration evaluation is necessary for improvement of the ride comfort. Some methods using change of seat pressure have been proposed to evaluate vibration of seating face. However, characteristics of seat pressure for the ride comfort evaluation have not been clarified well. Therefore the final purpose of this study is suggestion of the ride comfort evaluation index. In this study, some characteristics of the methods using the seat pressure are clarified. For example, this study clarifies that the evaluation by using seat pressure has to consider the difference of vibration frequency. These are fundamental findings to establish the ride comfort evaluation method by using the seat pressure.

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In recent years, the number of senior citizens is increasing and the number of elderlies who complain of backache and arthralgia also tends to increase. This study attempts to comprehend the dynamic behaviors of a human rising from a chair through stand-up experiments using gyro sensors and force plate, and individual differences in rising motion are considered. In addition, authors develop the 2D analytical model and the equation of motion of a rising human and evaluate joint torque during rising performances by inverse analyses. The experimental results showed that standing-up motion changes depending on the chair height in general, but the motion for a particular subject does not depend on the chair height. Moreover, it is found that individual differences in rising motion are large for taller chairs, but not for lower chairs.

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This study presents the finite element analysis (FEA) on an arch-type piezoelectric film sensor which had previously been designed for unconstrained monitoring cardiorespiratory signals. Both ends of a flexible arch-shaped plastic sheet are fixed on both ends of piezoelectric film, which is shorter than the arc length of the arch-shaped plastic sheet. As a result, the structure behaves as force-conversion mechanism where pressure to perpendicular direction is converted into horizontal tension. The FEA suggested how the ratio of the arc length of the plastic sheet to the length of the piezoelectric film affects the sensitivity.

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It is well known that the vehicle with smaller sideslip angle has better performances than larger one. The authors have analyzed its reason using the different sideslip angle vehicles at driving simulator. It is found that the overshoot at the end of lane change is affected by the sideslip angle .The reason of the overshoot is that the driver adapts the steering angle to the route angle. The best position of yaw- center is located between the center of gravity and rear wheel.

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These days, the new vehicles for the individual usage called Personal Mobility Vehicle (PMV) are developed for our new choices for mobility. For example, the several types of the two-wheeled inverted pendulum vehicle and the small wheel electric bicycle have been developed. In this trend, however, each PMV has not evaluated systematically. Therefore, in this paper, we show the approach to evaluate several PMVs from the multiple aspects: the stability and the maneuverability, the affinity with pedestrians and the practicality in society.

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This paper deals with a new energy saving urban transportation system called "Eco-Ride". The vehicle which does not have on-board driving devices runs using potential energy with the technology of roller coaster. To have good ride comfort for the traveling direction suit for public transportation system, it is important to investigate how to design the vertical track geometry. This paper examines dynamic effects on ride comfort for different cases of vertical geometry. At first, the importance of the vertical curve design is explained by two track shapes. Then, a design procedure of the vertical curve is proposed.

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In this study, the tangent force characteristic between the actual wheel which has fine unevenness, and a rail is estimated. A rolling contact experiment was carried out using the small test specimens which imitated the wheel and the rail, and the influence of fine unevenness of the contact surface on the tangent force characteristic was investigated experimentally. The experimental result showed that tangent force coefficient in the case of contact surface shape has fine unevenness was small as compared with the case where there is no fine unevenness exists because of high contact surface pressure.

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To know the tension of wire is important for safety transportation of cargo. But there is no handy tool for the measurement of wire tension. Some tools were developed that could measure wire tension by applying a load perpendicular to the wire. The displacement associated with the external loading increases tension of wire. So, the tension obtained by the tool is always larger than the initial tension. This study was carried out to evaluate the initial of wire by using the least square method for a nonlinear spring constant model. The experimental result showed the method was appropriate for estimation of initial tension of the wire.

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