Railway vehicles have been reduced the car body weight for energy-saving, noise-reducing and speed-up. However, it triggered the increase in a vertical vibration because stiffness of car body was reduced. Human being feel especially distasteful by frequency of the vibration, ride quality became worse. Therefore, Railway vehicles have actuator to control vertical vibration. And vertical vibration was reduced. But it cost more money and increase weight of car body to set up actuator on railway vehicles. So object of this study is to control vertical vibration by air spring which is secondary suspension of railway vehicles. And it is investigated with the vibration experiment to reduce elasticity vibration by controlling air spring.

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Most of the small electric vehicles use in-wheel motors as a driving system. To enhance braking performance and energy regeneration, we introduce a new simulation model of hybrid brake system with PID controller for small electric vehicles. The rear brake was assumed to be a regenerative brake produced by two independent rear in-wheel motors. In this study, the effectiveness of the P, PI and PD controller to our hybrid brake system was observed. The function of this controller is to control the deceleration G. The effectiveness of the proposed skid control method was evaluated by MATLAB-Simulink. The simulation results show that the output of the deceleration G with PI controller is nearest with the input G compared with P controller and PD controller. From this result, it is approved that hybrid brake system with PI controller can improve braking performance.

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Wear development with polygonal shape on a rotating elastic body is a kind of pattern formation phenomenon in mechanical vibration. The polygonal deformation occurs gradually, and this causes strong vibration and noise in machine operations. This phenomenon is a kind of self-excited vibration due to time lag and eigen characteristics gives an explanation of the stability of the system. This paper deals with the experimental approach of this pattern formation in order to discuss about the polygonal numbers of the shape, giving the various rotation speed and slip ratio. The effect of the disturbance given as a groove on the surface on the stability is also examined. It is pointed out that the unexpected polygonal number appears during the rotation in the case of the large disturbance.

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This paper describes the measurement method of the contact condition between the wheel flange and the rail gauge corner. One of the most essential factors causing the flange climb derailment is the increase of coefficient of friction which is closely related to the surface condition of wheel flange. The purpose of this study is to clarify the mechanism of the increase of coefficient of friction from the aspect of visualization of the contact condition. In this study, we have proposed the measurement method for the contact shape and pressure distribution between the wheel flange with complicated surface figure and the rail gauge corner using the ultrasonic technique and the subtraction imaging method. And, we have confirmed the shape and pressure distribution of contact area by this method.

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From a point of view of handling and stability, it is important to bring automotive tires into contact with the road correctly. But it is difficult to know if tires contact with road correctly or if tires produce the force enough to drive safety while moving. In this research, by measuring the deformation of tires with the strain gauges attached in the inner liner, we figure out how to estimate contact patch's condition or side force of the tire.

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This paper describes ropeway safety database built based on analysis results of ropeway accidents and incidents. Safety database includes (1) ropeway basic data, (2) accidents and incidents data, (3) analysis reports and (4) lesson database of accidents and incidents. Aim of this research is to reduce ropeway accidents and incidents with the help of ropeway safety database. Further safety measures are expected to be taken on the basis of lessons learned from the past accidents and incidents.

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The three dimensional detection of the center of gravity, which is abbreviated to D3DCG, is the innovative technology by which the center of gravity of moving objects can be detected within less than half a minute. The first application of D3DCG was the rollover prevention system for trailer trucks. Recently D3DCG has been innovated to detect deterioration of springs, suspensions and tires of moving objects. This paper reports results of experiments on detecting deterioration of tires of an automobile by activating D3DCG on it under driving at about 15 to 20 km/h. The detection was perfectly achieved by D3DCG.

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Armored fighting vehicles with Mine Resistant Ambush Protected (MRAP) designed to counter Improvised Explosive Device (IED) have attracted special interest recently. This paper describes dynamic response of the shock absorption seat to blast load. Mathematical models have been developed to predict the effects of the blast load on the seat-passenger systems. We propose hook-spring mechanism which consists of two springs (hook-spring and cushion spring). Hook spring (hard spring) supports seat and human under normal operations. When they receive the blast force, they tear loose from its spring. After then cushion spring (soft spring) support them. The effect of the hook-spring mechanism seat to blast load is confirmed by numerical simulation and experiments.

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The use of child restraint systems (CRS) decreases child's risks of severe injury in collision accidents. However, child's risks of injury are still high in side impact crashes. Recently, it was decided that the side impact test is introduced into the new regulation for the universal ISOFIX type CRS at a meeting of the United Nations Economic Commission for Europe. At the time of the introduction of the side impact test, it is useful to understand behaviors or responses of the occupant seated in a CRS in a side impact crash. Therefore, full-scale vehicle side impact tests were performed with a Q3s child dummy seated in a CRS. Two kinds of simulated striking vehicles and three impact positions where a simulated striking vehicle crashes into a struck one were combined in the test conditions. The following three conditions were set; I: a condition based on UN Regulation No.95 test procedure, II: the impact nosition different from the condition I, III: the impact position and the simulated striking vehicle different from the conditions I and II. In this paper, behaviors and injury measures of the occupant seated in a CRS are compared at three test conditions.

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It is very important to prevent the ships from global environmental pollution and to reduce emissions of greenhouse gases. So it is considered very useful with the object of the prevention of environmental pollution to use hybrid ships which operate by batteries in case of it is near from human habitation and they operate on port district is easy to give off an exhaust is produced by the incomplete combustion by the start and stop of the engine. Therefore, in this report, we consider to navigate by all the batteries when it comes into and leaves a port, and it calculates necessary battery capacity, size and charging time, as an example, it cover the several ships navigates in Tokyo Bay, and we discuss about navigation methods to take on batteries of large capacity. It values at number of a container in the way of the batteries put in a familiar container for the ships as for battery size. This shows between superimposed capacity of the cargos etc and battery size, and it complies battery capacity which mounted, and this report discusses battery about the charge methods and the battery charge time. And it shows practical navigation methods as hybrid ship.

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One of the recommending solutions for greenhouse gas reduction is eco-driving in recent years, which requires driver to carefully operate accelerator and brake of vehicle. However, eco-driving may results in stressful driving for driver. In the study, driving parameters of vehicle and bio-signals of driver are proposed to assess the driver's stress during eco-driving. In an actual truck driving experiment, vehicle data and physiological indexes of driver were measured during eco-driving in public road. The results show that pedal effort and electromyogram of triceps surae muscle are strongly related to driver's stress, and can be used to assess driver's stress during eco-driving.

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This study discusses a collision avoidance technology designed to improve the safety of small or micro-sized vehicles. In this paper, autonomous steering experiment by the automatic steering system by micro electric automobile (ATS Vehicle) which steered the front tire by right and left driving force difference and kingpin offset is carried out. Autonomous steering utilizing 'Active Torque Steered' (ATS) vehicle is proposed and evaluated performance of collision avoidance using simulation of critical avoidance time compared with autonomous braking of this vehicle.

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In Japan, the number of fatalities regarding pedestrians still remains large number. In order to prevent traffic accident for pedestrians, predicting hazard for pedestrians becomes important in the design of driver assistance system and ITS technologies. This paper focus on the modeling of hazard-anticipatory stopping behavior model during yellow phase at signalized intersection. In this study, near-miss incident with pedestrian at signalized intersection collected with drive recorder is analyzed. Utilizing three indices reflecting risk for stopping, entering and passing, driving model is constructed and evaluated in terms of braking timing before entering signalized intersection during yellow phase. Especially, this paper describes how to decide the braking timing for preventing actual near-miss incident in signalized intersections.

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This study examines the assistance system to predict driving behavior considering the pre-preceding vehicle information. The assistance system indicates an evaluation index considering not only the relation (Time HeadWay) between the preceding and following vehicles, but also the relation (Time To Collision) between the pre-preceding and following vehicle. Driving simulator experiments are examined with several participants who follow a preceding vehicle and a visible pre-preceding vehicle. The participants with the assistance system succeeded in following the preceding vehicle with small acceleration and a small standard deviation of evaluation index of collision risk (Risk Perception), whereas the participants without the assistance system with large acceleration and a large standard deviation of evaluation index of collision risk.

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To reveal a possibility of detecting the direction of the sound such as in-vehicle warning, authors conducted the indoor test using 15 young and 15 elderly subjects. Speaker positions were selected in six ways (three in the front, three back), sound pressure levels were set three types and five combinations of sound frequencies were adopted. On the results of experiment, we could reveal the difference of easiness of detecting the warning direction according to speaker positions and other factors.

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Drowsiness causes fatal and heavily injured traffic accidents, therefore a number of studies on the detection of drowsiness or on the inhibition of it have conducted. In present study, electrocardiographic measurement which is one of the most convenient measurement methods for subjects and experimenters was chosen to detect of drowsiness. The variations of RR-Interval and autonomic nervous system indexes during mental arithmetic and driving vehicle were compared by employing frequency analysis and Lorenz plot as analysis method.

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The paper clarified the movements of driver's body and ride comfort in low frequency lateral acceleration, when the seat stiffness distribution varies. The four different conditions of seat stiffness distributions were designed by the mechanism using two types of rubber beltings, and driving experiments were carried out using a driving simulator cooperated with 6 subjects. The result shows that roll and lateral shakings of driver's body can be reduced effectively, when the stiffness of upper side of the seat becomes higher, hi contrast, roll shakings can't be reduced, when the stiffness of lower side of the seat becomes higher. The activities of driver's muscles also depend on the seat stiffness distributions, and amplitudes of electromyography of the muscles decrease when the seat stiffness becomes higher. That result corresponds to the magnitude of movement of driver's body.

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Driver is steering, keeping his/her posture and holding steering wheel during driving cars. Holding steering wheel has good effects on stability of cars, but the mechanism of it isn't understood clearly. We did steering wheel shaking experiment and identified of mechanical characteristics of driver-steering system. Firstly, shoulder support ofseatback decreased inertia of driver system, but it didn't have effect on stiffness and viscosity. But it decreased muscle activity to keep driving posture, and helped to push steering wheel easily. Secondly, holding steering wheel tight didn't have significant effects on mechanical characteristics of driver-steering system. But we need measure steering wheel grip force accurately to discuss effect of holding steering wheel in more detail. Finally, pushing steering wheel increased stiffness and viscosity of driver system. And contributing rate of geometric stiffness to increase of stiffness with pushing steering wheel was estimated at about 20-30%.

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Many types of driving assistance systems have been developed in recent years. To achieve using continuous support for the drivers, haptic feedback has been proposed for more accurate driving, and it has some advantage compared to visual or auditory assists. Also, condition monitoring of a driver is considered important to assist the driver effectively. This paper deals with an experiment of haptic guidance steering system and monitoring of a driver's stress especially on highway. The driving experiment under four conditions is carried out; ON/OFF haptic guidance, and WITH/WITHOUT other traffics. By comparing driven data, effectiveness of haptic guidance and estimation of neuromuscular admittance is examined. As a result, driving with haptic guidance has shown smoother control of steering. Also, admittance decreased when other traffics exist, which is considered more stressful.

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This study identified control inputs of riders which operated a two-wheeled vehicle, and cleared influence on outputs. We analyzed frequency characteristic to find out control inputs of riders in lemniscate course. As a result, We clarified that the steer torque of the Z-axis and the seat torque of the X-axis have influenced to yaw velocity as the control inputs. In addition, the steer torque of the X-axis has influenced to lateral acceleration.

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Human errors tend to occur during emergencies in which emotional arousal level is extremely high. Although research on human behaviors in emergencies exists that looks at mass panic and/or provides case studies, few studies focus on individual behavior in emergencies and employ experimental techniques. In this study, participants played the "water-pipe game" under conditions of "time pressure" and "severity" designed to increase arousal. ("Emergency" consists of both these factors together.) They were asked to push the button as early and as precisely as possible when a target appeared at the center of the monitor. Experimental participants' click frequency increased and their thinking time declined under the high-arousal condition. This was not so in the control condition. Furthermore, the miss and false alarm rates were higher in the control condition. In conclusion, when emotionally aroused in an emergency situation, humans tend to act promptly without active thought and to overlook events that are not related to their actions.

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Authors conduct a survey of the elderly on items including lifestyle, behavioral pattern, and walking speed for preventing traffic accidents involving elderly pedestrians crossing a road. The result shows that the elderly often cross a low-traffic volume road they are familiar with in their neighborhoods, which does not have a crossroad. We also investigate the pedestrian-to-vehicle distance which makes a pedestrian give up crossing a road on a two-lane course in a driving school. As a result, it is found that the pedestrian-to-vehicle distance is longer when a vehicle is approaching from the pedestrian's left than from his or her right, and the pedestrian-to-vehicle distance increases as the vehicle speed increases/Also, when a vehicle speed is 40km/h or higher, the time taken for a vehicle to reach a pedestrian is shorter than the time taken for a pedestrian to cross a 7m-width road. Therefore, the vehicle approaching from the left may collide with the pedestrian. It is suggested that enhanced countermeasures against pedestrians on the right side with respect to vehicles are important.

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Head-on collision accident's fatal and injury percent is highest in all fatal and injury accidents. Therefore, it is important to study and develop active safety technologies for Head-on collision. As part of this, in order to clarify the principal causes of head-on collisions and to establish a reference model when passing through unsignalized intersections without the right of way, the experiment was conducted on the test course using the experimental vehicle to collect driving data of expert drivers, hi addition, the simulation model is constructed based on these data in an effort to clarify the safety driving behavior. This paper describes the change in driving behaviors before and after change at intersection environment and the evaluation of it by the simulation model.

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In order to improve drivers' driving skill, this paper proposes a statistical method to extract the operation characteristics between high-skilled and low-skilled drivers from obtained data at driving simulator experiments in curve sections. A driving skill determining model is built using the extracted features so that the driving skills of an unknown run can be classified automatically. And based on the extracted result, we supplied advices to low-skilled drivers in experiments. The results are also descripting in the paper.

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This paper proposes a new running mode for personal mobility vehicle (PMV). Generalized running modes in PMV are known as an inversed pendulum vehicle and a bicycle. This proposed mode is to connect between the pendulum mode and the bicycle mode. In case proposed mode has possibility to use in practical, it is able to change between the pendulum mode and the bicycle mode during a running state. In this paper, a test vehicle with asymmetric wheel alignment to examine a running stability in the asymmetric wheels. Moreover, usage of proposed mode is verified by the running experiment.

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Mobility including transferring is one of the important activities of daily living. In today's aged society, the importance of assistance for the people with limited mobility is acknowledged. Therefore, we propose that the personal mobility vehicle (PMV) for the people with limited mobility. Proposed PMV is propelled by kicking motion with power assisted wheels. It aims to assist short distance transportation in urban area e.g. moving from a home to a train station. By using a folding mechanism, it will be able to take on to the public transportations and will help to extend the area of the user's activities. In this report, it is introduced about our 2nd prototype PMV.

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To evaluate the possibility of collision in the driving environment of handle type electric wheelchairs, we suggested the collision predictive index based on the analysis of the video image data of driving handle type electric wheelchairs and examined the validity of it in comparison with the risk perception data obtained from expert sales persons. By using this index, we can quantitatively evaluate the possibility of collisions with pedestrians, bicycles and the rushing out from blind spots. As a result of examination of validity, we found that the collision predictive index could correctly identify 63% of objects within the range of the scenes we analyzed.

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Personal Mobility Vehicles (PMVs) are sometimes used in pedestrian areas. It is important to discuss the safety and comfort of PMVs in pedestrian areas. In this paper, the interaction between PMV and pedestrians is investigated using the personal space. Especially the influence of the assist control of PMV on a pedestrian's PS is evaluated in the simulation. We simulated three conditions, "No assist", "Assist with avoidance control", "Assist with velocity and avoidance control". From the simulation results, it was found that there is best acceleration to decrease invasion ratio. When the width of road is narrow, it was shown that "Assist with velocity and avoidance control" effectively decrease "Invasion ratio".

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We propose a supporting steering control system using IR for a personal mobility vehicle (PMV) to pass through a narrow space in indoor environment. This system consists of IR markers located on an entrance or on the way of the narrow space and an IR sensor mounted on a PMV. An IR sensor calculates relative angle as an angle of approach and distance between itself and an IR marker to pass through on a marker. To validate the proposed system, we performed the experiments to estimate accuracy of calculated relative angle and distance. Furthermore, we demonstrated automatic control using by our manufactured PMV 'RT-Mover P-type2' with the system. These results showed that the proposed system is effective in path guidance for PMVs.

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For the development of a personal mobility vehicle which can utilize the public transport systems without supports by the others, an information service system is developed in this paper. For the information service system, ultrasonic wave transmitters which are attached to the environment and a receiver which is attached to the vehicle are developed. The information service smart phone application and the mobility vehicle support server are also developed to provide the environment information to the user (maps, the position of the use, etc). In the real environment, the experiments had been held to certify the ability of the system.

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Recently, the maintenance of bus routes has become a difficult situation due to the progress of motorization and rapid progression of aging and depopulation in the whole country. Many municipalities have introduced Demand Transportation as a countermeasure, ensuring profitability becomes a big problem. In this study, it proposed the method of utilizing the empty taxi and the taxi waiting passengers at stations unenforceable in the current law, and it simulated on the Tamaki town, Mie Prefecture. As a result, it was found to be 31.2% reduction in the commission fees by utilizing it.

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Based on the analysis of elderly driver's real driving behavior, we classified unsafe driving behavior 4 categories by focusing the consciousness and the intent. By extracting the causes of unsafe driving behavior, we propose two effective education methods. One is the method to have students grasp their own driving behavior objectively. The other is the method to raise their safe driving consciousness. We verified the effect of these education methods. To classify the characteristics about an elderly driver's educational, we made an experiment that compares the educational effect of the elderly drivers and the young drivers.

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The steering reactive torque of an automobile is one of the important information for a driver to estimate vehicle behavior and road conditions. This paper describes enhancement of the execution period in steering torque simulator with multibody vehicle model. We considered the formulation of multibody dynamic analysis in steering torque simulator and embedded the matrix libraries to multibody dynamic analysis in steering torque simulator. This approach realized the stable analysis considering the nonlinearity of friction characteristics and so on. The runnning tests were conducted with developed simulator and the actual vehicle in order to evaluate the reality of the steering torque simulator.

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Each driver has own driving style such as grasping pattern of steering wheel, bodily characteristics and driving position. Thus, handling feelings vary from driving style even if it is the same steering system. In this study, aiming at improvement of handling feeling, we examined the influence of driver's grasping characteristics on the handling feeling by measuring driver's steering behavior and grasping pressure distribution. As the results examined by various cross-sectional grips, in the case of better subjective evaluation, the grasping pressure was lower, the pressure change was smaller, and the range where pressure applied on was partially concentrated on the grip. Meanwhile, the difference in surface hardness of grip greatly affected on the pressure distribution of a palm when steering wheel was operated. Therefore, it was suggested that the grasping pressure distribution was deeply related to handling feeling and could be the objective evaluation index for the handling feeling.

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In this study, a methodology for estimating the collision mitigation ratio of collision-avoidance support braking system is discussed, taking a driver's risk-taking behavior into the calculation. First, the driver's viewing behavior was investigated in a driving simulator by changing the control timing of the collision-avoidance support braking system. Viewing behavior was identified in terms of the duration from looking off a proceeding vehicle to looking back and braking behavior was identified as reaction time for braking in order to avoid a collision. In this analysis, the driver's braking behavior was investigated not only under the system's proper operation but also under its non-operative condition. Next, to investigate the combined effect caused by a driver error and the collision-prevention support system error, the time series reliability model simulating its operating status was constructed. The effectiveness of the system with different control setting was quantitatively compared as the collision frequency and as the collision velocity calculated through time series Monte Carlo simulations.

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The study is to analyze driver's behaviors for emergent avoidance using override system in a truck-driving-simulator. Thus, a truck driving simulator was constructed by our research group, to grasp the complicated state of undergoing interaction of control systems, human, and trucks during automatic platooning. A full-scale cabin of truck, a gap distance controller for longitudinal and lateral directions, steering equipment, a seat suspension, and a sound generator based on actual-vehicle driving are integrated into a universal driving simulator. The experimental studies for 12 subjects were excuted in the two trucks following mode, and in the conditions of only braking, only steering, and braking plus steering. The results indicated that the braking operation with override control is an effective resolution for emergent avoidance during the automatic platooning of truck.

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Generally, Using many sensors is easy way to make servo for mechatronics. Although, how to use sensors are not so much thought in those case. Sensor fusion is one of the ways to use sensors to get much non-noisy signals for control. However, it is feedback signal that is passed filters made via the Sensor fusion is compared to only one demanded signals. We suggest new method that let feedback signals to be compared multiple demanded signals. Especially, in this paper we show the controller synthesis and its simulation. Then, we also show about possibility to control motion simulator by our method. For example, driving simulator and shaking table are considered.

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