In this investigation, curving performance for low-floor light rail vehicles (LRV) with friction controls on wheel/rail interface is discussed. To this end, creep force model subjected to friction modifiers is developed and then the validity of the proposed model is presented by comparison with the measurement data. It is shown with the proposed creep force model that use of friction modifiers on inner track is effective for reducing lateral contact forces of LRV with independently rotating wheels.

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In frontal collisions between SUVs and sedans, it is important to investigate the impact load transfer into the cabin compartments in order to maintain compatibility between both vehicles. In a previous report, the authors proposed the concept of "defensiveness" using new diagrams, D_<CF>(Diagram of compartment force), C_<CF>(Center of compartment force) and 2-D compartment force distribution. In the present study, SUV and sedan models, which are designed as precise 1:10 plastic scale models, are used for experimental car-to-car crash tests. Cabin compartment forces of the SUV and sedan models are described quantitatively by D_<CF>, C_<CF>, or 2-D compartment force distribution. In the SUV model, the compartment force is mainly supported by lower structures, whereas in the sedan model, the compartment force is mainly supported by the upper structure, which includes the door beltline structure.

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This research aims to develop a collision warning system for preventing vehicle-pedestrian accidents by making use of the information of crosswalk position. The system is based on an assumption that all moving objects near a crosswalk are inferred as pedestrians. Crosswalks can be detected by a monocular camera. Moving objects are detected by using a millimeter wave radar or a monocular camera with an optical flow algorithm. In the proposed pedestrian detection algorithm, precise localization of crosswalk is necessary for searching pedestrians near a crosswalk. Consequently, this paper demonstrates a vehicle egomotion estimation by the optical flow, which is useful for correcting the distance to crosswalk during dynamic movements of a car, e.g. large yawing or pitching motion. Test drives show the effectiveness of the optical flow algorithm in estimating yawing and pitching motion.

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The Automatic Obstacle Avoidance System (AOA) using the brake system is developed and made a reality in low speed area but the system using the steering system is not built as the sophisticated theory. This study focuses the steering system and targets AOA by a steered vehicle which is called 'Active Torque Steer (ATS)'. The wheel on both sides of ATS vehicle is equipped with independent in-wheel-motor generating longitudinal force and with scrub radius which is distance of between center of tire ground contact area and tire rotation center. ATS vehicle generates direct yaw moment by using in-wheel-motors and scrub radius. We analyzed AOA of ATS vehicle and compared it with Active Front Steer (AFS) vehicle and DYC vehivle (which is not by in-wheel-motors but by traction and braking force) by simulations of obstacle avoidance. As a consequence, the steer moment and force usage of front tire by ATS vehicle is smaller than that by AFS vehicle and DYC vehicle.

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In the automatic collision avoidance system with automatic steering and automatic braking for automobile, limit time to collision (TTC) is obtained by computer simulation of obstacle avoidance with variation of deceleration. Avoidance method (automatic steering only or both automatic steering and automatic braking) having the shortest limit TTC and the conditions such as deceleration are analyzed. As a result, in ordinary speed range of around 30 to 70 km/h, automatic steering only or automatic steering with about 0.1G automatic braking is better for the obstacle avoidance, if the steering avoidance has priority to the braking.

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The steering wheel hub (called hub, hereafter) is a product that connects the steering wheel and the steering wheel shaft for the car. It has an important function to make it run in the direction where the car is intended. There are two fatigue test standards to test the hubs, one is JASO C713 for genuine products, and the other is the ASEA standard of NAPAC for aftermarket products. The authors have developed a new jig system to do the fatigue test for the hubs. The new jig has specific feature enabling to be applied to any hubs. Moreover, it has self alignment mechanism so that the defined testing force is applied to the hub straightforwardly and properly.

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Currently, fatal accident between pedestrian and vehicle has become the most common accident type in Japan. This study is aiming for the goal of reducing accident between pedestrian and vehicle. We analyzed the Data of Traffic Close Calls in new ways. As a result was able to understand the Environmental Factors and Causes. We classified the data of Traffic Close Calls, and extracted the most dangerous scenes and the most important environmental factors. By calculating RT (Reaction Time) and TTC (Time-To-Collision), we understand the causes and characteristics of the situation between pedestrian and vehicle.

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This paper deals with construction of drive assist system on highway. The senior citizen and the beginner occasionally feel the load by the lane change under various situations on highway. To reduce this, we think about the drive assist to the driver. In the first step, a basic decision-making system was constructed concerning the lane change on ramp. The simulation of the constructed model was executed, and validity was evaluated.

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This study aims to evaluate the effect of drivers' conscientious driving on traffic flow in terms of efficiency, safety and environment. Assuming a signalized intersection where a bottleneck is created by right-turn vehicles, some scenarios were considered that oncoming thru traffic gives a priory right-of-way to the right-turn vehicles to avoid creating bottlenecks at the intersection. The effect of such conscientious driving on traffic flow was examined through simulation trials by a verified traffic simulator. Numerical analysis showed that giving a priority to the right-turn vehicles yields more efficient, safer traffic flow coupled with reduced CO2emission.

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The trial production of pleasure boat hull with resin infusion molding process has been verified for adapting the FRP ship building technology. And the hull of the pleasure boat of 26 ft which has the bottom of the ship with sandwich structure was produced experimentally in order to evaluate the practical use of the resin infusion molding process for FRP ship building. As a result, it was found that working environment was improved, and it was possible to make high quality moldings without needing of expert molding technology but impossible to reduce the total cost.

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The safety of a navigational ship is demanded for the prevention of a marine accident. The causes of a marine accident are collision at the first and strand of a ship secondly. The most of ship's strand causes in the shallow water relatively of the coastal area. It is very important to propose the effective information of water depth for the prevention of ship's strand of the marine accident The present paper proposes the effective expression of information of water depth using GIS for avoidance of ship's strand. The examination of proportion of information of water depth was carried out in Osaka Bay for the example. The expressions of water depth in navigational sea area are two or three dimensional expression of water depth by color and contour line and animation of navigational simulation. It is found that the support of ship's navigation by propose of the information of water depth using GIS is very effective for a officer of a ship managing in shallow water area.

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To solve the serious global warming problem, reduction of CO2 emission is expected in a coastal marine transportation area. As one of the solutions, a Super Eco-Ship project has been executed and several results have been applied for actual eco-ships. Analyses of the propulsion system based on measurements of propulsion shaft revolution and torque are effective for energy saving ship operations. We have analyzed navigation data of a coastal ship in service to clear an improvement in energy transformation for an electric propulsion system. This report shows a comparison of fuel consumption between a normal conducting electric system and a high temperature superconducting system based on actual navigation data of a coastal ship in service.

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Recently the cost effective analysis is recommended when the maritime rules (SOLAS convention) are proposed to change. Automatic Identification System (AIS) equipment has been fitted to all vessels above 500 gross tonnage and to those 300 gross tonnage that are trading internationally. To consider the possibility of expanding the carriage requirements for AIS into small vessels, a preliminary cost effective analysis was done. The effectiveness of AIS was estimated by the marine accidents analysis and the carriage cost was estimated by the number of small vessels and AIS unit price. Finally the effectiveness was converted into cost, and compared with carriage cost in various conditions.

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The disaster at escalator exits draws great attention. This paper proposes a fall detection sensor on the escalator exits. The sensor watches surveillance area with infrared laser, and measures the object position and decides the fall by size and time. Fall detection algorithm finds falling human within 5 seconds while suppresses false alarm caused by crowded people, and send the message to security room. This paper describes the construction and principle of operation, and demonstrates its availability.

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The Aviation Program Group of Japan Aerospace Exploration Agency (APG/JAXA) is conducting research of advanced and fundamental aeronautical technologies based on social and industrial needs derived from diversifying technological requirements and increasing air transport in the future. The background includes the ongoing development of the first passenger jet aircraft produced in Japan after almost 50 years. The primary goals is to develop the cutting-edge technologies which can be applied to the development of competitive aircraft in the world market. To achieve this, JAXA launched a research project in 2003 which covers wide variety of aeronautical science and technologies. This article describes the outline of the project.

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Switching load, which is the force required to bring about switching, is one of important mechanical properties for developing and maintaining the switch-and-lock system and turnout. Measurement tests are only technique to analyze and evaluate switching load, however, it is very difficult to perform the tests for all combinations of switch-and-lock systems and turnouts. Against this background, we are currently working on the development of a method to estimate switching load while aiming to establish a technique to replace such measurement tests. In this report, we present a method simulating contact between two 2D-objects in order to apply multi body dynamics to motion of escapement cranks and switch adjusters. Furthermore, we present a model to estimate the switching load using multi body dynamics, and also present the result of the simulation.

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This paper describes a study of crush behaviour of railway vehicle carbodies under side collision accidents. As the first step for evaluating the carbody side strength, the authors had previously performed static compression tests using full-size partial carbodies, and performed FE analyses in order to verify empirical results. In this paper, we describe the results of dynamic compression tests and FE analysis under the same condition as the tests. The numerical result by FE analysis was consistent with the empirical results in terms of the load-time characteristics as well as their deformed shape. We constructed a method for the evaluation of the impact deformation behavior against loads from the side by using FE analysis.

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This paper describes the development and the verification of the "probe system" which estimates the track conditions without sensors on bogie. To detect the track conditions from the data which can be observed in the interior of a service vehicle, two methods have been proposed: the method to detect track irregularities using RMS of the lateral/vertical accelerations and the rolling of the vehicle body, and the method to detect rail corrugations from the interior noise using the windowed Furrier transform. Video recording function was added to use probe system as Drive recorder function by image. The developed system has been installed onto the cab of a service vehicle to carry out a field test for the validation of the system. As a result of the experiment, Video recording function showed that it became the function improvement of probe system.

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East Japan Railway Company (JR East) developed the hybrid system with the diesel engine and the lithium-ion battery, and began operational service of the world' s first hybrid diesel railcar Ki-Ha E200 in July 2007. This hybrid system could decrease the negative environmental impact of the diesel railcar. The rechargeable lithium-ion battery is selected for the storage battery because of high power and energy density. The deterioration investigation of the storage battery was executed in September 2009 and it is suggested the longevity might be extended for several years from this investigation.

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JR East developed a diesel and storage battery hybrid train to decrease negative environmental impact and the operation has been done since 2007. JR East is developing "Catenary and battery powered hybrid train system" as a new system. A test train "Kumoya type E995" at which the new hybrid system has installed was produced in September 2009, and its examination run was proceeded from October to October 2010.This document introduces the background of the development, outline of the test train and the examination run.

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This paper describes the analysis results of ropeway accidents for last ten years from 1999 to 2008. Analysis includes (1) cause analysis of accidents and (2) occurrence analysis of accidents of the same kind. Aim of this research is to build safety database for ropeways in future. The result shows that occurrence of accidents of the same kind is remarkable and accounts for 94% of the total accidents. Authors find reduction of ropeway accidents requires reduction of accidents of the same kind.

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It is necessary to clarify the information-processing process in a bad driving situation and construct the tool of estimating the situation with bad awareness. In this paper, the narrow course and the obstacle avoidance course are focused on. These courses are the beginner driver's and old age driver's weak situations. Risk model is adopted because of the expression of the maneuvering in a nonlinear variable environment And die probabilistic model is introduced because of the construction and analysis of the process from processing environmental information to construct the risk model. Using this model The process from getting environmental information to steering is classified.

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In Japan, many traffic accidents occur at intersections. Thus, the necessity of countermeasures for safety at intersections becomes evident in reducing traffic accident. Especially, it is thought that yellow light at signalized intersection is more dangerous because of driver's dilemma. In order to realize safe and reliable traffic environment, it is necessary to comprehend driver behavior. In this study, driver model which control vehicle stopping maneuvering at intersection during yellow phase is studied. Drivers characteristic parameters such as time delay, brake pedal stroke velocity during yellow light are identified. In order to evaluate the validity of proposed driver model, numerical simulation with some driver models combined with a vehicle model is elaborately compared with actual driving data.

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This paper describes about method that classify and analysis the driving characteristics between professional driver and Sunday driver to extract individual driving style from urban driving data. Previous individual adaptive driving assistance systems need about 100km urban driving data to assist drivers, and if driving data is not enough, system cannot provide appropriate assist to the driver. To deal with this issue, system must get driver's rough driving characteristics from psychological test or a few driving data. In this research, taxi driver and Sunday driver's urban running data is collected. Relationship between driving experience and time headway is considered. As a result, Driving experience and average of time headway when braking started have negatively-correlate.

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Two kinds of subject experiments were performed to obtain the knowledge of the ride comfort in the vertical curve passage such as perception ratio and so on. The following results were provided from the experiments carried out with real Shinkansen vehicles. It was suggested that not only the acceleration but also the influence of the jerk was strong so that the vertical curve was perceived. In the same condition as the real passengers, the perception ratios of the vertical curve were about 60% at maximum speed 275km/h and about 70% at that 320km/h.

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This paper proposes a driving behavior evaluation method during lane change. To reduce traffic acceidents, it is neccesary to improve not only active safety technology, but also driver awareness about safety driving. One of the methods to increase driver awareness is to automatically evaluate driving behavior and to identify the problems. This research focuses on lane change behaviors and develops the driving behavior evaluation method. To develop this method, the evaluation item are selected and their thresholds are established. Then, the data of driving behaviors in lane change is analyzed using the proposed driving behavior evaluation method.

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It is known that we cannot control a 2nd order delay system. The reason why we can control the lateral motion in the driving in spite of its delay effect is that we can get the advanced information for compensate the delay from the yaw angle or the pass angle. In this paper the authors study the effects of displaying the vehicle direction information to the driver for assist the driving. The results show that the displayed information changes the driving easily. The effect of the pass angle display is not so good because of its delay. The information of advanced pass angle gives the vest effect.

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Using the High beam will improve pedestrian visibility during nighttime driving. However, you will need to evaluate the effect of pedestrian visibility illuminated by headlamps in consideration of human factors, or human dynamics. Thus, we used a fixed-base driving simulator to verify the effectiveness of the pedestrian visibility among several headlamp beam patterns. We verified the effectiveness of the pedestrian's visibility difference between the headlamp beam patterns on the driver's avoidance when some pedestrians suddenly rush out in front of them at night. From the tests described above, we confirmed the effectiveness of high beam headlamp based on the pedestrian's visibility for the nighttime driving.

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The paper studied response of electromyogram (EMG) of sternocleidomastoid (SCM) muscles to simulated motion of the car, which is to clarify the possibility of EMG as an indicator of physical load against head rolling. SCM muscles are in both sides of the neck, and play important parts in lateral stability of the head. The experiment is carried out using a driving simulator. Six settings of motion are designed for the experiment. Two kinds of slalom driving are simulated, and white-noise vibration is added respectively in lateral and roll direction of each slalom driving. The noise simulates vibration inside the car body which results from low rigidness of the car body. The experiment is conducted with 9 subjects and the difference of EMG between settings is examined. The result shows that root mean square (RMS) values of EMG increase significantly when the noise vibration is added.

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There are a lot of maritime accidents caused by human factors. The experiment using bridge simulator is effective for analysis of the human factor. However, the analytical approach for the navigational behavior by the experiment with bridge simulator has not been established yet. The purpose of this paper is to propose an analytical approach by the experiment using bridge simulator that finds out the important factor to avoid accidents. As a result of the experiments and the analysis, it is clearly important that the officers judged the necessary of the constant lookout for dangerous targets. The analytical approach is effective to find the important factor to avoid accident.

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The car has an important impact on the elderly activities of daily living and social participation. However, the physical depression by aging has also the cause of the car accident. In this report, we research about the physical and environmental factors of a car dependency based on a survey. To identify influencing factors, a survey on the attitudes of over 65 years of age people was adopted in a study on 1312 elderly. The investigation revealed that the aging and gender, public transport system were significantly related to mobility activities and driving condition, hi addition respondents living in an aging area have a strong need for a car driving, anxious about the risk of leaving a car and need an encourage improvement of mass transport system.

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Traffic accidents involving elderly drivers are major concerns in Japan. Age-related decline in cognitive function is said to be one of the causes of these accidents, so it is important to propose driving support system considering cognitive ability to reduce these accidents. It is necessary to clarify the relation between cognitive ability and driving behavior of elderly drivers for developing driving support system. We measured cognitive characteristics of elderly drivers and proposed a method to classify elderly drivers based on cognitive characteristics.

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It is important to determine the basis that elderly drivers take unsafe driving behavior in educating driving behavior or developing driving support systems. We recorded about 2000 course driving data of elderly drivers, and analyzed the elderly driving behavior. As a result, we concluded that the decline of physical and cognitive function cause unintentional unsafe driving behavior, and the deterioration of consciousness for unsafety causes intentional unsafe driving behavior.

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The purpose of this study is to evaluate the body load of the wheelchair users on the various road conditions. To verify practical effectiveness of the slope to horizontal conversion coefficient as the index of body load, we measured the oxygen uptake and the wheelchair driving force on the ascending and descending slope course and the equivalent distance level course that is estimated by the conversion coefficient As a result, the oxygen cost index of the slope course and the equivalent level course using the conversion coefficient is almost corresponding, and it means effectiveness of the index. However, it was suggested that we should consider the total energy cost during entire wheelchair running and the influence of fatigue.

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In order to clarify the cause of older persons' unsafe behaviors while driving a handle type electric wheelchair, we extracted unsafe behaviors of older persons by measuring video data of driving a handle type electric wheelchair and measured driving abilities that is supposed to be the cause of unsafe behaviors. As a result, we found that non-confirming safe conditions behavior was the most number of unsafe behaviors and that older persons' divided attention was declined. So, we made hypothesis that the decline of divided attention caused the unsafe behaviors such as non-confirming safe conditions safe conditions behavior. From the experiment using driving simulator, it showed that the subject whose divided attention was declined caused the unsafe behavior such as not confirming the traffic signal and that the decline of divided attention might be the cause of the unsafe driving behaviors.

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This thesis describes the development of a new mobility of the skateboard type. The car and the public transportation facility, etc. are used as methods of transport now. The advantage and disadvantage exist in transportation. Then, to use the advantage of transportation to its maximum, the mobility that can be brought in the car and public traffic is developed. To board it easy operation, the mobility applies inverse pendulum control. Driver's center of gravity location information is used as substitution of driver's angular information for the control. The operation verification of the straight advancement and the turn is being done with an experiment machine now. A further improvement of the airframe and control techniques will be done based on present the mobility data.

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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 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.

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A wheel-type personal mobility robot is expected as a personal transportation machine near the future. In this paper, a new transportation system combined with a personal mobility robot and a train transportation is proposed. The personal mobility robot supplements a weak point of the train transportation, that is, lack of door-to-door movement. Some wheel-type personal mobility machines have been developed. While the Segway is one example of the practical use machines, those machines can not have high mobility on discontinuous rough terrain like a step. In this paper, a personal mobility robot that can move on discontinuous rough terrain is also introduced.

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A new type dual mode transportation system called as "Bi-modal Transportation (BMT)" have been under development for several years. The BMT is based on technology of buses, and it has characteristics both of guided transportation and conventional road transportation. The technical points of this system are contactless vehicle guidance, mechanical coupling and automatic wheel steering. Two experimental BMT vehicles with non-step low floor have been built up, and proving tests are going to be carried out.

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A high energy-saving new small urban transport system "Eco-Ride" moves under potential energy and has merits of low initial costs and high flexibility to install. To improve the comfort and accessibility of vehicle for Eco-Ride, a design evaluation method of passenger rooms has been proposed by combining the comfort and accessibility evaluation models for light rail vehicles and automobiles. The results of boarding experiments at full-scale Eco-ride mockup has been applied for the quantitative comparison of design layouts for passenger rooms of Eco-ride experimental trains. No statistically significant difference in comfort evaluation values of seats was found between the full-scale mockup and the manufactured experimental train about the experimented seat arrangement. Evaluation formula of passenger rooms is composed from experiments.

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We proposed a robust method for self-localization of infrastructure-free automated guided vehicles (AGVs) using laser range finders (LRFs) in environments that include multiple vehicles. In those environments, occlusion of a LRF is caused by other vehicles, and false localization occurs with a conventional method. To solve this problem, our proposed method was divided into two stages. In first stage, to distinguish other vehicles' sides from walls, an AGV detects other vehicles with retroreflective materials from environments' shapes and reflection intensities measured by only a LRF. In second stage, to complement information for self-localization, an AGV integrates measurement results of a LRF and information of wheel rotation using Kalman Filter. Our method has an advantage that it doesn't need any additional infrastructures or electronic devices.

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This paper proposes a mobility system for a robot. The purpose of this transport system are the followings. 1. realizing of an efficient and safe system under a situation where multiple robots move around ; 2. realizing of a safe and comfortable system for a driver and surrounding people ; 3. realizing of coexistence of autonomous robots and manipulative robots. And, we extract a good point of the existing transportation system and introduce this system. This system can be applied to unmanned distribution system. In this paper, we developed "Area Control module" and "Obstacle Avoidance Control module" to prevent a collision with an object.

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This paper proposes SSM(Sensor Steering Mechanism) for a lateral guided vehicle with an articulated body which has an arbitrary position of bending joint. The last paper shows the SSM for an articulated vehicle with a bending joint located at the center of its wheel base. The articulated robotic vehicle designed by SSM is demonstrated an accurate line following at low speed and a drift cornering in the corner at high speed moving. This paper leads SSM for an articulated vehicle with an arbitrary position of bending joint and constructs an experimental robotic vehicle controlled by the proposed SSM. The experimental data show the advantages of proposed SSM.

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Ensuring fault tolerance of robotic systems is a challenge for factory automation. For this challenge, we propose behavior coordination strategies and optimal maintenance policy for multiple mobile robots. The coordination strategies enable a system to continue operating even if a working robot undergoes preventive maintenance or fails and undergoes corrective maintenance. In addition, working robots are allowed to undergo preventive maintenance at an optimal interval and corrective maintenance each time they fail. Finally, through simulation experiments, we demonstrate that the behavior coordination strategies and optimal maintenance policy are both effective for the fault-tolerant systems.

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Advanced Mobility Research Center (ITS Center), Institute of Industrial Science, The University of Tokyo has approached to improvement of realistic sensation on the Universal Driving Simulator for Human, Vehicle and Traffic Research (DS). Some functions such as a turntable mechanism, a new visual system with the target projector to improve visibility, improvement of a sound system, etc. have been added before now. Moreover, the new mechanism consisting of XY-stage and turntable mechanisms was proposed and developed for upgrading realistic sensation of the DS and applying the DS to experiments on automobiles. The new mechanism can be installed on the top of an existing 6-DOF motion platform of the DS. In this paper, concept and structure of the new mechanism are described.

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