This paper presents the effective and practical method for experiments of comfort evaluation of trains using a motion simulator. The experimental plan was considered from various viewpoints such as cabin vibration condition, the questionnaire sheet, passenger situation, reality and total efficiency of the experiments. From the experimental results, it was confirmed that even in the same vibration condition, the tendencies of evaluation differed, and that the tendency of the change of evaluation differed according to the change of vibratory and constant acceleration, by subjects' body posture - sitting, standing, and walking.

View full abstract

We evaluated the fatigue to occur by sitting on railway vehicle seat for long time, and used by finger plethysmogram. For using the finger plethysmogram data, we evaluated the muscle fatigue and comfort. We compared fatigue to occur by sitting for two type seat, the seat type of stabilized last position and dispersed human body pressure. As a results, there were a little the fatigue seat type of dispersed human body pressure and showed a tendency the same as subject judgment. And, we examined the fatigue when I added vibration by a motion simulator. There were an upward tendency on the fatigue, we evaluated an effect on vibration for sitting seat.

View full abstract

Recently, customers' sense of values and demands diversifies and customers request more comfortable cabin space. In our new high-speed test train "FASTECH360S", it aimed at the achievement of the car interior that satisfied customer's demands, and the more comfortable space for the future was developed. This paper reports on the application of ideas for more comfortable cabin space, for example, a concept different in each car applied to the cabin interior design in order to suit each customer's comfort and a new concept applied to the new sanitary space for customers' comfortable space. For more comfortable atmosphere of the cabin space, we developed three types air-conditioning system that had a humidifying and a dehumidifying function. And we had comparison tests of the air-conditioning system of three types. In addition, we had tests of air-conditioning control system through wireless local area network from personal digital assistant for more usefulness.

View full abstract

A new measuring method introduced in this paper can measure contact forces between wheel and rail without special wheelsets with slip rings or telemeters. In this method the lateral contact force is measured from the lateral distortion of wheel measured by several non-contact gap sensors. The measured values are small, but accurate value of lateral force can be calculated by the compensation of axial movement and inclination of wheelset. Normal and longitudinal contact forces are also measured from the strain of parts of the truck except wheelsets. According to the results of full-size truck stand tests and train running tests, we have verified that the new method has sufficient accuracy of measuring compared with conventional methods.

View full abstract

This study deals with wheel flange climbing, which is one of the causes of derailment. The experiment using a single axle truck shows a tendency in which the increase of attack angle and the decrease of static wheel load ratio make small the necessary external force for derailment. Here, it is shown that the influence of the latter is small. In the numerical analysis with an analytical model that is built based on experimental results, not only the attack angle but also static wheel load ratio affect the derailment largely. The wheel tread lifting and wheel flange climbing, those are observed in the experiment under the condition without the external force, also can be simulated with the analytical model.

View full abstract

It is important to prevent commuter trains overrunning which are caused by human errors. Although skillful drivers can robustly withstand drastic changes to situations, they may make a mistake. In this paper, we focus on a braking control problem in which the task of the human operator is to make the train stop exactly at a given position. We propose a support system for the human operator, which applies so-called Just-In-Time modeling to predictive control. Moreover, we propose a human-machine interface system which displays the level how far the current manipulation apart from the usual ones by using an input-output database. The effectiveness of the proposed method is demonstrated by simulations of a braking system on trains.

View full abstract

For the safety of train operations, it is very important to investigate the aerodynamic characteristics of railway vehicles under strong cross winds. We have studied to simulate flows around a train in natural winds. In this first report, we show numerical computations for generating inflow turbulence. We generated two types of inflow data. One is a turbulent boundary layer on a smooth surface and the other is that on a rough surface. We also conducted wind tunnel experiments to verify the computational results. While the computed result on the smooth surface shows good agreement with the experimental data, the turbulent intensity on the rough surface by the numerical computation is less than that of the experimental result.

View full abstract

This paper performed examination about the safe information by IC tag. IC tag is used now in various fields about product information and history information. However, the next condition is necessary to transmit safe information. 1) Energy condition: A signal that means safety is related to high-energy state (ON signal) while a signal that means danger and failure is related to a low-energy state (OFF signal). This is for the purpose of preventing notification of safety in error for that of danger. 2) Predictability; Allowing the safety-related information to have time necessary for predicting fatal accident and avoiding it beforehand. 3) Unateness: In case of a system trouble, output signal is always held on the safe side (operation-stop side). 4) Robustness: Detection characteristic remains or changes to the safety side even if an environmental change occurs. In this paper, perform basic consideration about safety information and functional information. And perform experimental examination about an information generation condition.

View full abstract

A layered safety control system is a most important concept for servo-drive control. An upper layer deals with information on achieving a system-defined target. Correction of errors included in information is allowed through later review. Accordingly, a control model for this information is expressed by feedback system. On the other hand, a lower layer deals with information on protecting a system. Correction of errors is not allowed through later review because errors included in information may invite fatal accident. Accordingly, a control model for this information is expressed by interlocking system. This report shows safe requirements in designing safety related parts of servo-control. The basic configuration of layered safety control system, basic characteristics of safety information and the necessity of absolute space monitoring related to safety limits were clarified in this study.

View full abstract

This paper describes a part of incident situation of driver especially on vehicle sideslip situation. Nowadays, many researches aiming to develop the driving assistance system for decreasing traffic accidents are being conducted, but the best way to deal with this problem is to study about the main source of the accidents, that is driver. This research focuses on the driving behavior while doing double lane change and when the road friction is reduced suddenly by using driving simulator, which can be recorded to analyze the pattern of incident so that if the behavior that driver is going to do can be analyzed, the event that will be occurred can be predicted. Data are collected and used to find out the causes of incidents and the factors informing about the car spinning out of the course. In future, all of data will be used to synthesize the assistance system for assisting driver before accident happens.

View full abstract

Recently, as part of ASV (Advanced Safety Vehicle) development, some manufacturers have been developing "drive recorders" that record data when accidents occur. If this data has been recorded, it can contribute to determining responsibility for the accident and to preventing similar accidents in the future, but there is a problem with the reproduction accuracy of the data. As a first step toward resolving this problem, we conducted a study of the reproduction accuracy of vehicle trajectories and vehicle speeds. Reproduction accuracy of trajectories is not uniform, due to the cumulative effects of error resulting from multiple factors, including the time of the reproduction, zero point drift, changes in vehicle orientation, and irregularities in the road surface. We therefore first used a simulation to compare theoretical trajectory calculations with trajectory calculations that incorporate measurement error for various parameters, and identified the theoretical error for vehicle trajectories.

View full abstract

This driving simulator study focuses on false and missing alarms produced by a forward collision warning system and estimates the effect of alarm timing on driver response to alarm malfunction from the perspective of driver trust. The results show that drivers who experience late alarms are reluctant to respond to a false alarm and are not influenced by a missing alarm, however drivers who experience early alarms tend to respond to a false alarm and suffer a delayed response to critical situations following a missing alarm. Furthermore, drivers whose judgement of trust is relatively high, tend to exhibit delayed braking, compared with drivers who have lower levels of trust. These results suggest that driver behaviour towards false and missing alarms may vary according to alarm timing and its influence on trust in alarms, moreover there is a possibility that the negative effects of alarm malfunction may be mitigated by manipulating alarm timing.

View full abstract

In this lecture, I will discuss the situation of the automobile theft and the countermeasures to the automobile theft in Japan. I believe that the Immobiliser and The Vehicle Security Assessment are effective countermeasures, contributing to the decrease of the automobile theft in Great Britain in 1990's.

View full abstract

It is important to obtain the stress frequency distribution by service load in order to estimate the fatigue life in welds of Vehicle truck frames. Although the stress frequency distribution by service load can be obtained by vehicle running test, it is difficult to estimate the distribution in the stage of design. Accordingly, the characteristics of stress frequency obtained by the past running test data were examined and analyzed together with its analysis of the effect of running conditions, which include distance, speed and payload. The study results will be used to estimate the stress frequency distribution in the stage of design.

View full abstract

The objectives of the present paper are to evaluate the statistical fatigue properties of welded joints and to apply to the fatigue design standard of railway bogie frame. Fatigue tests were conducted on welded joints with unfinished weld toes, i.e. As-weld, and weld defects. As a test result of As-weld, a new stress evaluation method, in which the location of strain gage was modified, was proposed. Then the allowable stress for fatigue design measured by the proposed method was determined. On the other hand, the fatigue strength of the weld joints with weld defects was evaluated from the point of view on the fracture mechanics. As a result, the allowable stress intensity factor was determined. Finally, the difference between the proposed fatigue standard and the other standard/reference data was discussed.

View full abstract

This study proposes a fault detection method for a railway vehicle. The Interacting Multiple-Model (IMM) algorithm which choose probable model from multiple models using estimated results is applied to the fault detection. Two models are assumed for a normal vehicle model and a vehicle model with fault. The fault detection is examined from the estimated states of the two models using IMM algorithm. Simulation results show the method is effective for fault detection of the railway vehicle.

View full abstract

Conditions of track have conventionally been measured using exclusive inspection vehicles. If the conditions of the track can be detected by attaching simple sensors such as accelerometers on board, more efficient maintenance of tracks would be possible. This paper describes rail corrugation detection from vertical acceleration of a vehicle body and the running noise by time-frequency analysis. An actual vehicle experiment in real route was conducted which measured vertical acceleration of axleboxes and a vehicle body, and exterior noise. Multi-resolution analysis (MRA) of wavelet transform is used to analyze the vehicle body acceleration. It is shown that the rail corrugation can be detected by MRA. A method to detect the rail corrugation from the running noise is suggested, and the noise measured in actual vehicle was analyzed. The result demonstrates that incipient corrugation can be detected effectively.

View full abstract

This paper describes the estimation algorithm of the vehicle state and the road condition. This algorithm is formulated based on the Interacting Multiple Model (IMM) algorithm. Ten system modes are modeled according to the road friction. Changes of the ten system modes are also modeled as switching from one mode to another in a probabilistic manner. The mode probabilities and states of vehicle are estimated based on Extended Kalman Filter (EKF). This algorithm is evaluated in simulation study. Simulation results show that the algorithm is effective in the state estimation of vehicle and road surface.

View full abstract

Pitting corrosion is typical corrosion observed on coated hold frames of bulk carriers which exclusively carry coal and iron ore. In order to ensure the safety of these types of bulk carriers, it is important to understand the effect of pitting corrosion on local strength of hold frames. In order to investigate this effect, a series of non-linear FE analyses has been performed with pitted plates under combined axial compression and shear. It has been revealed that ultimate strength of pitted plates subjected to compression and shear loads is smaller than that of uniformly corroded plates in terms of average thickness loss of the whole plate and prediction results of ultimate strength using average thickness loss at the minimum cross section would be conservative. An evaluation method of residual strength of pitted plates was developed as a function of DOP (degree of pitting intensity), pit diameter and original thickness of the plates.

View full abstract

This paper covers sensing technology for the condition of forward road surface. The change of refrection power of scanning laser rader was used at scanning road texture of forward road in order to be connected with road texture and coefficient of friction. At first, This experiment discusse about variation in factor of refrectionpower in oder to recognize road texture particularly. At the result, refrection power relates to measurement distance and weather, and environmental situation. Finally, it is concluded that method of sensing technology for the condition of forward road surface was constructed by thinking of variation in factor of refrection power.

View full abstract

To reduce the number of traffic accidents caused by older drivers, driver safety coaching system has little effect since the characteristics of this group of drivers are different from other groups and difficult to analyze objectively. This report proposes a new driving coaching system based on the assumption that recognition characteristics of older drivers are related to their physical characteristics. Recognition characteristics of both physical and driving aspects are investigated from several questionnaire surveys followed by experiments using a driving simulator and carrying out a number of physical tests. This paper is specially focused on older driver's visual behavior depending of driving conditions, i.e., on straight road, on intersection point and turning road. This paper reveals some interesting information and understandings; based on them a new safety drive coaching system for older drivers will be purposed and projected in the next step of this research.

View full abstract

The visibility and the legibility of the traffic sign are influenced by illumination and contrast of the sign. Aiming at the establishment of the optical design method of the sign, we investigate legibility by the combination of illumination and contrast. First the complexity of the Chinese character was evaluated by the spatial frequencies. Next, experimental sign was examined as imitating the real traffic sign. The visibility and the legibility of the sign was investigated by displaying the character classified by the derived evaluation method. As the result, a preferable combination of illumination and contrast was shown for all age subjects.

View full abstract

This paper deals with sensing technology of forward road conditions as information to drivers and/or as information for vehicle control. For the sensing, possibility of using CCD cameras for recognition of immediate forward road conditions is examined. We examined the possibility of using CCD cameras for recognition of immediate road conditions ahead. First we carried out experiment of stationary measurement to determine whether the texture of the road surface was able to be recognized by image processing. As a result, the frequency band for the intended texture of the road is distinguished by the spatial frequency analysis of the radiance value. Finally, it is found that this method is one of the higher possibilities for recognizing road conditions ahead.

View full abstract

Japan has already become aged society, rate of aged person 65+ is now exceed 20%. Problem on traffic accidents concerning older drivers is increasing. Especially, in case of person 75+, dementia characteristics may have great effect on driving. Although medical check system for dementia is established, check method for driving has not yet existed. The authors examined relationship between driving performance and cognitive performance using drunken condition. Indicators for judgment driving competence is newly proposed.

View full abstract

Recently, it seems that the public transportation facility's designs are required to take the idea of universal design into consideration. This demand is getting stronger and stronger as the Japan's population grows older. In this study, the authors give eyes to a railway station as one of the most popular public transportation facilities, and wish to develop a designing method concerning the idea of universal design to reduce physical workload when people use it. In order to achieve this purpose, we think it important to evaluate designs quantitatively, not subjectively. We tried to evaluate the workload of walking upstairs and downstairs, which is supposed to give people the highest workload in the body movement performed in a station, by EMG of the legs. To quantify the workloads, we measured EMGs of pretibial muscle, gastrocnemial muscle, rectus femoris muscle, and biceps femoris muscle, and ground reaction. We also evaluated the effects of handrails for elderly people by calculating indexes from EMGs.

View full abstract

The purpose of this study is to construct route advice systems for people who often lose their way. We think that people who often lose their way can't get and make good use of information which used for navigating to a destination. To know what information people get and how use it when they navigate to a destination indoors, we analyzed the eye fixation behavior, the cognitive map, and interviews. And we characterized people who often lose their way. We suggested the route advice system which provides useful information for users and we examined whether it works well or not.

View full abstract

Evacuation from transportation facilities should be effective for all passengers, including disabled persons and aged persons. It is therefore important to develop methods which can evaluate the effectiveness and safety of evacuating those kinds of persons. One way to evaluate safety is via an evacuation simulation. We have developed an evacuation simulation program for passenger ships. It uses a multi-agent method and treats evacuees, including disabled persons and aged persons, individually. On any passenger ships, escape routes are usually pre-designated. Crew members have been trained according to a prepared plan. However, effective escape route arrangements could be changed by evacuees' characters. This evacuation simulation program demonstrates effective escape route options under a range of conditions. We discuss escape route arrangements for aged persons via the evacuation simulation.

View full abstract

Utilizing a proper information service system activates to take barrier-free passenger ships. It contributes to every passenger, including disabled persons and aged persons. Especially they need a more suitable information system, which is used all the way from a passenger terminal to a ship. We propose a simple information service system for a passenger ship to realize the concept. As the system uses commercialized wireless LAN equipment, it can be constructed at reasonable cost.

View full abstract

A small active seat suspension has been designed and manufactured for a one-seat electric vehicle. Our aim was to develop a vibration-isolation system for the driver's seat suspension using active control. However, the evaluation of ride comfort during the electric vehicle running has depended on subjective judgement by drivers. Thus, it is necessary to evaluate the correlation of subjective judgement with objective judgement according to physical values, i.e., vibrations. In this study, ride comfort ratings evaluated subjectively by the "Paired Comparison Method" were compared with the measured acceleration of the seat surface. As a result, we confirmed a good correlation between the subjective judgement and the physical values.

View full abstract

It has been required to improve the usability of railway vehicles by using universal design concept. However, in the case of railway vehicles, there is no quantitative method to evaluate the degree of for universal design. Therefore, universal design 7+1 philosophies for railway vehicles have been defined by analyzing approximately 4000 complain of railway users. Moreover, its checklist has been developed. Using the 7+1 philosophies and its checklist, it has been confirmed to evaluate quantitatively the degree of universal design of railway commuter vehicles on a seven-axis radar chart.

View full abstract

East Japan Railway Company and Hitachi has been working to develop railcars that have lower environmental impact. We have developed the world's first prototype of a hybrid electric-diesel railcar, called the "NE Train (New Energy Train)" and we are checking performance of the hybrid system and railcar on test runs since May 2003. In 2004, we have improved the NE train based on the results of the test run in 2003. With refined longer life and higher power density batteries, we have obtained high acceleration and stopped idling of engine while running. We changed rotation speed of the diesel engine to reduce fuel consumption based on the data of test runs. And we have reduced car oscillation at stopping engine by braking with the generator. After the improvement of the NE Train, through the test run about 12,000km, we confirmed reduction of fuel consumption maximum 20%, reduction of pollutions, improved driving performances same as electric multiple units, and saving of labor for maintenance.

View full abstract

East Japan Railway Company and Hitachi have been developing new energy propulsion system using energy strage technology from the first year of 21th century. The system was elavuated by taking on NE train, prototype vehicle aiming at energy saving effect and environment friendliness. In this paper, we will introduce additional two controls, 'Idle stop control in running condition' and 'Engine stopping control', based on its test run results.

View full abstract

In order to achieve the target of 6% reduction of the output of carbon dioxide (CO_2) which is agreed in the Kyoto Protocol, the Japanese companies have been actively implementing necessary measures to reduce the amount of carbon dioxide generated from logistics activities. It is necessary to establish a quantitative calculation method to verify the extent of achievement. This paper outlines the current status and challenges of the method, and shows its prospects.

View full abstract

An airship-type 1-ton crane robot (hereafter called CraneRobo) is a new concept of a VTOL (Vertical Take-Off & Landing) vehicle driven by cycloidal propeller systems and has safe and excellent hovering characteristics compared to helicopters. The cycloidal propeller system, one of horizontal rotary wings, offers very good thrust vs. input power ratios, and a unique ability to change thrust vectors almost instantaneously. A trial design of a UAV (Unmanned Aerial Vehicle) CraneRobo by cycloidal propellers presented high enhancement of the vehicle's kinematics. The proposed CraneRobo is aiming at transport of 1-ton payload by total power of 320kW. The propeller radius, wing chord, wing span and number of blades were chosen respectively as 1m, 0.4m, 2m and 7units. Four assemblies of the propeller are mounted on a gondola under the vehicle hull. The vehicle will be 23m long with 12m max. diameter.

View full abstract

Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of bogie trucks, because the curving performances of bogie truck depend much on the friction characteristics. On the viewpoint, authors have proposed an original method, "Friction Control", which utilizes friction modifier (KELTRACK^<TM> HPF) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics are able to be controlled as expected. And as the result, curving performances of bogie truck, e.g. decrease of lateral force and flange contact noise, prevention of occurrence of corrugation and so on, are improved drastically. In this paper, results of fundamental researches are reported which play an important role to realize the new method.

View full abstract

It is of great importance to understand the vehicle/track interaction excited by a vehicle negotiating sharp curves when analyzing vehicle stability and material integrity such as wheel flange and rail gauge face wear. The angle of attack and lateral force interacting between wheel and rail have been particularly focused on as parameters governing vehicle/track interaction. In this study, track site measurements were carried out in sharp curves at a test track and in operational sections of a revenue railway line to investigate the effect of lubrication on vehicle/track interaction. Also, the adequacy of vehicle dynamics simulation model was evaluated by comparing with track site measurements to estimate the effect of lubrication on vehicle/track interaction under various vehicle and track conditions. As a result, the lateral force and angle of attack estimated by the simulation model were agreed upon very much by those measured at track site. This paper describes the detailed setup and results of track site measurements and the possibility of vehicle dynamics simulation model to investigate the effect of lubrication on vehicle/track interaction.

View full abstract

This paper deals with the experimental study of the growing process of the corrugation on a flexible truck. The flexible track/wheel corrugation simulator was made in the laboratory. A rolling wheel driven with constant velocity runs around on the track. From an experiment results it is clarified that the wave length of the corrugation with the natural frequency of the system depends on the position of the disturbance on the track. It is also pointed out that the contact rigidity, flexible track and a little slip should be considered as the main factor of the corrugation development.

View full abstract

In this paper, from a view point of multibody dynamics, the modeling and the formulation for development of corrugation on the elastic rail under the motion of wheel with contact rigidity is proposed. The formulation for the rail motion is completed by A.N.C.F. We discuss about the effect of contact rigidity and elastic support on the contact force fluctuation. It is confirmed that the contact rigidity and the elastic support influence on the vibration mode of this system. This leads the fundamental knowledge of the prevention of the corrugation development.

View full abstract