This Paper describes a study on preservation and creation of knowledge about three topics from author's works on railway vehicles. The first topic of research and development (R&D) of universal designed(UD) handrail shows that the activity of R&D is equivalent to creation of knowledge. The second topic of industrial heritage shows the preservation of products including the relevant knowledge. The last topic of derailment monitoring shows the importance to learn from past typical failures and accidents and the concept of disaster risk reduction (DRR). In order to create knowledge from preserved one, it is necessary to abstract the highly generalized knowledge and to concretize the solution available for own task.

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MIT Project and Taxi Project in Japan where I was involved are introduced. Japanese Automobile industries deployed in USA through 1980s are also introduced. My current researches are shortly touched.

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Are there any indices to judge the degree of stability of vehicle in real time? The absence of the index can be one of reasons that vehicle dynamics is difficult to understand for common people. The absence of the index causes that reference models are currently used in many vehicle dynamics control systems in order to judge the states of stability in real time. However, there seems to be problems in the reference models regarding friction change of road surface unlike aircrafts. This paper challenges the above issue. Vehicle motion consists of the element of steering angle, front and rear slip angles. It is shown that the variable β_f-β_r which is taken element of steering angle out of yaw velocity is the effective index in expressing vehicle stability. A direct index which can be used for evaluating vehicles motion is found using a diagram of β_f-β_r and lateral acceleration. The index is valid in all condition including transient and non-liner state.

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An elevator is an important transportation device. Recently, due to downsizing and weight saving of traction machine, the magnetic flux density increases and stiffness of the structure decreases. Therefore, vibration of traction machine may propagate to near-by room and produce acoustic noise and vibration in the room. If in design phase, whole simulation of vibration and acoustic noise from the motor to the room is performed, reduction measures are provided effectively at noise source, propagation path and noise radiation points. In this paper, the comparison and examination result on the cooperation analysis of the electromagnet, structure and noise for predicting room noise and measurement are reported.

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There are some operations in which workers need to approach the hazardous areas near s machine for trouble-shooting, maintenance, etc., while the machine is in motion, which is called as "hazardous point nearby operations." Many risks exist when multiple workers operate in an extensive area, such as a large-scale manufacturing line, where work space often overlaps with the space held by movable mechanical equipment. In a worksite, even when a worker has entered a hazardous area, a third person may start mechanical equipment and an occupational accident may occur due to improper management or a dead angle arising from layout of the equipment. In order to prevent such accidents, workers' qualifications and a task's conditions must be confirmed, and workers' locations must be appropriately monitored. The aim of this study is to propose risk reduction measures using supporting protective device, in which radio frequency identification (RFID) is used in combination with a camera. The proposed measures do not rely only on worker attentiveness. In this study, a model line was manufactured, in which a transportation system and a press machine were arranged, to evaluate the effects of the proposed risk reduction measures. Consequently, the occurrence probability of occupational accidents may be dramatically reduced.

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In this study, we applied a simplified FE analysis modeling technique of bolted joints to aluminium lockbolted joints. Specifically, we set the equivalent compressive areas around the lockbolt on the lapped plates and connected the nodes in this area to the beam element which modeled the lockbolt by using constraint equations. On the other hand, to verify the analysis accuracy, we measured the stress distribution of the lockbolted joints by strain gauges under the static load test. As a result, the stress distribution in FE analysis matched well the experimental results. By using this modeling method, we can estimate the stress distribution of the lockbolted joints with high accuracy.

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In this paper, railway vehicle comfort can be evaluated in numerically by real vehicle's acceleration data, a subjective way and an objective way. The subjective way to evaluate the riding comfort is done by pressing a switch when a subject feels bad riding comfort and a questionnaire survey. In contrast, riding comfort can be also evaluated by objective way based on the movement of subject's center of gravity. Moreover, inertial force makes passengers swing when a vehicle accelerates. In other words, acceleration affects his/her balance. So we can know human's vibrational property by comparing with railway vehicle acceleration's vibrational property. As the result, we describe riding comfort by linking vehicle's running acceleration, jerk and the amount of movement of center of gravity.

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A vibration reduction device for railway vehicles utilizing the vibration of torus shaped elastic body as a dynamic vibration absorber (DVA) was proposed in the previous study. In this study the authors analyzed the vibration property of such an elastic body by the finite element method (FEM). Then a new torus shape elastic body was designed by the FEM model and was actually created. In addition, a FEM simulation model of railway vehicle carbody combined with the torus model was developed, and the combined model predicted the vibration reduction effect. Excitation tests for an actual railway vehicle carbody were conducted, and the DVA effect by the elastic tori against the vibration of the carbody was confirmed successfully.

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In this study, it was intended to grasp quantitatively relationship between load-deflection characteristics and comfort in the cushion of railway vehicle seat. Therefore, sensory evaluation test of comfort was subjected by using several kinds of cushion that load-deflection characteristics are different but shapes are same. As a result, it was found that there is relationship to load-deflection characteristics and comfort of cushion, and it is desirable for determination of hardness of the cushion to be based on a feeling of hardness.

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It is investigated that the weld of flame-resistance magnesium alloy by FSW, and discussed about influence of the joint speed, evaluation of tensile stress and mechanism of the changing of grain size. With the welding of flame resistance magnesium alloy by FSW, joint speed of 5-15mm/s was possible. In addition, tensile strength of the joint specimen is more than 80% for parent materials by reduction of grain size in SZ part. It is thought that reduction of grain size was influenced by twin deformation during FSW.

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Recently, the elastic vibration of a railway carbody becomes larger due to speed increase and weight saving. This vibration causes deterioration of riding comfort of train. Therefore it is necessary to suppress the elastic vibration in the design stage. But vibration analysis of the railway carbody using FEM requires long computation time. This paper suggests vibration analysis method for the railway carbody using transfer matrix method and building block approach that require less calculation load. In order to verify the validity of the simulation results, the experiment is conducted for a small railway model. Finally the experimental results of frequency response functions, natural frequencies and modes are compared to simulation results.

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With speedup of Shinkansen vehicles, noise in driver's cab will increased as well as that of the passenger room. We have tried to mitigate the increase of interior noise by developing various measures. However, the measures developed for interior noise cannot be used for noise reduction in the cab because structural and acoustical conditions are different between the passenger room and the cab. We studied on noise reduction measures that are effective to the cab by comparing the conditions of the passenger room and those of the cab. As a result, we got the possibility that the cab noise become near to the level of the passenger room noise.

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Silence in the interior of a vehicle is indispensable for a passenger taking a Shinkansen vehicle to have a comfortable time. However, in JR East, since we are working for the further speed up of Shinkansen, the silence in the interior of a vehicle is declining with further speed up and interior noise tends to be increasing. Therefore, many measures have been taken to reduce the interior noise for keeping the silence in the interior of a vehicle. In this study, representative measures, after classified to each cause of the interior noise, are introduced, which are selected by usefulness of the developments produced by JR East to reduce the interior noise in Shinkansen vehicles.

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To enhance the safety and reliability of railway transportation, it is one of the most important tasks to check the track condition frequently and accurately. This paper describes the track condition monitoring technique using car-body motions at speed changing section. In an inverse problem to estimate track geometry from car-body acceleration and pitching rate measured by in-service vehicle, time-varying Karman filter were applied. Study result confirmed that proposed solutions can be used to estimate track geometry in level with desired precision, even if the vehicle speed is changed.

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This study considers high-speed train nose shapes which satisfy multiple aerodynamic characteristics. Aerodynamic drag, pressure variation around the nose which effects on an oncoming train and aerodynamic yawing moment of the tail car which causes a flow-induced train vibration in tunnels are estimated by wind tunnel experiments. We examined four types of nose shape as follows: 1) two-dimensional type, 2) straight top surface type, 3) parabolic top surface type, and 4) straight side surface type. The result shows the two-dimensional type is the best among them in almost all aspects.

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Trajectory-based Operation (TBO) is expected to achieve an efficient and orderly air traffic flow. In this paper, inflow and outflow airplanes to the controlled airspace are focused on and delay of flights arriving at Haneda Airport was investigated using CARATS Open Data. According to the increase in the retaining aircraft in the enroute airspace, elapsed time of each flight demonstrates the tendency to be increased. The delay is in the order of 5 to 10 minutes, which is larger than the uncertainty of flight time estimation using meteorological forecast data. Each flight is demonstrated by position versus time plot, and the plot demonstrates the delay by radar vector when the time interval between forgoing and following aircraft is short. The variation of departure time demonstrates the tendency that variation is small in the morning and becomes large in the evening.

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This paper describes the theoretical investigation to develop the element model which is needed to model in applying the physical function model, and to solve the problem concerning the mechanical vibration problem. The element model is a three dimensional basic element with which both ends have mass, and it connects between two mass with a flexible beam which is comprised of spring and dumper. We have applied to a new model of three dimensional human body that the evaluation of ride comfort is able to estimate. The model of human body consists of ten parts: the head, body, right and left thigh, right and left shin, right and left upper arm and fore arm. Each part of the human body is composed with the same fundamental element which is developed in this study. The model is the one that two mass is connected with a flexible bar that has the coefficient of spring, dumper, and plasticity. The movement of the model is considered in three dimensional direction and rotational movement at the point of center. Each part of three dimensional basic element model has different parameters and is connected by joints to compose human body. The analytical result is compared with the measurement result and it agreed extremely well. Some results are presented in the form of parametric graphs. It is shown that the newly developed model with flexible beam with mass at both ends is able to apply in modeling of three dimensional human body.

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Recently, increasing numbers of very small-sized vehicles like a personal mobility have been developed. As the mass of such small-sized vehicle is often comparable to that of their drivers, the coupling behavior between them is increasing in comparison with traditional vehicle types. Therefore, when developing small-sized vehicles, it is necessary to give ample consideration to the dynamics of the human body riding inside them. In this research, a model of a human body inside a small-sized personal vehicle is proposed. However, attempting to implement a whole body model would necessitate dealing with multiple degrees of freedom and give rise to distracting phenomena. Furthermore, the influences of human motion are uncertain and difficult to set into parameters. Accordingly, in this research, the human model is limited to the head and trunk of a human body riding inside a vehicle, and numerical simulations were used to investigate conditions that exist when lateral acceleration is applied. Then the parameters of numerical simulation is identified by Genetic Algorithm (GA). Additionally, the effect of motion control model is considered.

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We have developed the world's fastest elevator at a speed of 1200m/min. Safety gears are important devices in the speedup. The safety gears stop the car at the time of emergency by pushing brake wedges to guide rails. A huge amount of frictional heat between brake wedges and guide rails is generated by the speedup, and the surface temperature of guide rails rises. By the temperature rise, the coefficient of friction becomes small, and braking forces decrease. To solve this problem, we developed an analysis technology to estimate the coefficient of friction drop by the temperature rise. It is clear that the drop of the coefficient of friction can be suppressed by dividing a bake wedge into two, and putting the moderate interval between two brake wedges. We show by a drop test that we were able to stop the lift in the deceleration according to design, and that the average deceleration is within a range set by European Norm.

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An active control system which consists of four active roller guides and four triaxial acceleration sensors, has been developed to suppress the translational vibrations and rotational vibrations of a car. It is necessary for the new system to have a simplified controller system because it has many actuators and sensors. Then the control system is composed of two controllers. One is the controller for suppressing vibrations in the forward and backward direction, and the other is for suppressing vibrations in the right and left direction. By this method, the size of controller system is reduced by 45%. The experimental results show that the proposed system has the ability to suppress the translational vibrations and rotational vibrations.

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It is necessary to reduce the internal noise of a car for passengers comfort, because the internal noise becomes larger according to the increase of an elevator running speed. The aerodynamic noise that is one of the sound sources becomes dominant for the ultra-high-speed elevator. In this study, two types of the streamlined fairing are examined in order to reduce aerodynamic noise by computational fluid dynamics (CFD) and wind tunnel test. It is found that the streamlined fairing which has a curved surface toward the door (front) side of the car is effective to reduce the surface pressure fluctuations. The developed fairing reduces 7.2dB aerodynamic noise compared with the conventional elevator car in the wind tunnel test. As a result of the CFD and the wind tunnel test, we get a prospect of reducing 10dB in the car by the developed fairing.

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Various studies have addressed the shimmy in the vibration that occurs in vehicles. Simulation models of the vibration have been constructed. However, since these models fail to quantitatively describe the mode, we experimentally elucidated shimmy to know its outline. From our results, we constructed a new steering system model with dry friction and lateral rigidity of front suspension and confirmed the influences of various factors. At next step, we constructed the model which increased the degree of freedom.

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There have been few studies of vehicle controllability on a snow road surface of small slip angle. In this report, the objective evaluation indices of tire are proposed as the index of vehicle controllability on a snow road of small slip angle. The indicators consist of multiple tire contact area characteristics including pressure distribution and tread rubber viscoelasticity characteristic. The combination of those indices has better correlation to the handling performance on snow than conventional indices. The effectiveness of the proposed indicators is verified by comparison with subjective evaluation results of vehicle driving behaviors on a snow road.

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G-G diagram is used as a graphic method of steady turning limit characteristics during the longitudinal acceleration. The envelope of the G-G diagram is treated as one curve in general. In this paper, however, two curves instead of the envelope show maximum lateral acceleration in a quasi-steady state turning whether spin or plow in the maximum lateral acceleration, and the transient maximum lateral acceleration. Furthermore influences of vehicle parameters on limit cornering are illustrated.

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New approach to understanding the dynamic energy change index (D^.E) of the steering system as an analogy of the Enthalpy of thermodynamics are studied in this paper. Dynamic energy change (D^.E) is an index of the interaction of driver's control maneuvers and the vehicle behavior. The Enthalpy is addition of internal energy and the PV work-kinetic energy. The feature in the internal energy is to be able to show the I/O of the mass and the calorie to "Observation system ".It thought the operation movement of the steering wheel to be a molecular motion in equivalence. It is shown that P_0 term of D^.E has the Character similar to internal energy. It becomes possible to extract the driver's steer intention as a result of confirming the phenomenon by the Simulation and the vehicle test.

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When an elevator rope for a high-rise building is forcibly excited by the displacements of the building induced by wind forces and/or by long-period ground motion, rope displacement becomes large even if the ground acceleration and the buildings acceleration is small. In previous paper, when elevator cage is stationary, a new practical method for reducing the rope vibration by using vibration suppressors is proposed for relaxing the restricted elevator operation. The advantage of using the vibration suppressors for reducing the rope lateral vibration is demonstrated through numerical calculation. Further, when center of the rope or 1/N position of the rope is pulled, theoretical solution to the free vibration of the rope with vibration suppressors has been presented. However, when arbitrary position of the rope is pulled, theoretical solution to the free vibration of the rope with vibration suppressors has not yet been obtained. In this paper, a theoretical solution to the free vibration of the rope with one vibration suppressor which located at the center of the rope is presented, when arbitrary position of the rope is pulled. Finite difference analyses of the rope vibration with vibration suppressor are also performed. The calculated results of the finite difference analyses are in fairly good agreement with the calculated results of the theoretical solution.

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Elevator system has various safety devices for safe travel. The overspeed governor is one of the safety devices and connected to the elevator car through governor rope. When it detects the excessive velocity of the car, it stop operation of the elevator. In the case of the governor rope is shaken by car vibration, the circumferential velocity of the governor might become higher than car velocity and then elevator car stops suddenly. In previous study, governor and governor rope were modeled by multibody dynamics and good simulation results were obtained. In this study, traction machine and car were modeled by multibody dynamics in order to improve governor model.

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Elevators have a governor system as a part of an emergency gear system, and the governor system consists of a governor, a tension sheave and a looped governor rope. When the elevator car travels vertically, the tension sheave not only rotates, but also induces its vertical displacement. To evaluate the vertical motion, a multi-DOF model of the governor system is derived. From the simulation model, a simplified 1-DOF model is given to describe the specific sheave's vertical motion. The derived 1-DOF model is validated by experiment results, and we evaluated influence of elevator parameters, such as a sheave weight and a car position, against the sheave's vertical motion.

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Recently, for the long-period ground motions by the Tokai earthquake, the Tonankai earthquake, et al., the safety of Tokaido-Shinkansen becomes a problem. In this paper, Using the analytical model of high-speed moving railway vehicles proposed by Shintani, et al., its dynamic behavior is studied by use of the artificial long-period ground motions and actual ground motion in lateral and vertical directions simultaneously. From the analytical results, some correlation effects between the lateral ground motion and vertical ground motion on the possibility of rollover of the vehicle are shown. Also, it is clear that the possibility of rollover of the vehicle is large for the long-period ground motions used in this study.

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In order to improve the curve negotiation performance and stability at high speeds of railway vehicles, we are developing a practical application of low rigidity and high damping suspension equipped between axle box and truck frame. At the beginning, the effect of the longitudinal damping element on running stability was verified by running tests of a 1/5-scale wheelset, which was elastically supported from the ground, on roller rigs.

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Typically Brake performance of train set is evaluated by length of stopping distance. It is useful by reason of being able to evaluate brake performance include influence of wheel skid and running slope. On the other hand, because of this method is an index for the whole train, it isn't able to obtain information about each car. Accordingly, we devised a new method that estimate brake force by each car, to comprehend more detailed brake performance. The method is based on simplified dynamic model and focuses on coupler force and acceleration. In this paper, we describe about validation of the method by result of a running test.

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The objective of this study is to reduce intersection accidents that are one of the most common type of accidents in Japan. The paper proposes a driver assistance system that stops at the stop line automatically before entering intersection, re-start and autonomous brake with safety confirmation against crossing vehicles. The proposed system is designed based on analysis of driving behavior of expert driver. The system is based on recognition of surroundings by digital map and millimeter wave radar. Millimeter wave radars are used to detect crossing vehicles since they have long detection distance and excellent weather resistant properties. In this report, a tracking algorithm that eliminates millimeter wave radar ghost is also developed. Furthermore, the proposed system was implemented and the effectiveness of the system is examined by performing running test in the test course intersection.

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Pedestrian automatic collision avoidance system that can be run automatic steering and/or automatic braking is examined in this paper. We simulate situation in which pedestrian suddenly walking across a road. As vehicle velocity, time to collision, pedestrian velocity and prediction collision position of a vehicle front part are simulation parameters, avoidance success rate is calculated. Thus, from the calculation results effectiveness of automatic braking added to automatic steering is clarified.

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As one of driver assist systems, there is a variable characteristics steering system that can adapt driver-vehicle performance to optimum condition. This paper proposes variable characteristics steering system with fuzzy gain-switching to improve emergency avoidance performance of an automobile. The validity of the system is shown by conputer simulation.

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Haptic guidance control is useful as a driver assistant system since it can guide the drivers by providing steering torque without imposing much stress on the vision of the drivers. This paper proposes to apply haptic steering to the lane change assistance, where the assistant torque instructs the drivers to choose the target course intuitively. A driving simulator experiment was carried out to evaluate responses of the drivers to the different kinds of assistant steering torques. The experimental results indicate amplitude of the assist torque has much effect on the performance to instruct the lane change.

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Accurate parameters are necessary to accomplish precise driving control of vehicle. Identification of vehicle parameters is important to get accurate parameters because vehicle control is affected by the vehicle parameters. An identification method is proposed using Dual Kalman filter algorithm and GPS sensor for the simultaneous estimation of vehicle parameters, i.e. yaw moment of inertia and cornering stiffness. Performance of the proposed identification method is evaluated through examination. Possibility of the proposed identification method is confirmed by examining the estimated results.

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In the aviation industry, microburst wind shear is considered to be a major safety threat, especially in some crucial phases of flight like take-off and landing. Recently, the air speed sensor called airborne Doppler LIDAR (Light Detection and Ranging) which measures the speed of air disturbance even Clear Air Turbulences (CAT) in front of the aircraft is developed. Therefore we design the model predictive flight controller to avoid accidents caused by microburst in the landing configuration assuming the prior turbulence information would be obtained by the LIDAR. To assess the tracking performance of the proposed controller, numerical simulations are carried out, in which the plant uncertainties in the aircraft states and the measurement errors in the prior turbulence information are considered. In addition, the calculation time for the optimization process in model predictive control is examined to confirm that our controller could be utilized in the on-line system.

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A flight controller based on Simple Adaptive Control (SAC) method was implemented to Multi-Purpose Aviation Laboratory MuPAL-α developed by JAXA (Japan Aerospace Exploration Agency) to demonstrate the effectiveness of SAC flight controller in the serious fault case where the longitudinal stability was suddenly reduced in the air. A parallel feed-forward compensator was added to make the whole system meet the ASPR (Almost Strictly Positive Real) condition that is necessary for the plant to be stabilized by the SAC controller. In order to represent the fault case in a real flight test, a "pseudo-fault term" was added to the original controller equipped with MuPAL-α. Through numerical simulations, hardware in the loop tests and flight experiments, it was revealed that the SAC could stabilize the aircraft with such a fatal fault while a conventional PID control system could not stabilize the plane.

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This paper proposes improved estimation methods of dead zones of control inputs used for yaw rate regulation when disturbances are applied to helicopters which lose tail rotors and conduct auto-rotation flights. The proposed method is based on the nonlinear extended Kalman filter which enables simultaneous estimation of dead zones and a yaw moment external disturbance by using a rotational speed of a main rotor in addition to a yaw rate for measurement updates of the estimator. In this paper, the newly developed main rotor brake unit is introduced, algorithms and design methods of the improved dead-zone estimator are described, and then the proposed method is validated by several simulation results.

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Tower Control operation in the airport is handled by Air Traffic Controllers or similar type operators. Mainly, they manage the safety condition and situation by using various information through their eyes. However, sometimes condition would be severe by bad weather or time condition such as sunrise, sunset and night. Visual systems such as Computer Vision (CV), Augmented Reality (AR) can be a support technology to improve their operation under the severe visual condition. We introduce the research of remote tower concept which is advanced air traffic tower control by using AR systems as a new research orientation of support technology for the future work of Air Traffic Control Systems.

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