The contact behavior of a wheel and a guard angle with large vibration of track was investigated for conventional lines. The real bogie of a conventional train on the track with guard angle was oscillated by large shaking test facility. It has been confirmed that the plastic deformation of the guard angle can occurs when the contact force between the wheel and the guard angle exceeds about 50 kN. In addition, it has been clarified that the guard angle maintains its design performance against derailment even if it receive short-time impact force such as the case of an earthquake.

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It is important to monitor surface condition between a rail and a wheel when evaluating running safety of a railway vehicle. This paper proposes the method to estimate coefficient of friction between the rail and the wheel from the vertical load and lateral force measured by a PQ wheelset. Yaw angle and lateral displacement are estimated by Kalman filter including two degree of freedom model of the wheelset. The relationship between the friction coefficient and creepage is obtained, which shows the saturated coefficient of friction.

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This paper discusses the simulation for the estimation of multiple effects to prevent traffic accidents by a diffusion of the Advanced Driver Assistance Systems and Automated Vehicles. In order to reproduce realistic mutual interaction, it is important to model the relationship between the driver agent behavior and characteristics of agents such as sexuality, age and personality. The relationship between driver's characteristics and behavior of the drivers was analysed based on data acquired by the experiment. As a result, the rank of the tendency to obey the traffic law apt to affect the travel velocity regardless of experiment conditions. On the other hand, the rank of the driving skill was apt to affect the travel velocity only rush driving condition.

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To reduce traffic accidents further, near-miss incident analysis will bring us good insights on countermeasures. It requires various kinds of automatic classification software to extract useful information and to get scenario understanding from the near-miss incident big data. There are many preceding researches and classification software. Many of them are focusing on the acceleration data near the trigger time. In this paper, we propose a tag set. Every tag of incident data can be extracted by a rather simple classification. The driving pattern tags are got by observing the whole fifteen second interval. The avoidance behavior tags are got by observing the three second interval around the trigger. By combining the driving pattern tags with the avoidance behavior tags, it is demonstrated that the scenario understanding becomes better.

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Under the existing method based on a detailed equation for evaluating the wind speed that can cause a vehicle to overturn, the instantaneous wind velocity at one point is taken into consideration. In this study, we evaluated the results of the calculations of the critical wind speed which were conducted in consideration of the spatial fluctuation of wind speed. In addition, we also evaluated the critical wind speed in accordance with changes in the height of the center of the car body from the ground and the roughness length. As a result of the evaluation, we confirmed that the critical wind speed increases by up to 1.4m/s, provided that the vehicles and railway structures are those assumed in this study.

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This study considers assessment quantities, such as derailment quotient, to evaluate running safety against flange climb derailment in curves of conventional lines. Relationship between derailment quotient and wheel rise of an outer wheel is investigated with data of running tests at low speeds in a test track with sharp curves and some intended track irregularities, which might cause derailment. As a result, a proper filtering of derailment quotient, which corresponds to the change of wheel rise is shown, and further, a new assessment quantity is proposed, which is based on time history of derailment quotient.

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Moving-object tracking (estimating position and velocity of moving objects) is one of the key technologies for autonomous driving systems and driving assistance systems in mobile robotics and vehicle automation domains. To predict the possibility of a future collision, the tracking system has to recognize what objects are as accurately as possible. This paper presents a method for recognizing vehicles (cars and bicyclists) and people using highly-resolved multilayer laser scanner (MLS). Laser-scan data captured by MLS are clustered, and eight features are extracted from each of clustered laser-scan data, such as distance from MLS, velocity, object’s size, number of laser-measurement points, and distribution of the reflection intensities. A multiclass support vector machine is applied to classify cars, bicyclists, and people from the features. The experimental result using data set of “The Stanford Track Collection” showed that the success rate of people and vehicles classification by the proposed method was higher than 95%.

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This paper presents a Kalman-filter-based method of correcting distortion in 3D laser-scan data from in-vehicle multilayer laser scanner. A robot identifies its own 3D pose (position and attitude) in a laser-scan period using the normaldistributions transform (NDT) scan-matching method. Based on the pose information, the robot’s pose is predicted and smoothed in a period shorter than the scan period using Kalman filter under the assumption that the robot moves at nearly constant linear and turning velocities. The predicted and smoothed poses of the robot are applied to map laser-scan data onto a world coordinate frame. Subsequently, the robot again identifies its own 3D pose from the mapped scan data using NDT scan matching. This iterative process enables the robot to correct the distortion of laser-scan data and accurately map the laser-scan data onto the world coordinate frame. Experimental results of SLAM in a road environment show the performance of the proposed method.

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This paper proposes a new trajectory planning method for obstacle avoidance maneuver of an autonomous vehicle. With the extended application of Inverse Dynamics Compensation via Simulation of feedback control systems(IDCS) method, the disturbance rejection feedback control simulation using a nonlinear vehicle model with tire nonlinear characteristics is used to determine the reference trajectory with respect to the repulsive disturbance force of the obstacle.This method provides a feasible trajectory considering vehicle dynamics and the saturation of the control input.In this method, trajectory planning and control input are determined by two independent controllers in the simulation. The effectiveness of the control system design is verified with simulations of an obstacle avoidance maneuver.

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Autonomous vehicle technology is expected to solve several road traffic issues, including reduction of road traffic accidents, relaxation of traffic jams, and movement support for elderly. Therefore, this technology has been receiving increased attention and several relevant experiments have been conducted. An autonomous vehicle algorithm, which is the focus of this study, simulates an expert driver's steer and speed control in detail. This paper describes the development and verification of target trajectory and speed control target calculation. The proposed algorithm consists of a driver model, which considers the risk potential, and a vehicle dynamics. This algorithm was validated through simulations using a vehicle dynamics model with multiple degrees of freedom in consideration of mutual accordance in mixed traffic conditions.

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The steering vibrations include the useful information, such as road condition, for the drivers. Therefore, the various evaluations about relations of the steering vibration characteristics and the road information are carried out. In this paper, the human vibration sensitivities of the steering vibration concerned with the road information were evaluated first. It is clarified that the vibration direction of frequency band more than 20Hz can’t be discriminated and the sensitivity of the vibration power is decrease at an incline of 10dB/dec for frequency. Next, the evaluating method of the steering vibration using the steering simulator was examined based on the human vibration sensitivities. As a result, it was clarified that the steering vibration can be evaluated by the vibration combination of the rotational vibration and the translation vibration more than 20 Hz.

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Some of the steering vibrations as the road information are useful signals for the drivers to acquire road conditions. This paper examined the relations of steering vibration and the road information by using a steering simulator. The actual steering vibration and random excitations were used for this study. It was investigated which frequency components of the actual steering vibration were necessary as the road information. Furthermore, the road information and solid feel of the steering system were investigated by changing the spectrum of balance and the vibration of the frequency of random excitations. Drivers recognized the frequency under about 4 Hz as unnecessary vibration of steering pull, and the frequency over 100 Hz as unnecessary vibration of itch feeling. When the steering amplitude of vibration was in a relation of 10dB/dec. for a frequency, the drivers recognized the road information wealthily and steering stiffness.

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Influence of body stiffness on vehicle maneuverability and handling characteristics has been open problem for decades. This paper focuses on the influence of the high frequency body vibration on human motion sensitivity, and clarifies that the vibration reduction in the 20 Hz band shortens the time to recognize the lateral motion during the minute lane change. Furthermore, we derive sensory quantity of the lateral motion from skin shear displacement on the contact point with sheet back, and clarify the mechanism that "vibration reduction in the 20 Hz band reduces the noise of the sensory quantity of lateral motion and shortens the recognition time of the lateral motion". This shows that "vehicle body vibration characteristics in the 20 Hz band effect vehicle maneuver feeling".

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Passenger’s seats of railway vehicle have important role to provide comfortable transportation. The increase in sitting comfort is directly connected with the increase in the ride comfort of railway vehicle. In order to estimate the comfort of railway vehicle, we focused on the brain activity obtained from optical topography besides questionnaire as a subjective evaluation. We evaluated the sitting comfort of seats of Shinkansen high speed train and express train by using the optical topography under changing the hardness of seat cushion. Although the sympathy obtained from optical topography in case of the short time sitting disagrees with the comfort feelings of good or bad estimated from the questionnaire, the correlation between the sympathy obtained from brain activity extracted from the subjects who can correctly estimate the hardness of seat cushion and the subjective evaluation of a preference was shown. In case of long time sitting, the time series changes of stress brain index are similar to the feelings tendency of subjective evaluation. Further the subjects who have pains in their body always feel high stress under sitting condition.

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Experiments of a model verified that a wing-less aerotrain with brush will be able to have lift force to levitate the body aerodynamically and flies close to the road (track) like an airplane. The speed is 400km/h and weight is less than 1/35 of existing Japanese “Shinkansen”, and the construction cost of track is small. When the area cannot afford cost of Shinkansen, the low cost thinner line by aerotrain will be desired. A line between central Nagano and Kouhu station accessible to Tokyo metropolitan area by coming “Linear Shinkansen” are studied, and the fare will be reasonable using 20-seats aerotrain. Then a Tokyo metropolitan airport access line are studied, and 17 minutes access from Tokyo to Narita with reasonable fare by 50-seats aerotrain, will be feasible. The system is versatile and placed as “the third Shinkansen” to “the Linear Shinkansen” for the heaviest traffic and “the existing Shinkansen” for the heavy traffic.

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The Chiba Experimental Station, part of the institute of Industrial Science of the University of Tokyo, is an important field for the study which required large-scale experimentation. In this paper, history of Chiba Experimental Station and a portion of the mobility research from a number of studies that have been performed in Chiba Experimental Station were introduced. In addition, ITS R&R experimental field with Chiba test Track 2.0, the mobility research field for the transportation and logistics were described.

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In recent years, actual operation of automated truck platoon system in mixed traffic is considered under the limited traffic environment such as an expressway in Japan. As a truck forms a platoon with short gap in this system, the truck platoon may adversely affect a general traffic. A driver of leading truck in platoon manages the safety. It is difficult for a driver to confirm safely of long platoon consisted of three or more heavy-duty trucks. Especially safety confirmation during lane change is difficult. Therefore, this paper proposes a design of HMI system for truck platoon in lane change on an expressway, and evaluate the effectiveness by experiments using driving simulator. In subject experiments using a driving simulator, driving behavior, the biological reaction, and questionnaire are analyzed comprehensively.

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This paper describes an estimation method of ego-vehicle’s position using a 2D map. The general approach for localization is to match the lane lines between the map and the real world. However, such approaches suffer from changing the environmental conditions and painting clearance. If considerable changes occur, the false-detection rate increases due to noises and miss-detected lines. In order to solve this issue, a localization method based on the holistic road area detection is proposed. First, the road area is extracted from a predefined 2D boundary map. Next, the real world road area is detected using LiDAR and converted into the binary image plane. Finally, an image registration technique is applied to calculate the overall matching score of the road area between the map and LiDAR images. The proposed method has provided an accurate estimation against environmental changes with low-cost calculation based on the simulation results. In addition, the validation of the proposed method in the real world has performed less than 0.2m for the estimation error.

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Recently, the technological development of automated driving of automobiles are carried out actively. Cartographic companies are developing high precision 3D maps including traffic lane maps. A traffic lane map consists of sequence of points which is based on lane markings. However, since lane markings are not painted at intersections, traffic lane maps cannot be designed there. The previous study proposed a designing method of path by using arc and straight line, and vehicle driving simulations are employed in order to smooth the curvature change. However, a curvature changes while vibrating. Thus, this study proposes a designing method of lane map at intersections by using clothoid curve. As a result, the virtual traffic lanes can be designed by clothoid curve, and its curvature is expressed without vibration.

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In recent years, research on automatic driving has been actively carried out by nation. In this study, we will conduct esearch on automatic parking control which is one of automatic driving techniques. In the present Japanese housing environment, there is a very small parking lot difficult to park. Therefore, in this study, we consider driving performance improved by adding driving force control to steering control. The purpose is to examine the system which can carry out smooth parking even in various parking areas and to confirm the effectiveness in model vehicles.

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This paper described the examination of the advanced control technology application to the trailer part of a largesize special semi-trailer for the mutual accordance with the tractor equipped with high level ADAS(Advanced Driver Assistance System). The vehicle to study is equipped with the steering system of the trailer axis with an actuator with the high response performance that in recent years supply increases to. We proposed control method to make up for high driving skill required by a driver of the articulated vehicles including the off tracking of the vehicle which became the problem at middle low speed running. Furthermore, we described a vehicle dynamics simulation system for the suggestion of the autonomous driving control system of the trailer vehicle and some evaluations.

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In the development of an automatic driving system of mobility scooters, a traversable area detection method in the range of about 10m where position accuracy can not be guaranteed by GPS is important. We propose a traversable area detection method that can perform advanced traversable area recognition using semantic segmentation. Semantic segmentation classifies images into several meaningful classes on a pixel by pixel basis. Therefore, we make data set classified objects on the forward image into three classes based on the judgment criteria of traveling recommendation, and constructed a system that can classify objects online using SegNet. By matching a classified image with point cloud of a stereo camera and updating a cell of the traversable recommendation degree map by bayesian filter, it is calculated how much traveling is recommended for mobility scooters on road surface. We tested the system in a road scene. As a result, it was found that plausible traversable area can be obtained by the proposed method.

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In the lane recognition system of driving support devices typically known as Lane Keeping Assist System and Lane Keeping System, it is necessary that coordinates of lane markers detected by image processing of forward road image are converted into practical values for steering control, i.e. lateral distance, heading angle to the lane and curvature of the lane. To realize state steering control, the Kalman Filter is widely applied for this conversion process which is called estimation process of lane state. In this paper, in addition to forward lane points usually used for estimation of lane state, backward lane points, which are obtained from vehicle motion without using backward camera are newly introduced as observables of the Kalman Filter. Also, lane shape is approximated by cubic curve to consider clothoid parameter of the lane. Conducting estimation of lane state using the developed Kalman Filter, it is indicated that noises of estimated values are reduced in comparison with estimated values obtained from a previous model without degradation of estimation performance of maximum curvature.

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The Chiba Test Line at the University of Tokyo was newly constructed as the Chiba Test Track 2.0 in March 2017.The performance test of functional paints on track were carried out in order to improve the aesthetics and maintenance performance. The water-base rust prevention paint were used for rust prevention purpose. The heat exchange paint was used for the purpose of suppressing track destruction due to thermal expansion and contraction of the rail. Data acquisition of the initial performance has been completed, and the long-term durability test is currently being executed.

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In improving the collision safety of the train in a level crossing accident, it is important to clarify the relationship between the damage to the occupants in the train and the collision situation. We focused on the number of occupant injuries and organized estimated collision speeds and collision obstacles as to serious level crossing accidents and major level crossing accidents defined in this report from FY 1987 to 2016. As a result, the distribution of estimated collision speeds and the average of speeds estimated in serious level crossing accidents and those in major level crossing accidents coincided with each other irrespective of the number of occupant injuries. As the result of a detailed study on the situation of these accidents, we found that the number of occupant injuries was reduced even at high collision speed in the case of an offset collision. The collision obstacle is mainly a motor truck (nearly 70 percent). Among them, the number of occupant injuries tended to increase when the train collided with a trailer or a dump truck.

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In order to improve running speed at the curving section, tilting control systems have been developed. As the tilting control system, there are the pendulum type and air spring type. In the research field of the tilting control using air springs, there are very few researches of simultaneous control between tilting and vibration. In this research, simultaneous control between tilting and vibration using air springs are aimed. For the simultaneous control, the linear quadratic integral control theory was used.

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The Remote Tower (RT) operation is a future air traffic control concept for airport tower. In the RT concept, operational tower will not exist in the airport. Alternatively, some of fixed cameras make panorama vision and a PTZ camera shows specific view. Moreover, surveillance sensor provides accurate aircraft position and integrates those information on the Augmented panorama display. In this research we developed prototype experimental system. We discuss about some of basic visual technologies and show result of experiment .

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It has been shown that passengers have large reduction effect against elastic vibration of railway vehicle car body. That effect is considered due to viscoelastic motion and multi-directional motion of human body. This study focuses on the latter one and aiming to develop a new vibration reduction device to mimic the multi-directional motion of passenger. In this paper, an experimented multi-directional dynamic vibration absorber (called MDDVA in this report) is developed. The MDDVA consist of a resiliently supported metal ball and elastic balls to support the metal ball bottled in a rigid cylindrical vessel. The metal ball can vibrate multi-directionally in the vessel and is expected to work as a MDDVA. In addition, the natural frequency of the MDDVA can be changed by pressing the elastic balls from the top. To evaluate the effectiveness of the MDDVA, excitation test using a scale model of railway vehicle is conducted. As a result, MDDVA can reduce the elastic vibration by adjusting the natural frequency of MDDVA to that of the scale model, and multi-modal vibration reduction effect is successfully observed. And then, FEM models of the MDDVA and a scale model of railway vehicle are constructed to verify the mechanism of multi-modal vibration reduction. It is confirmed that the multi-directional motion of the metal ball produces the multi-modal vibration reduction effect by FEM analysis.

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Vertical vibrations in railway vehicles are not only induced by vertical track irregularity but also affected by the rotation of wheelsets with small mass imbalance. It is known that the excitation force generated by the rotation of imbalanced wheelsets is transmitted from the bogie to the carbody through longitudinal connecting members such as traction devices and yaw dampers. In this research, we firstly investigated the influence of yaw dampers on the vertical carbody vibration induced by the rotation of imbalanced wheelsets. Vibration measurement tests were performed on the rolling stock testing plant at RTRI using a test vehicle with/without yaw dampers. In cases where there is no yaw damper, the vertical vibration of the carbody was lower than where yaw dampers are equipped. This result indicates that the transmissibility of vibration from the bogie to the carbody through yaw dampers should be reduced. In order to suppress this vibration transmission, we have devised a new mounting structure of yaw dampers and installed it actually in the test vehicle. The new mounting structure of yaw dampers has a moving beam with a linear guide and a restoring spring. The moving beam and yaw damper bracket can be moved in the longitudinal direction to the carbody. This paper reports the results of vibration measurement test conducted by applying the new mounting structure of yaw dampers. As a result, it was confirmed that the longitudinal and vertical carbody vibrations related to the rotation of imbalanced wheelsets were lower than the case of the conventional structure.

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In order to improve the running performance of a railway vehicle, the authors developed the axle box suspension with the magnetic elastomer. The magnetic elastomer is composed of magnetic particles and the elastomer such as synthetic rubber. This material is characterized by its hardness variation depending on the magnetic field. In this paper, the authors synthesized the bimodal magnetic elastomer containing nonmagnetic particles. In a characteristic test, the authors confirmed that Young’s modulus of the magnetic elastomer changed in the range of about 2.2 times depending on the magnetic field. Moreover, the authors carried out a running test on a test line of the MIHARA Test Center. The authors confirmed that the axle box suspension with the magnetic elastomer were able to secure the running stability at 70 km/h without causing an unstable state. In addition, the authors carried out a running test on a test line of the Railway Technical Research Institute. The authors confirmed that the axle box suspension with the magnetic elastomer were able to reduce the outer lateral force of a leading wheelset.

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This paper provides simulation results of carrier swing of a ropeway during passing through a tower. When the ropeway carrier is travelling upward, it suddenly swings backward in a large way during passing through the tower, and collided with the tower. One of the accident causes is pointed out to be wind gust. In this accident, swing characteristics of the ropeway carrier during passing through the tower are essentially needed to gain an understanding of the cause of the accident. This paper describes basic behaviours of carrier swing of the ropeway carrier during passing through the tower. It has its beginning with simulation model on longitudinal carrier swing during passing through the tower. Comparison results between simulation and experiment are also reported for carrier swing during passing through the tower. In addition, simulation results are reported for the effect of damping force of the damping equipment on carrier swing during passing through the tower.

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