A lubricating oil analyzer to measure ferrous friction powder has been developed and a condition monitoring for driving equipment of railway vehicles using the analyzer has been studied. The lubricating oil analyzer enable us to measure concentration of magnetic particles in lubricants non-destructively through an electromagnetic induction method. The on-site oil measurement using the analyzer has been tested on a diesel engine mounted on diesel railway vehicles, drawing sample oil from oil dipstick port and returning it to oil filler. The monitoring for hydraulic transmission of railway vehicles has been also examined in bench tests, drawing oil from drain port. It has been found that magnetic particles concentration of the transmission oil measured by the developed analyzer is correlated with iron concentration measured by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) method, which are commonly used methods on condition monitoring for driving equipment of railway vehicles. The results also indicate consistent with ferrous particle concentration measured by a portable meter.

Various high-performance structures are ready to fabricate with the advent of the technology for the additive manufacturing. This additive manufacturing technology has a potential to improve manufacturing costs and may help to achieve high-performance aerospace structures. One of application candidates would be a wind tunnel wing model. A wing tunnel model requires sophisticated designs and precise fabrications for accurate experiments, which frequently increase manufacturing cost. In this paper, manufacturing accuracy and aeroelastic characteristics of an additively manufactured wing model are presented. The feasibility of such wings to use in wind tunnel tests is also demonstrated.

Morphing technologies are attracting much attention as breakthrough technologies to improve the performance of aircrafts. Structural designing of morphing wings is one of the important challenges and corrugated panels are regarded as promising candidate materials for morphing wings. In this paper, designs of corrugated morphing wings for drag reduction are studied considering necessary actuation forces. Static aeroelastic models are constructed to assess the aerodynamic performances or deformations of morphing wings, and aeroelastic analyses are performed with multiple parameter settings. An objective function considering the drag coefficient and the necessary actuation force is prepared and the performance of each case is analyzed. Numerical results show that there is a desirable design parameter or actuation when the two evaluation components are considered at the same time.

The mobile μ-tester is a portable instrument to measure coefficient of rolling friction with slip. While it is originally designed for use in measuring wheel treads, it also can measure the top surface of rails by changing attachments. The opportunity for obtaining data from the rail surface is more than that from the wheel treads, because the rail surface is measured easier than the wheel treads. Through our experiences, we have established an operating procedure to measure the rail surface. This paper describes the structure of the mobile μ-tester in measuring the rail surface, the operating procedure and typical measured data obtained from the top surface of the rail with falling-leaves films.

In evaluating the brake feeling of passenger cars, it is known that vehicle postures such as pitching and heave influence other than the relationship between pedal depression force and stroke and deceleration. In this study, we focused on the transitional posture change during braking and conducted an experiment using an active suspension vehicle. As a result of sensory evaluation, it was found that even if the brake performance was not changed at all, it was confirmed that the brake feeling changed only by the difference in the transient posture, and it was not always good to suppress the vibration. In addition, we devised a method to realize the vehicle posture that was highly evaluated in the experiment by transient control of the longitudinal force distribution of the brake, and confirmed the effect in the actual vehicle.

Flexural vibration modes of railway vehicle car bodies around 10 Hz negatively affect ride comfort because humans are sensitive to this frequency range. The purpose of this study is to develop a new vibration reduction device which can reduce some flexural vibration modes. In this paper, we developed a multi-axis dynamic vibration absorber (called MADVA in this report), which consists of a mass, a housing, presser plates, and elastic materials. The multidirectional motion of the mass is expected to reduce three-dimensional flexural vibration modes. The MADVA has a frequency adjustment mechanism for application to various types of car bodies which have different natural frequencies. We conducted excitation tests of the MADVA and confirmed that its vertical and lateral frequencies can be adjusted to dampen the 10 Hz range. Then, we built a numerical model of the MADVA and predicted the vibration reduction effect on a Shinkansen-type test vehicle via the finite element method. Furthermore, we conducted some excitation tests of the MADVA-equipped test vehicle to validate the vibration reduction effect. As a result, we confirmed that two flexural vibration modes of the car body were effectively reduced by the MADVA.

Under vehicle-running condition, not only the running-wind but also the cross-wind affects the pantograph. Coupled wind between the running- and cross-one may cause the significant increase in the lift-force acting on the conventional railway pantograph. To grasp the lift-force characteristics of the pantograph under the cross-wind environment, the wind tunnel tests using the full-scaled pantograph was carried out. To reproduce the roof-top flow under the vehicle-running condition, the yaw and roll angles of the pantograph were varied. The free-stream velocity and the yaw and roll angles of the pantograph defined the test condition reproducing the running condition. To investigate the effect of the pantograph-head shape on the pantograph lift-force, the pantograph-head shape was also employed as the test parameter. First, the discussion was made on the running condition for the pantograph, where the pantograph lift-force takes the largest value with respect to the cross-wind angle. The pantograph lift-force takes the similar trend to the sum of velocity components called the characteristic velocity. Thus, the characteristic velocity may be utilized as the index to determine the aforementioned running condition for the pantograph. Subsequently, the external dimension of the pantograph-head was allocated as the test parameter. Well correlation is found between the pantograph lift-force and the characteristic area rather than the aspect ratio of the pantograph-head. The characteristic area is the bottom area of the pantograph head projected in the free stream direction. The single regression curve can be drawn between the pantograph lift-force coefficient and the characteristic Reynolds number. Those two parameters depend on the characteristic area, so that the characteristic area must dominantly determine the pantograph lift-force.

This paper presents theoretical consideration of a travel route and speed profile while turning at an intersection for autonomous vehicles. The curvature distribution of a travel route is an important physical quantity that generates a traveling track. The formulation and characteristics of transition curves at connection points for a non-interpolation curve, a single clothoid curve, and a multiple clothoid curve are investigated. The physical variable derived from a curvature distribution function is demonstrated, and the features of the three types of transition curves are explained. The integration value of a curvature distribution function represents an azimuthal angle. Therefore, the curvature distribution curve is the velocity of the azimuthal angle. Then, the first-order differential value of the curvature distribution curve is the acceleration of the azimuthal angle, and the second-order differential value of the curvature distribution curve is the jerk of the azimuthal angle. The theoretical equation of a traveling path is derived from the curvature distribution curve of the three types of transition curves, and their characteristics are formulated. Theoretical expressions of a speed profile of a real running vehicle at a traffic intersection are also proposed. Theoretical values agreed well with the measurement results. The validity of the multiple clothoid curve is discussed analytically as compared with the other two cases where it is interpolated by the non-interpolation curve or the single clothoid curve. It was also found that the influence of the multiple clothoid curve on vehicle movement and ride comfort was superior to those of the non-interpolation and single clothoid curve.

The running safety of a railway vehicle against flange-climb derailment is evaluated with the derailment coefficient. Continuous observation of the derailment coefficient during commercial operation has been conducted with the monitoring bogie. However, the critical derailment coefficient is determined by the friction coefficient between the leading outside wheel flange and rail, which changes due to wayside rail lubrications. The present study proposes an estimation method of the friction coefficient of the leading-outside wheel flange utilizing the multibody dynamics simulation. Look-up tables, which show the relationship between the given friction coefficients and the calculated wheel/rail contact forces, are created from the results of simulation in sharp curves. The friction coefficient of the outside wheel can be regressively estimated by inputting the measured contact forces collected with the monitoring bogie into the look-up table. This paper also considers the influence of wheel/rail profiles on the proposed method and presents a modified look-up table made from simulations with the measured wheel/rail worn profiles.

In the automotive market, it is important to ensure safety and reduce traffic accidents. For trailer-towing vehicles it is strongly required to prevent unstable phenomena such as jackknife and rollover. To improve the vehicle/driver stability of a trailer-towing vehicle, a rear steering control method was developed. From the idea of G-Vectoring control and moment plus control, the developed rear control method is composed of front wheel proportional control and lateral jerk based control, to achieve high agility in turn in condition and high stability in turn out condition. First, the proposed method was evaluated through open loop characteristics by numerical simulation. The results were used to consider the impact of the parameters (gain and time constant) used in the control method. Then, the proposed control method was analyzed in highway ramp scenarios. The result was evaluated by vehicle conditions (quantitative evaluation) as well as expert driver comments (qualitative evaluation). Vehicle evaluation insisted that in turn out conditions, the yaw convergence improved, leading to driver assistance in order to correct the vehicle position.

In N700S Shinkansen rolling stock, we achieved weight reduction of the traction system that contributes to make space for new equipment under the floor of the car body. By using the created space, a self-traction battery system was developed in order for the train to propel itself to be prevented from stopping at any tunnels and bridges between Tokyo and Shinosaka in case of power failure of catenary caused by earthquakes and other natural disasters etc. The self-traction battery system was verified by conducting running tests for the future revenue service. In this paper, we introduce the design concept of battery, the entire batter system and the results of running tests.

In recent years, the use of robots is increasing in various fields. With the expansion of the market, robots are required to have unprecedented functions and have increased opportunities to be used by users without specialized knowledge. Whereas, robot operation still requires high expertise and expensive equipment, and cannot be said to be able to cope with recent change of times. Modularization is known to be effective as a method for efficiently operating complicated systems. Modularization is a technique that simplifies a complicated system by subdividing it into elements. When introducing modularization to a robot, handling software becomes an issue. In order to control the robot's operation, a dynamic model of the robot is required. However, the dynamic model of the robot has a complex coupling relationship such as arms and legs, and when the hardware is replaced it was necessary to change the whole-body dynamic model. To solve this problem, we proposed a new concept of concurrent modularization. concurrent modularization is an approach in which dedicated controllers and dynamic models are created in advance and handled as a single module for subdivided hardware such as arms and legs. With this structure, when the hardware is replaced, the software automatically changes to the corresponding one, reducing the burden on the user. In this study to developed hardware that concurrent modularization hardware and software. In addition, describes the results of a demonstration experiment using multi-link robot incorporating concurrent modularization.

Gear case used at a bogie of a rolling stock is an important part and contain a small gear and a large gear that transmit the driving force from a main mortar to wheel. An axle box, which the small gear and the large gear connect to, is hold the gear case with an axle bearing. So, the damage of the axle bearings may affect the running safety of rolling stock. Therefore, the authors fabricate the hanging rubber for gear case incorporating the piezoelectric element as a damage sensor, which can be simply installed and easily detected the damage of the axle bearing of gear case. As the result of rotation test with damaged small gear, it is confirmed that the damage can be detected by electric signal from piezoelectric part.

Railway bogie is a most important device and it is very dangerous if failures occur. Because there is not the thing which can back up it. Based on a past example of bogie damage, the reliability improvement of railway bogie is essential. In late years, monitoring system is introduced to improve reliability of railway bogie. It is attached vibration sensors to each part of bogie, and a trial to detect abnormality from vibration is being conducted. The MEMS-type sensor has superior advantage, such as durability, well productivity, compact, inexpensive, and so on. So in this study, authors installed vibration sensors on bogie frame and built the sensing system to detect behavior and something wrong of railway bogie. Latest MEMS-type sensor is equipped to this system, and vibration data from sensors is obtained by CAN communication. It was started that various data obtainment and analysis.

UAS Traffic Management (UTM) is a flight information sharing service concept based on advanced communication technologies and information technologies. In principal, UTM is an advisory service and UAS operator has a final responsibility of the flight safety. Because of the extremely high traffic densities of UAS in the future over urban area, existing IFR approach, ATC depends on human resource cannot be scaled to. Therefore, VFR like operation is more suitable for UAS, however, flight information sharing must be required to keep situational awareness of the airspace. For this perspective, UTM concept is very important for small UAS traffic management.

In this paper, we reviewed the usability of the narrow track vehicle with a leaning mechanism by using physiological indices. There are many factors in usability, but among them, we focused on the user's satisfaction with the vehicle. An experiment was conducted on the hypothesis that if a subject's satisfaction with the vehicle is reduced by a lean actuator’s behavior, the level of physiological indices indicating the subject’s stress will change in the direction that stress increases. Electrocardiogram (ECG) and Electroencephalography (EEG) were used to assess the satisfaction. From the ECG, the balance between the subject’s sympathetic nerves and the parasympathetic nerves was evaluated using the index called LF/HF. From the EEG, the subject’s psychological stress was assessed by using the ratio of alpha and beta bands. The result of ECG was based on the hypothesis, but for the result of EEG, it was not possible to identify the tendency of the subject to increase their psychological stress by the lean actuator’s behavior. Therefore, it was not possible to estimate the satisfaction with the methods used in this study. We thought that it is necessary to estimate the satisfaction by including subjective assessment while using other methods such as frontal brain asymmetry.

In recent years, automatic driving level 3 has been developed for realization. In this system, the automatic steering system executes the driving task, but the operating authority is transferred to the driver according to the situation. For that purpose, it is important to grasp the driver intention quantitatively, but there is no clear index for grasping the intention at present. Goto et al.'S study (1) shows the possibility of detecting rough intentions by using driving energy change ((DE) ̇). Furthermore, the inertial force that the driver grips the steering is considered to be an expression of the driver's intention to steer the car more actively. We consider a method that can estimate. In addition, by using a cerebral blood flow measurement device in the experiment, the driver's brain activity is confirmed from the cerebral blood flow change, and the steering intention is read from there.

In this paper, in order to evaluate the traffic accident reduction effect by the driving support system, we first constructed a pedestrian agent model that causes unsafe behavior, and made it possible to reproduce a more realistic traffic environment in the simulation. After that, by installing the driving support system in the vehicle, the accident reduction effect due to the presence of the system is evaluated. In addition, the accident reduction effect is evaluated by changing the parameters in the system.

In recent years, there has been a several number of researches in the field of self-driving system using electric wheelchairs. However, in most researches it must need to construct maps in advance for navigation. Therefore, we proposed an automated driving system for mobility scooter without mapping in advance. In this paper, we use semantic segmentation to classify traversable area on forward camera images into three classes based on human’s judgements, and apply the images to the system that can classify them online using SegNet. By matching a classified image and point clouds from the stereo camera and updating the cells of the map using binary bayes filter, it generates a traveling recommendation degree map of road surface for mobility scooter. To navigate the mobility scooter, we use Hybrid-State A* Search to search a drivable route based on the traveling recommendation degree map, and use Dynamic Window Approach to calculate the actions for following the planned path. The experimental results showed that the proposed system achieved autonomous navigation.

Nowadays, for practical use of automated driving of vehicle, various methods have been developed. Some of them need digital map data which includes lane position information. Currently, lane position information data formed sequence of points have errors due to the manually process. The errors affect vehicle stability and lane followability. Toyoguchi constructed the smoothing method of point sequence indicating lane position by target trajectory search to solve this problem. This method searches a target trajectory schematically and performs a driving simulation of tracking the target trajectory. However, this method update target trajectory frequently. That make curvature of target trajectory fluctuate and smoothing is insufficient. Therefore, this study aims to improve the method by new system. One is expectation slope of curvature. It focuses on turning angle of lane position information. The other is determining whether to search. It judge from the relationship between error and growth. The effectiveness of the proposed method is verified by using lane position information data.

In this paper, a numerical integration method for real-time vehicle dynamics analysis with multibody technique is discussed. When the effect of the deformation of a rubber bush is considered in a multibody simulation, the rubber bush is usually defined as a force element with a high-stiffness property. In this case, the multibody vehicle model contains high frequency modes. As a result, the multibody vehicle model requires a small step size for the numerical integration. In this research, the real-time simulation with a multibody vehicle model was realized by the generalized-a scheme, which allows a dissipation of high-frequency modes with keeping the accuracy in low-frequency modes. In order to evaluate the influence of the parameter for the generalized-a scheme on the accuracy of an analysis result, the authors propose to derive a transition matrix from numerical simulation results. In addition, a methodology of choosing the parameter for a real-time simulation is also mentioned. It was confirmed that a stable real-time simulation with multibody vehicle model including the rubber bush properties can be performed with keeping high accuracy for low frequency modes by choosing a proper parameter according to the methodology.

In the development of an automobile, various testing systems with hardware-in-the-loop simulation (HILS) techniques are proposed. The accuracy of an analysis is significant for the HILS system. The purpose of this study is to evaluate the performance of the HILS system with nonlinear elements. In order to clarify the basic concept of the HILS system, a HILS testing machine with a simple hardware configuration was developed. The HILS system was developed in which damper force was measured in the HILS testing machine and included in the real-time simulation. In the evaluation test of the HILS system, a sinusoidal input test was conducted with various conditions. The performance of the HILS system was evaluated by comparing the suspension stroke of the analysis model and the suspension stroke of the testing machine. We evaluated the performance of the HILS system by the validation of the simulation and the HILS test.

The evaluation of passenger comfort and ride quality in railway vehicles is very important in railcar development. There are many studies to reduce vibration and noise inside the railway carbody. In order to reduce the vibration and noise inside the coach, a new structure that consists of an independent interior inside a body structure has been proposed. The new structure is modeled as the railway carbody with independent interior structure. In this paper, experiments are performed to compare with proposed structure and conventional structure using miniature carbody model. Vibration and acoustic characteristics of the structure are evaluated by the result of the experiment. The vibration and sound pressure level of the proposed structure whose inner shell is hung at side walls is found to be smaller than that of the conventional structure. In addition, vibration and acoustic analysis using finite element method is carried out. In order to compare the vibration characteristics of the proposed structure, simulation is performed by changing wire diameter of hangers.