Since the establishment of the Shinkansen Speed-up Project in 2002, JR East has been developing various technologies seeking for world top level Shinkansen not only in operating speed but also in safety, environmental friendliness and riding quality. In this project, JR East has developed two high speed experimental train sets, Fastech360S and Fastech360Z. The technological target of Fastech360 is to realize 360km/h commercial operation. After a 2-year test running of them, JR East decided to increase the maximum operation speed of Tohoku Shinkansen from 275km/h to 320km/h. This paper describes the overview of the R&D project and the developed technologies, and the subjects to be solved for further speedup for the future as well.

View full abstract

This paper describes a HILS (Hardware-In-the-Loop-Simulation) system for railway vehicles. HILS is a kind of hybrid simulation system, which works in cooperation with hardware test plants and software simulators. The system is most likely to replace most part of running tests of the railway vehicles, and it has a great possibility to make efficient developing of railway vehicles. RTRI is performing a project of developing the HILS system for railway vehicle since 2005. The outline of the system is shown in the paper.

View full abstract

In these days, not only braking performance but also comfort of passengers is required for the brake system of automobiles. Squeal noise of a disk brake system is one of the major problems for comfort. Many studies have conducted about brake squeal, but it has not yet been clarified with analytical solution. Squeal is random phenomenon and lacks repeatability, so making analytical model of brake squeal is very hard. In the previous study, simple model for brake squeal was proposed and strategies for reducing squeal noise of disk brake were investigated by simulation analysis. In this paper, simple experimental setup was made and the effectiveness of above strategies was inspected.

View full abstract

In recent years, it is important to decreasing the railway noise. In the railway noise, there are rolling noise, motor noise, and aerodynamic sound. At the low-speed train, the rolling noise is one of major source of the railway noise. But it is not clear the noise generating mechanism. In the recent research, it is estimated the rolling noise of wheel by using vibro-acoustic interaction analysis. However, it is very difficult to estimate the noise property of the only wheel. In this paper, we describe the estimation of the rolling noise property using the rolling test machine establishment of vibro-acoustic analysis using finite elements analysis and boundary elements analysis.

View full abstract

The purpose of this paper is to obtain the optimal helicopter flight trajectories for reducing ground noise in the landing approach and to conduct flight experiments to confirm the effectiveness of the optimal solutions. We first build a noise model, and then define optimal control problems in order to minimize the noise levels measured at points on the ground surface for some flight constraints. The obtained optimal flights avoid the flight path angle that generates a great deal of noise and skirt the measurement points; these optimal flights are different from the conventional flight. Finally, we verify the validity of the optimal flight patterns by means of flight experiments with an experimental JAXA (Japan Aerospace Exploration Agency) helicopter. The actual flights following the optimal flights also result in noise reduction, and as a result, the study proves the effectiveness of the optimization.

View full abstract

The sum of the structural kinetic energy and acoustic power is a reasonable error criterion to control both vibration and sound. The orthogonal contributor to this error criterion, vibroacoustic mode, has been formulated by the authors. Modal filter for the vibroacoustic mode is frequency dependent spatial filter, and thus its implementation is not very easy. The frequency dependence of the modal filter should be omitted to facilitate its implementation, if the omission is permissible. Weighting filter, which gives added weight to each vibroacoustic mode on the basis of its contribution to the error criterion, is frequency dependent filter. The frequency dependence of the weighting filter holds the key of order reduction on the basis of the vibroacoustic mode. In this paper, the frequency characteristics of the modal filter and weighting filter are investigated through the theory and numerical simulations.

View full abstract

Arc profiled wheels are now employed even in the high-speed trains to prevent unfavorable wear of wheel profile. However, the arc profiled wheel tends to increase the running vibration. Therefore, such a wheel profile is desired that the running vibration can be suppressed while the unfavorable wear is reduced. In this study, the genetic algorithm (GA) is applied to the design of profiled wheel tread which is formed from the initial cylindrical shape. Using the wheels with the obtained tread profile by GA, running simulation of a rail vehicle is carried out on a straight track and also on a curved track of 600m radius. In the comparison of the riding quality such as ride comfort and wheel lateral force with those using the existent arc profiled wheel, it is shown that the proposed method for design of wheel profile using GA has a potential to obtain a desired wheel profile.

View full abstract

We have been developing a new concept bogie, namely that for the gauge-changeable train applicable, for both standard gauge 1435mm line and narrow gauge 1067mm line. So this bogie has to have both high running stability at high speed on the standard gauge line and high running performance on curves of the narrow gauge line. This bogie adopts the direct drive motor system to mount a motor directly on the side of a wheel, independent wheel system, and wheel-set steering system. The independent wheel system provides this bogie with a high running stability at high speed with a short wheel base. We tested this bogie on our rolling stock test machine, and confirmed that no stability problems were found at high speed of 500km/h. Also we conducted a high speed performance test at the Transportation Technology Center Inc in Pueblo, Colorado USA, and on the Sanyo Shinkansen line in Japan over 200km/h. This paper discusses high speed performance of this bogie and its construction.

View full abstract

The shape design method presented in this study is based on the knowledge of spatial non-uniformity of the response due to specific areal blockage by the vehicle. The method consists of an efficient numerical prediction of the pressure wave and its implementation into a shape optimization technique. A series of transient finite element flow simulations of the tunnel entry is conducted to collect the information of pressure response of the tunnel. Several suggestions for effective reduction of the pressure gradient are deduced from this information. The pressure wave generated by a train is approximated by a composition of the pressure response of the tunnel incorporated with non-linear correction. The shape optimization also utilizes the variation of the pressure response. The pressure wave generated by the optimized shape is verified by the direct simulation and it exhibits a good reduction of the pressure gradient.

View full abstract

This paper discusses a new simulation analysis method of high-speed railway vehicles that pass through tunnels. Aerodynamic forces in tunnel sections obtained by measurements are used in the multibody vehicle simulation performed by SIMPACK^<TM>. One-car Shinkansen model is developed and track irregularities as well as the elastic support of the rail are considered in the simulation model. The curve passing performance and the ride comfort in tunnel sections are analyzed. The performance of lateral semi-active damper is evaluated using the simulation model developed in this investigation.

View full abstract

Dealing with lightening is required to enable further speed-up and shortening of the arrival time, and the mass under the spring needs to be decreased in Shinkansen Rolling Stock. The increase of brake energy by the speed-up gives damage to the brake disk and brake lining.Therefore, these need a drastic change. So, brake disks made of aluminum metal matrix composite material was developed Full-scale aluminum composite brake disks were made and performance confirmation was done in the running test.

View full abstract

We applied thermography to measure the surface temperature of a brakerotor with highspeed revolution. The ThermoVision SC4000HS camera output 14-bit digital data at rates up to 50 Megapixels per second,yielding 420Hz of 320×256 imagery. As the result,temperature distribution is measured in the brake. The availability of this sensing method for the investigation of thermal phenomena in braking is discussed.

View full abstract

We have applied the transfer matrix method (TMM) to the analysis of three-dimensional elastic vibration problems on a railway carbody. The carbody is modeled as a simply-supported non-circular cylindrical shell without end plates. The shell model is comprises the three main parts; the floor, sides and roof. The effect of rigidity of each part on natural frequencies was examined by the numerical analysis. It was shown that the natural frequencies changed greatly by improving the rigidity of each part. The most effective part was not only the floor part but also the side parts depending on the targeted mode of vibration. Furthermore, we investigated effects of curved surface. The roof part already has high rigidity due to the curvature, and then the improvement of the rigidity of the roof part does not have so much influence on natural frequencies.

View full abstract

In this study, we investigate dynamic interaction between high-speed trains and a floating trackbed system (FTS) using coil springs. FTS is composed of concrete slab supported by coil springs. The trackbed is composed of a rail and a concrete slab, and those are modeled as freely-supported beams in this study. The railcar model in this analysis has 10 D.O.F. and is composed of a rigid carbody supported by springs and dashpots. We consider the vertical vibration and pitching motion of the carbody, and the random irregularities of the track. Dynamic response of the trackbed is analyzed by means of modal analysis using lower 20 modes of vibration. Dynamic interaction between the railcar model and the trackbed is taken into account. We employ parameters of a 10-car train and investigate vibration characteristics of FTS and carbodies for various train speeds and installation intervals of the coil springs numerically. The simulation results indicate the existence of the optimal intervals of the coil springs for the vibration isolation and the riding comfort.

View full abstract

In recent years, several manufacturers have marketed small one or two-seater electric automobiles. We have examined the improvement of ride quality and the reduction of riding fatigue brought about by the active control of the seat suspension of small vehicles such as one-seater electric automobiles. However, the evaluation of ride comfort while the electric vehicle was running has depended on subjective judgement by drivers. Thus, it is necessary to evaluate the correlation of subjective judgement with objective judgement based on physical values. In this study, we performed a sensory evaluation of riding comfort for a small vehicle. In addition, the psychological factors affecting the sensory evaluation value were examined by multivariate analysis using principal component analysis and cluster analysis. As a result, we confirmed aggressiveness influenced the quality of riding comfort, and the factor of aggressiveness that influenced riding comfort was able to be analyzed.

View full abstract

Sensory evaluation of ride on railway vehicle is performed based on international standards such as ISO2631. However, as technologies relating to railway vehicle progress, it is expected that this evaluation would be not enough. The evaluation for sight and sound from ergonomic and psychological perspectives might be needed as well as traditional evaluations from now. Authors focused on the relation between sight and motion of the railway vehicle, and made experiments in sensory evaluation of ride on railway vehicle using simulator, which is efficient in reproducing various situations by which patterns of images and motion are variously combined. In this paper, the way and results of experiment are described.

View full abstract

The Federal Aviation Administration (FAA) established a new category of LSA (Light Sports Aircraft) that will be the base category of PAV (Personal Air Vehicle) in 2004. Infrastructure, license and category are going to prepare at present. in addition, we consider that some progress of airplane is necessary and will be given by robotic technology for aircraft handling. The airplane using robotic technology for PAV was proposed. We indicated the basic design, constructed prototypes of the 3-dimensional transport robot (3DTR) and results of test flights in this paper. The 3DTR is the new aviation device, which has twin turbojet engines with hyper noise reduction system and flexible wing controlled by 2-axis actuator. We constructed 3DTR and succeeded in demonstrating first flight on November 22 in 2005. Market of personal transport by PAV will appear in the near future and we believe that the research of PAV for physical distribution will become one of the important parts in logistics and transport technology.

View full abstract

Following the development of the high power miniature engine, GEN125, Engineering Systems Co. is currently in the process of developing the GEN-H4, a compact, versatile single seat co-axial counter rotating helicopter. With a multitude of possible applications in commercial and recreational uses, goals such as simplified controls, mechanical simplicity, and minimal maintenance has been accomplished in the process of its evolution.

View full abstract

For the realization of the airship of the wood transportation and the relief airship at the time of the natural disaster, we develop the Cycloidal Propeller occurring by a high thrust. We succeeded in the development of the airship (AAR) of the high exercise performance that we was not seen in a conventional airship, to develop a high-performance airship, we improve a body and the propeller. In this time, we raised that the attack angle of wing to 35 degrees and the propeller number of revolutions to 8rps at the maximum with the improvement propeller (KKR). We experimented on a thrust experiment and consumption power. And we improved this time evaluated the thrust improvement.

View full abstract

QTW (Quad Tilt Wing)-UAV (Unmanned Aerial Vehicle) can realize the vertical takeoff and landing, and hovering flight that seems to be the helicopter, and the high cruising speed that seems to be the fixed-wing aircraft by changing an angle of a rotors and wings by using tilt mechanism. We develop the original QTW-UAV, PFCS (Primary Flight Control System) and experimental method for flight test. The result of the flight test shows the proper flight through the helicopter mode to the fixed-wing aircraft mode is realized by using our thought.

View full abstract

This paper describes the development of a green solar powered long endurance UAV. A small solar plane was designed so that everyone can implement and operate by himself. As a result, the span of the solar plane is fixed to 4m, and the designed wing maximizes the endurance of the solar plane. The feasibility of this design is verified by various flight tests performed by a prototype of the solar plane. The solar cells on the main wing of the prototype are flexible amorphous cells of 4% efficiency. The results of the tests demonstrate that the method of this design can be applied to our final aircraft. Finally, the endurance of the designed solar plane were compared with each efficiency of the solar cell. It is found out that the solar plane can fly during the daytime with the solar cell having more than 10% efficiency.

View full abstract

This paper proposes some driver assistance systems with communication to traffic lights. These systems consist of the driver assistance system, traffic lights and communication tool. The driver assistance system uses information from the traffic lights with the state of the signal and time of the cycle. The demand traffic lights systems are also proposed. In addition, a consideration of the configuration and the construction of the experiment systems are explained. Some field experiments were done and the validity of the system was evaluated by elderly drives.

View full abstract

This paper is concerned with the activity pattern for aged drivers. At present, the population of the aged is over 20% in our country. Along with it, the percentage of driver license holder is rapidly increased, and number of traffic accidents by aged person is increased too. Therefore, these are becoming a serious social problem. As one of the remedies, the construction of support systems for aged drivers is needed. Therefore, using person trip survey data, it is important to analyze activity time for not only aged driver but also the other generation. From the results, it is possible that the aged driver's activities at the near future are estimated.

View full abstract

This study evaluates the Steer-By-Wire technology for motorcycles by computer simulation using mutibody-dynamics model. The mathematical model for controller design is identified from simulation results using system identification method. The SBW controller is designed by two-degree-of-freedom controller consists of feedforward and feedback controllers. The feedforward controller is designed by steady inverse model. The feedback controller is designed by Linear Quadratic Gaussian control theory. Simulation results of the SBW control show that the actual rolling angle follows the desired rolling angle intended by the rider. The SBW controller has some robustness in comparison with the Proportional Derivative control.

View full abstract

The motion stability of vehicle depends on yaw-rate and body slip angle, but these variable influences each other. In the previous paper, we proposed decoupling control for yaw-rate and body slip angle for electric vehicle with active steering, and the simulations results showed that the influence of coupling is suppressed by the proposed control method. In this paper, the validity of the proposed methoed is confirmed by fundamental experiment using electric vehicle with active steering and in-wheel motors.

View full abstract

In recent years, the large vehicle such as truck is one of the major transportations, and is expected to play on important role. However, the traffic accident of heavy vehicles is apt to become serious, therefore, in the design of the heavy vehicles, much attention need to be paid on the maneuverability and the stability. The authors propose to apply electromagnetic suspensions to a large vehicle. With electric circuits coupling electromagnetic devices and supplied electric energy, electromagnetic suspensions can increase frame stiffness like a stabilizer then the maneuverability and the stability of the heavy vehicle improve. Dynamicsal motion of the heavy vehicle is modeled as a full-truck model that has electromagnetic suspension. The effect of electromagnetic suspensions on heavy vehicle performances is examined through numerical simulations.

View full abstract