This paper gives several points to reduce the environmental load of transportation. First of all, both types of the environmental loads and the neccesity of introducing an evaluation function to discuss the environmental loads are mentioned. Then several points to decrease the environmental loads are discussed mainly focused on the field of transportation. Finally an index instead of the conventional one, to promote the reduction of the environmental loads caused by transportation.

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Author thinks it is undisputed fact that today's automotive is the direct descendant of horse-drawn carriage used in western countries. On the other hand, we had used ox-drawn carriage in our medieval history. Although the knowledge of ox carriage went to oblivion from modern automotive engineer, they themselves had pregnant universe. This paper is one attempt to dig out our lost roots of wheeled vehicle from many aspects; origin, structure and utilization style.

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The target of "Humanoid Robotics Project" (called HRP) is to find some suitable applications for humanoid robots. In the former two years, the platform system (as for common base of R&D) was developed, and in the latter three years, element technologies as for applications was developed. In HRP. KHI developed two models of the remote control system, the super cockpit and the portable remote control device. By using the latter system, the tele-operated humanoid robot succeeded in driving industrial vehicles, which was the first experiment in the world. As the portable remote control device was developed to improve the property of operation, we expect that it would be applied not only to humanoid robots but also to other applications for remote control system.

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This paper describes Transportation Accessibility Improvement Policies in Japan. Three years have passed since Transport Accessibility Improvement Law went into force in 2000. Stations, bus terminals, buses and trains have been becoming accessible recently. But improvement of accessibility is not well fulfilled, as compare to the targets established by the government, which consist of 2010,etc. Recognizing these situations, the government not only continues to give incentives to public transportation operators, but also take community based approaches to support steady improvement of accessibility In addition to these measures, the government is tackling remaining tasks, such as the handle-type electrically-powered wheelchair adapted for the public transportation, audio guide for the visually impaired, etc.

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This study deals with wheel flange climbing, which is noticed after the derailment accident occurred on Hibiya Subway Line. An analytical model of running one-axle truck is built assuming simplified shapes of wheel tread and rail head. Two cases are investigated according to the situation of flange contact. One is the case where wheel flange contacts with rail keeping contact also between wheel tread and rail. The other is the case where wheel beginning to lift and flange climbs on rail. Simulation results are shown for both cases, and the outline of experimental apparatus, which aims to verify the availability of the model, is explained.

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When a compression wave generated by a high speed train entering a tunnel travels through the tunnel and arrives at the tunnel exit, a pressure pulse is radiated from the tunnel exit. The pressure pulse (micro-pressure wave or tunnel sonic boom) is closely related to the form of the compression wave arriving at the tunnel exit. The improvement of the Shinkansen nose shape is one of countermeasures for reducing the micro-pressure wave. This paper describes the optimization of Shinkansen nose shape for a tunnel with a hood by axially symmetric CFD.

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For speed up of Shinkansen, it is important to improve passenger comfort such as noise reduction inside the car. Our targets of internal noise are 65dB(A) on the open section, 70dB(A) in the tunnel section at 360km/h. To achieve these goals, we analyzed high speed test results, confirmed transmitting courses of internal noise, and found that noise from the floor and windows were dominant. In this paper, we report the methods to reduce the noise from windows.

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Electric Vehicles (EVs) have been introduced into the car market but its application has been limited to town use owing to mainly poor battery performance. Superior battery storage energy and power density are required for present systems to be considered for wider range of use. Compared with the well used EV/HEV battery Nickel Metal Hydride and others Lithium-ion battery has superior performance but is only widely used in electrical devices. Lithium-ion battery technology is rarely used in EV/HEVs because of the severe environment of the vehicles. This paper will show the improvements made to overcome this hurdle and present the public road test results of EV propulsion applications of this technology.

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This paper deals with road surface condition sensing technology in order to use the vehicle control on the driver support system. We proposed estimation algorithm of forward road conditions especially friction coefficients of forward road. The amount of reflected rate of Laser Rader was used at forward road sensing. Considering actual traffic, there are situations that a single sensor is difficult to detect road condition. Therefore, this algorithm estimates the friction coefficient of forward road referred the result of road measurement just before tire passes. As a result, the estimate accuracy is enhance by learning the these relation owing to estimate the friction coefficient of several roads.

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The concept on city logistics has been attracting research interests in recent years, where the logistics is affected by the conditions of the city, in particular the traffic situation. So, we propose an unified model of distributed urban traffic control and city logistics. We attempt to extend the self-organizing control of signal network proposed by us, such that a specific traffic path for the logistic activity is effective while maintaining total traffic efficiency in the city. Preliminary simulation results shows that the proposed approach is promising.

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This paper presents estimation of conditions of road surface by using electromagnetic damper, which generates damping force with electric motor/generator. Conditions of road surface are estimated by analyzing the characteristics of generated voltage the electromagnetic damper. Electromagnetic damper can measure vibration of suspension system including vibration of tire. It was shown that there is a correlation between excitation rate on the mode of tire vibration and friction coefficient of road surface for "Smart Roadway".

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This study deals with development of a traffic simulator as an evaluation tool for traffic flow. At first, real traffic flow was measured in urban area, as construction of driver model and the characteristics of real traffic flow were obtained. Next, we constructed the longitudinal traffic simulator which includes dynamic behavior of vehicles, control algorithm of drivers, and traffic environment. Using the results of the measurement of traffic flow, the models with each driver model are described real traffic condition. Finally, it is shown that driver characteristics in traffic flow influence traffic condition.

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This manuscript briefly introduce the Sustainable ITS project recently initiated under Collaborative Research Project with Industries on inter-disciplinary research environment consisting of traffic, automotive, control, computer and communication engineering. The project aims to provide advanced ITS services, to create new ITS industries and to help to achieve liveable societies. The project has a three-layer structure. The first layer is establishment of a mixed reality based transportation space. The second layer is basic research on the human factor using established space, and the third layer is ITS application research utilizing the research results. This paper presents mainly concept of the first layer under construction.

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We design a set of protocol suite for DSRC : Dedicated Short Range Communication System whose wireless bandwidth is allocated for special usage of Road-Vehicle Communication. The Local Port Protocol is designed base on a transaction-oriented protocol and has two layers architecture for the balance of the implementation in low resource on-board equipment and high reliable communication in electric payment. These protocols are fit for DSRC application services such as the parking access control, the probe information and the electric payment. We introduce the probe information services as one of DSRC application services and evaluate the quality of information as traffic information by using traffic simulation.

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At an automated container terminal, it is necessary to give safe and efficient operation management to automatic apparatus. We developed the technology that operation of an actual container yard is able to simulated. It introduces about yard operation management simulation technology utilizable as the determination of an management rule, determination of the number of apparatus and a tool for prior verification of design conditions.

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This study developed a method of evaluating drivers' awareness using Situation Awareness (SA) when driving a vehicle equipped with a low-speed adaptive cruise control system (low-speed ACC). Some experiments using JARI-Driving Simulator were conducted to find out the relationship between SA and drivers' behavior, and to develop indexes which indicate drivers' SA level. The simulator tests showed that a) the use of the system gave a significant effect on the SA for recognizing the movement of other vehicles, whereas b) the participants who are not familiar with the system yielded lower SA level for identifying the current status of the activating system.

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In the research regarding the permissible range of warning error for lane departure warning systems, it is important for examining the safety margin to prevent lane departure and driver's acceptability. In this paper, the permission range for warning error was examined by experimental data and through analyzing the relationship between the occurrence position of warning and driver's perception characteristics. It was shown that driver's perception is related deeply to the occurrence position of warning from the lane marker. And the variance rate of driver's subjective evaluation was in the range of ±15cm around the lane marker center.

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In this study an analysis was presented to the functioning of a low-speed adaptive cruise control system (low-speed ACC). The effects on driver behavior by a low-speed ACC with and without stop control functions were investigated by driving simulator experiments and by collecting actual vehicle data in traffic congestion. ACC without stop control lowered the possibility of colliding with a preceding vehicle in emergency situations. ACC with stop control, however, significantly reduced the driving workload regardless of the traffic environment.

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Aluminum hollow structure is adopted to railway carbodies to improve specific stiffness, but the acoustic transmission loss property of the hollow structure has not been examined in detail. We study the transmission loss with numerical analysis technique, and find out that the transmission loss is worse than the single plate with equivalent mass at the frequency, at which the 1st vibration mode of each plate element separated by rib is excited. This phenomenon occurs to arbitrary cross section structure with rib, therefore it is not easy to simultaneously improve the specific stiffness and the acoustic transmission loss property. We find that the numerical analysis result coincides with experiment data very well.

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The authors propose the concept of "Control Fusion of suspension system". The Control Fusion means the merging of functions of control for suspensions. This study aims for the realization of control of the motion, vibration and rolling using new suspension systems with electro-magnetic devices under control in which the five functions. sensor, actuator, spring, passive damper, and energy regeneration are merged. In addition, the evaluation platform was made and some experimental results of the electro-magnetic device were shown in this paper.

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A self-powered active suspension, which uses energy regenerated by a damper to produce control force and requires no external energy, has been proposed by the authors. However this system needs a generator as well as an actuator and this makes the system complicated. Then the authors propose the system that carries out regeneration and active control with one actuator. The method to accomplish the two functions simultaneously is presented and the energy balance between regenerated and consumed energy is analyzed. The results indicate the proposed system is feasible.

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The authors have been presented the possibility of piezoelectric elements attached on the car body for vibration suppression of railway car body by their previous research. However the strain of car body should be transmitted to the elements effectively and piezoelectric elements should be attached and detached easily in terms of set up and maintenance in practical use. In this study, attachment methods of elements are suggested and the strain analysis of each suggested method is done by FEM. The result shows that the member strains hardly in the method of attaching elements to member shaped C cross section. From this result, method of connecting elements on blocks directly instead of members is investigated with various condition.

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To keep safety of rolling stock running on curve section, it is very important to reduce wheel load variations of bogie truck on the track cant run-off section. In this study, some new devices of primary and secondly suspensions have been developed, then field tests with the truck equipped new devices are carried out. The field test results show the reduction of wheel load variation by 20% from the conventional condition when the rolling stock run at low speed. Also to keep safety even under the air spring puncture condition, new air spring with stopper has been developed, and the wheel load variation under the puncture condition is lower than the maximum load variation for safety.

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This report describes the effect of vertical position of traction links and anti-yaw dampers (traction devices) upon vertical vibration of railway vehicle carbody. In case that the traction devices have offsets from the truck-pitching center, the carbody suffers bending moment through them. Therefore, it is important to decrease such offsets. An objective function concerning strain energies stored in the rubber bushes of traction devices is defined, and the vertical positions of the traction devices are determined to minimize the objective function. By numerical calculation, it is shown that this method is effective to reduce excitation due to truck pitching, especially when the rigidity of traction devices is increased.

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To suppress the vertical vibration of railway carbodies, the authors propose to control the force applied between bogie frames and wheel sets. Actuators are installed parallel to the axle springs in the bogies. The controller to determine the appropriate force generated by each actuator are designed based on the Linear Quadratic Guussian (LQG) theories, and numerical simulations are carried out. The results show that the control method effectively reduce the power spectral density (PSD) of acceleration on the floor.

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By the development of vehicle dynamics and vehicle dynamics control, the vehicle is more safely. Almost the vehicle dynamics model is tested by lane-change. The lane-change is simulated on the straight road. In this paper, the vehicle dynamics model is simulated by the lane-change on the curve road. The vehicle dynamics model is four wheels model with the roll and pitch model. The driver model is simple preview tracking control model.

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This paper is dealing with optimal vehicle trajectories for emergency obstacle avoidance situation. A vehicle trajectory problem is formulated as an optimal control problem that finds the solution that minimize an objective function and satisfies both boundary and path constraints. The objective function consists of tire workload and control effort. A numerical technique called a direct optimization method is used for the optimization of the steering and braking torque command. Optimal usage of control inputs in emergency obstacle avoidance situation is discussed.

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It is seen that the vehicle performance is changed by the difference between seasons or road surface temperature. The authors consider the dependence of tire surface temperature about the tire forces, which is considered as one of the reason of the preceding. The newly developed tire model is consists of two function, the thermodynamic function for predict the tire surface temperature and the force adjusting function for adjusting the tire force with tire surface temperature change. The parameters of this model are identified by the measured data. To validate the accuracy of this model, the simulation results are compared with the experimental results which the rotational angular velocity is changed using the indoor test facility. The simulation results agreed rather well with the experimental results, which proved the appropriateness of the developed model.

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This study proposes a new control system to enhance directional stability of small-scale electric vehicle by Steer-by-Wire (SBW) System. SBW has structure merits in avoiding interference between the driver and steering wheel since mechanical link between steering wheel and tire is replaced by electric wire system, consisting of sensors, steering actuators and controllers. To enhance stability against disturbance, steering control algorithm of SBW is proposed by using theory of disturbance observer. To improve straight-running stability, the controller is designed to regulate the yaw rate generated by asymmetric braking on μ-split road. The effectiveness of the proposed SBW is verified by computer simulation. Finally, the on-board system of experiment vehicle is introduced.

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This paper describes the stability of a tractor-semitrailer combination while braking. We first constructed nonlinear equations of motion for articulated vehicles with 8 degrees of freedom. Secondly, a simulation study was carried out to model vehicle performance in realistic situations. Jackknifing was recreated by simulation under conditions of traveling down a longitudinal road gradient. A study of the load rate of each tire showed that our model accurately describes the mechanism of jackknifing as well as the motion of limit performance conditions. Finally, the relationship between articulated vehicle, road gradient, and limit performance is shown.

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In Japan, there are a lot of earthquakes and many elevated highways in the traffic system that may receive effect from motion of the earthquake. Even though the elevated highways could withstand with earthquake intensity less than 3m/s^2 but the elevated highway will be closed for all vehicles when the earthquake intensity exceeds 0.8m/s^2. The vehicle and the driver's responses during an earthquake have not been elucidated. In this paper, steering operation as one of the driving behaviors is analyzed based on driver's steering energy, which is calculated from angular velocity of the steering wheel and driver's steering torque. The objective of this research is to clarify how and why the driver's steering responses are affected by the earthquake. To achieve this purpose, experiments using driving simulator and computer simulation are carried out. The model for analysis consists of an elevated highway model, a full vehicle model with six degrees-of-freedom, a brush tire model, and a front preview driver model.

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To evaluate the riding comfortability of crawler-type construction machines with bogie mechanism, a simulation analysis method when the machine travels on continuous uneven firm grounds is established and some simulation results are analyzed. On this kind of grounds. loads acting via running equipment from ground are not so large but fluctuate steadily. The bouncing behavior at the driver seat position is investigated. Then the effects of the type of bogie mechanism called K type and X type on the behavior are clarified and discussed quantitatively. The change of the bogie mechanism effectiveness by the bump height and pitch of uneven grounds is also studied.

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Brake noise reduction for a machine-room-less elevator is important for car quietness. Because the traction machine is installed into the elevator shaft, and the elevator car stops near the traction machine. Especially, a new slim gearless PM motor is applied to the traction machine, and it needs more brake force rather than traditional geared motors. Therefore, brake noise reduction is a key technical issue for the machine-room-less elevator development. In this paper, a new brake control method has been proposed. The controller detects current fluctuation caused by the brake arm movement. From the current variation, the controller can estimate the brake arm velocity without any additional sensors. To suppress the brake arm velocity, current feedback control is derived and the brake noise has been reduced drastically.

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For a transverse vibration control of an elevator rope, a controller considering its nonstationary characteristics is effective in suppressing its vibrations, because the elevator rope is a kind of time-varying system. In addition, a length of elevator rope varies with time, hence, it is difficult to locate actuators and sensors for the control on arbitrary position such as center of rope and abdomen of modal vibration. As a result, we situate them at the end of rope or near the boundary based on the estimation of Hankel singular value expressing the degree to control and observe state values of controlled object. moreover, the controller having robustness for various uncertainties is valid within reducing the vibrations of object that has a flexible feature. Consequently, the main objectives of this paper are to suppress the transverse vibrations of elevator rope with nonstationary robust control methods. The suppression and robust stabilizing performances of controller are demonstrated through the numerical calculations for the case that the elevator system is subjected to shifts of tension of wire and disturbance from a building. Finally, we derive the sufficient suppression of transverse vibration of elevator rope.

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Recently, along with high-end products, users demand high quality and high added value of steel plates manufactured by the continuous steel plate process. In the factory, the continuous thin steel plate subjected to iron and steel processes is supported on a series of rollers during processes such as rolling; the thin steel plate moves on the rollers at a speed of 10m/s or more. In the plating process, the steel plate is conveyed 20-50m in the vertical direction for drying, during which the steel plates are negligibly supported by rollers and other mechanisms. Therefore, plating nonuniformity due to the generation of vibration and other factors prevents the increase of productivity. To solve this problem, we developed a new noncontact guide system for parts of the steel plate at which its traveling direction changes by applying an electromagnetic force from the direction of the edge of the thin steel plate, and experimentally examined the effectiveness of the system.

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Steel plates subjected to cold drawing, represented by steel plates for automobiles, are conveyed on rollers to undergo many processes, such as rolling, plating, coating and drying. In the handling system described above, occurrence of coating nonuniformity and flaws are a problem should be solved. Therefore, we fabricated equipment which enables the generation of elastic vibration via forced input of disturbance to a levitated thin steel plate, so that the vibration isolated effect on the elastic vibration could be examined. In this study, we aim to develop a noncontact support system of the thin steel plate as high robustness using sliding mode control, which is tolerable to factors such as disturbance with respect to variation of parameters of the system.

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