"Curving" is beautiful, although "straight running" is better for high speed run. In this paper I introduce the studies related to curving performance of railway vehicles which I was concerned. At first I explain the mechanism of curving of railway vehicles and actual performance of railway bogie. Then I introduce the development of bogie rolling test stand that can simulate curving condition. In the last part of this paper I describe the results of studies related to curving, for example, research on the formation mechanism of rail corrugation on curved track, development of new bogies with high curving performance.

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This paper describes short history and present status of accessible transport. Making the railway stations and the vehicles accessible is important for improvement of mobility of disabled and elderly people. Japan has already become to the aged society whose 65+ people rate exceeded 14% in 1994. Its rate of Japan is the highest in the world, thus the transport system also most to be accessible. People should know what is needed, how make it accessible, which has the best priority, and final target must be constructed as a grand-design.

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This paper considers the historical review and the recent topics in man-machine system research for Aeronautical Engineering. Subjects include the historical development of flying quality, the requirement for flying quality, research on human response characteristics, and the relation to the control system design.

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The paper discusses the robot sensing technology in terms of improving robot functions and performances. Four topics are introduced including precise measurement and calibration of a parallel mechanism, force control algorithm exploiting a commercially available force/torque sensor, micro task with micro hand and vision system, and mobile robot & its application. These works are based on the author's own research activities.

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This paper describes a preventive maintenance technology for Jumbo-Jet. To prevent malfunction of system, there are two methods. One is to establish adequate maintenance requirement and carry out the each task. Maintenance requirement for Jumbo-jet is based on Maintenance Steering Group (MSG) logic. MSG was established in 1968 and has reviewed and updated. The other is to monitor the condition of airplane system during daily operation. The 747-400, called Hi-Tech Junbo, has Aircraft Condition Monitoring System (ACMS) and Central Maintenance Computer System (CMC).

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This study deals with a tire model for camber thrust and camber torque on a damaged road. At first, the tire characteristics with camber angle are measured. And, the design parameter of brush model, for example contact surface, width characteristics, change to radius of tire and so on, are also measured. In this tire model, we defined that the contact surface is related to the tire camber angle and load, the radius and contact pressure are changed according to the area. Finally, it is shown that the calculation result of the tire model has a good expression for camber thrust and camber torque characteristics.

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It is known that there are some problems about the mechanical system with both collision and rolling contact. But they haven't been discussed widely to solve more general cases with elasticity such as rubber tires of vehicles. So this study is focused on dynamic behavior of rolling elastic body in collision and understanding its mechanism. Then, the formulation is proposed for the state of contact of rolling ball in collision with considering the effect of sliding, friction and elasticity, in order to accomplish the numerical simulations for such a system. As the result, it is shown that there are some differences in the displacement and rolling speed after collision between the methods with elasticity and without it.

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This paper is concerned with the running stability of tractor-semitrailer systems at braking. Firstly, we construct nonlinear equations of motion for the articulated vehicles which have 9 degrees of freedom, i,e., forward, lateral, yawing, rolling, pitching, and relative yawing motion. Secondly, Simulation study is carried out to show the vehicle performance in realistic situation. By using the concept of load rate of each tire, we confirmed that the model shows the motion of limit performance conditions at the braking. Finally, the relationship between limit performance, road gradient condition, and vehicle parameters is shown.

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Usually, driver is notconsidered in the plant of control systems. Therefore it's not sure if those systems are stable under the driver control. In order to make heavy-duty vehicle stable under driver control, the plant are defined as a vehicle only and a vehicle with driver, and then controlled by LQG or H_∞ controller. Comparing these results, it is confirmed that H_∞ control system is useful to improve stability of Heavy-Duty Vehicles and quite effective on the robustness for design parameters changes.

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This paper studies on the equations of motion for aircrafts flying in steady and unsteady wind, and represents the process for obtaining them based on the definition of inertial system. The main results are as follows. (1) There are two kinds of system moving relatively to a basic inertial system. The one moves along with observer, the other one moves along with atmosphere. (2) The basic inertial system in atmospheric and gravitational field is the atmosphere-fixed system, which is at rest or is moving at constant speed to the ground, (3) The principle of relativity in atmospheric and gravitational field requires to add the following additional condition into Galilei's principle of relativity; "the atmosphere is also moving along with the moving system at constant space"

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This paper describes a Optimum Shipment Management System for Warehouse. These days, it's important to minimize the shipment lead time instead of the storage function for warehouse. The problem is the arrangement of shipment orders from the customers. Simulated Annealing (SA) method is used for this problem. SA method is effective to find a optimum arrangement of shipment orders automatically in short time. And in the case study, SA method has found a optimum arrangement which generates minimized shipment lead time compared with the common shipment method by the total picking system or the order picking system.

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PID control schemes still continue to be widely used for most industrial control systems. This is mainly because PID controllers have simple control structures, and are simple to maintain and tune. However, it is difficult to find a set of suitable control parameters in the case of time-varying and/or nonlinear systems. In this paper, a new gain scheduled PD controller design scheme and self-tuning PD controller design scheme are proposed. The PD parameters are calculated on-line based on the relationship between the PD control law and pole-assignment control law. The proposed schemes are numerically evaluated on sway control system of a lifted load for a mobile crane. Numerical results illustrate the effectiveness of these new schemes.

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Operating a traveling crane in the plant is very hard, so that an automatic control of the crane operation have been expected. This study describes automatic traveling motion control of the crane system for the purpose of suppress swing a load at several cases. Automatic traveling motion control requires that both the swinging of load and position tracking of the cart are controlled simultaneously. H^∞ servo controller based time domain characteristics is adopted in the controller design to improve robust performance. Some experiments conducted in various condition of loads. Experimental results shows effectiveness of the H^∞ servo controller. A reason for achieving robustness to modeling error at the band of high frequency was confirmed by controller design which suppressing frequency characteristic of the complementary sensitivity function.

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In Japan, many efforts have been concentrated to protect the infrastructures and fundamental facilities for cargo handling in harbor from seismic hazard. As one of these efforts, the container crane(c/c) utilizing the base isolation device was successfully produced and applied for the seismic resisting berth in Ohi wharf in Tokyo. Authors developed the base isolation device consisting sliding mechanism, restoring mechanism, energy dissipating mechanism and trigger mechanism and installed 4 units between each bottom of leg and gantry traveling portion of the container crane. During the earthquake, main structure shows the sliding motion by the work of device, so that the natural period of the structure becomes longer enough to avoid the seismic force in the dominant frequency band. In the full paper, detail of the experimental investigation for the performance of the isolation about the scaled-down model and result of the computational simulation will be introduced. Result of the excitation test about the practical c/c will be also included.

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Non-contact power transmission system can be applied to power stacker crane of AS/RS (Automated Storage and Retrieval System). Non-contact power transmission gives some advantages such as non-spark by chatter and/or non-dust by friction. The power system contains: (1) power supply to generate primary current, (2) primary line to distribute electromagnetic field along the crane runway, (3) pick up coil to gather power from the primary line through electromagnetic coupling. In conventional applications, the power supply is required to set the primary current continuously during the system on duty or standby. And the primary current is generating loss in primary line at any time even when the crane consumes low power (e.g.: when the crane stops waiting next command). By reducing the primary current corresponding to the crane power consumption, the primary loss can be saved.

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Traffic safety is the most important subject in present automobile transportation. Traffic congestion also makes both economical and ecological loss. In order to solve these problems and to achieve more efficient traffic, research and development of ITS have been getting more important. The authors developed a test vehicle for this object. One of the features of the test car is to measure the both of behavior of car itself and it's surrounding condition such as the behavior of the other cars in traffic. This paper presents brief introduction of the developed test vehicle for ITS research.

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This paper proposes the new control concept of driver assist function using the information of vehicle's frontal road and traffic environment such as a road shape, and a road and obstacle positions relative to subject vehicle. In ITS technology, full autonomous vehicle control is the 21century's human dream, but there will be very high technical walls to overcome. On the other hand, practical semi-autonomous systems such as Adaptive Cruise Control System which has already on market or can be realized soon have low potential to improve safety. So, we designed intelligent control assist system, in which the liability for safety fully dues to drivers. Computer simulation proved that the proposed intelligent drive assist system has the possibility of improving driver's control performance greatly in the view point of active safety.

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Japan is the second largest petroleum consumption country in the world. Therefore, CO_2 curtailment to prevent the greenhouse effort is imposed on Japan as an international pledge. However, the amount of CO_2 exhaust from automobiles are still increasing in Japan. Therefore, a drastic innovation of traffic policy and technology is needed. Then, the effect of jumbo trains that substantially cut the CO_2 emission from automobiles is discussed when they are integrated with the road traffic ITS.

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This paper considers automatic emergency recovery control system of an accident aircraft. This system is divided into three parts, 1) Neural Network identifies deterioration of control inputs and bias forces due to accident or failure, 2) the distribution matrix which distributes required control forces to control inputs are adjusted by using the identified control effectiveness, and 3) the numerical optimizer modifies the reference inputs of flight controller. Numerical Example demonstrates the control process of an aircraft with unexpected actuator failure and indicates the importance of artificial control inputs for learning the Neural Network.

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This research described construction of a traffic simulator as the evaluation tool that contained each vehicle characteristic, driver characteristic, environment information and so on. In this study, a basic design for the traffic simulator is shown as the 1st step of the research. A risk model is used as driver model. The validity of risk model is verified by experiment of 45-degree turn. Finally, the interaction among vehicles is examined by braking simulation.

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Recently, automatically controlled vehicles are expected as the solution of the problems which the automobile society holds, and various researches are advanced. Platoon has been studied as one form of the automated driving. As for the longitudinal control in the platoon, the stability in the platoon is important, when the high-density platoon is considered. The purpose of this research is to design the controller to improve the stability of the platoon. This paper proposes the controller that treats a spacing control as a vibration system and discusses the effct of sky-hook damper in vibration system. Simurations are conducted in the case of using only preceding vehicle information and using both preceding and following vehicle information.

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This paper proposes a vehicle path tracking control system for vehicle equipped with four-wheel steering (4WS) system. Although conventional front-wheel steering vehicle can be employed for path tracking, it is impossible to achieve desirable control performance in both lateral and yaw motion from the viewpoint of vehicle dynamics and control. On the other hand, steering the rear wheels permits the vehicle path and attitude to be controlled independently of each other. Based on this merit, 4WS path tracking control system is designed via coordinate transformation to decouple lateral motion and yaw motion during path tracking maneuver. Finally, its validation and effectiveness are investigated by computer simulation.

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Several methods are proposed for investigating the complex traffic flow. However, the dynamics of vehicle and the driver's characteristic, which are important factor for the traffic flow analysis, are not considered enough so far. This paper describes a new concept for simulating complex traffic flow by multiagents. The agents are considered as a kind of artificial life (A-Life) and they behave based on their own knowledge independently. Drivers, vehicles, roads and traffic environment, which are essential elements in our simulation, are defined as the agents. The vehicle agent combined with a driver agent works based on driver's region of sight and their own characteristics. The road agent communicates with the vehicle agent responding velocity, position of the vehicle. The effectiveness of our new method for modeling the traffic flow is shown by simulation study.

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Effect of real-time traffic information on the relaxation process is studied. The provision of traffic information on a real-time basis to individual vehicles is expected as an effective way to distribute the traffic flow to a network of roads. However, it has been also pointed out that real-time information prevents the distribution of the traffic flow on a network of roads because of the concentration of the traffic flow to the recommended route. We can see that the real-time traffic information based on averaged velocity or travel time give rise to fluctuation with chaotic structure on the relaxation process of traffic flow formed by cellular automata. It is also proposed that the real-time traffic information composed by differentiation of averaged velocity of vehicle is effective to reduce the fluctuation of traffic flow.

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The practical active exhaust muffler using ANC system was studied for reducing the harmonics of basic frequency which are the main components of exhaust noise generated by a medium-duty diesel engine truck during the period of acceleration. The muffler structure which reduces the thermal affect to ANC speaker by exhaust gas, was designed, and the time base Synchronized Filtered-X method with a modified variable stepsize algorithm was proposed as the control strategy in time-varying environment. The effectiveness are verified after applying the ANC system to the exhaust noise control of the truck on the condition of accelerated running.

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A various kind of studies regarding ship noise are being carried out today. Nippon Kaiji Kyokai started studies more than fifteen years ago, and published the results in the form of guidance. Moreover, to deal with rationalization of ship noise, the authors have developed a computer program (hereinafter "KNOISE") to estimation noise levels in the accommodation spaces and engine room of a ship. KNOISE has an excellent user interface offering ease of operation, reduced data input through the use of standard tables, and an interactive data input system. Accordingly, in order to examine the validly of KNOISE, the authors have carried out to make a comparison between measuring data and results of calculation. This paper briefly outlines KNOISE and its development until now. The efficacy of "KNOISE" is inspected through a detail analysis of the measured data and numerical investigations.

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The purpose of this study is to predict the room interior noise level generated by running of the elevator. Firstly, We leaded the structure borne sound analysis by Statistical Energy Analysis (SEA method). For using this method, we measured the mechanical parameters of the building materials. Finally, We confirmed the good agreement between the calculation and the measurement of the noise level of the practical apartment building.

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Elevator lateral vibration is the main problem for ride comfort in high-speed elevators. Such vibration is mainly caused by guide rail deformation and guide rail arrangement errors. In order to improve ride comfort, it is important to achieve an optimum design and estimation of the cage suspension system by considering these guide rail irregularities. So, we have developed a new simulator for elevator lateral vibration. In this paper, (1)we make the difference of roller guide behavior clear between as elevator cabin is stopping and as running. (2)we make the simulation model including such a transient behavior of roller guide. (3)we verify that the simulator is extremely precise by comparing the simulation results with experimental results of cabin floor acceleration.

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This paper describes malfunction of vehicle suspension by wavelet transform. Using two degree of freedom vertical vibration model of the rolling stock, the signal with the signal in which the amplitude changed was created. By the Wavelet transformation, it was tried that the weak and abnormal signal which is buried under the noise was detected. Acceleration signal including malfunction is generated by 2D of vehicle model. It is pointed out that the detection of malfunction under measurement noise can be possible by wavelet transform.

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This paper deals with improving the riding quality of heavy-duty tractor-trailer. It is constructed that a half truck model of 9 degrees freedom. The influence is discussed which of the parameters of cab suspension on the riding quality of truck. It is done that the simulation of step response and random response with cab semi-active suspension damping control. It shows that the riding quality of truck is improved with the adjustment of cab stiffness and cab semi-active suspension damping control.

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In this study, the optimum design method which were efficiently able to design the complicated three-dimensional flame structure by using Genetic Algorithms was described. This method having the pre-post processor and it would be able to observe the input/output results and the situation of the resolution during the analysis. The method applied to the box-type three dimensional flame strucrure, and the appropriate results was obtained.

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This paper describes a prediction method for ride comfort during running of a railway vehicle. At first, vertical acceleration levels on the floor of a car-body were calculated by using FEM. In this case, measured vibration levels of the axle box were used to excite the car-body structure. Next, the vibration response of the head, shoulder, waist, and foot for the seated passengers were predicted by using the database of the transfer function. And, the ride comfort considering the human sensitivity was estimated from these vibration levels. The predicted results of the ride comfort were compared with the measured, and it was confirmed that the method was useful. As an example, the analysis by changing the specifications of a car-body was carried out by using this method to improve the ride comfort.

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When we evaluate the human-machine-environment systems, it is very important to consider not only the performance of the machine system but also the Mental Work Load (MWL) for the operator. Because human being have a high adaptability to their surroundings, Therefore, we constructed the dynamic model of the human-machine-environment system using the Heart Rate Variability (HRV) in the past. However, It is difficult to construct the dynamic model and also even to analyze it. Therefore, in this research, we deal with possibility of the static model for cause of the MWL using RRI. To use this model, we analyzed the influence of the RRI about driver's information processing using the factor analysis. Finally, it is found that the model has a possibility to show the difference of the driver's information processing according to course.

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To evaluate further the car concept "Silver Vehicle" which we've reported at the previous session, we performed "Town-Mobility Exepriment" in Takanosu town, Akita pref. In "Town-Mobility Exepriment", a number of electric scooter and super small EV was freely used in the center of Takanous by more than 60 older people. As a result of it, we learned that super small EV was very available for older people and had a great possibility for practical use. We conclude that offering the way of maintaining elderly people'mobility (for example, to oleder driver who may abandon to drive a car possessing SV brings improvement of their mobility) could raise their QOL efficiently.

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The amount of truck drivers who are suffering the chronic lumbago is not small. Driver often makes improvement to lessen the driving fatigue by adjusting the seating attitude where his back torso angle is increased and the stress to the intervertebral disk is reduced. This effectiveness is testified by the data of eletromyogram at elector muscle of spine and catecholamine from urine.

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A sitting comfort of three automotive seats (a middle class car, a low class car, and a light car), whose cushion angles were changed 0°, 8° or 15° and back angles, surface materials and pad shape were the same, was evaluated by only human tactile sensation while sitting on these seats. As the result of the sensory evaluation, three grade seats whose cushion angles were 8° were evaluated the most "high-class" and those seats whose angles were 15° were evaluated the most "sporty". Further a pressure and a contact area distributions between the human body and the seat were measured by a tactile sensor system while sitting on seats whose cushion angles were 0, 8 or 15°.From the result of correlation analysis among the cushion angle, the pressure distribution and the sensory values of sitting comfort, it is found that the "sporty" and "hold" feeling increases as the cushion angle of the middle class car increases. The "support under the femoral region" feeling increases as the angle of the low class car increases. And the "hold" feeling increases and the "comfortable" feeling decreases as the angle of the light car increases.

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The purpose of this paper is to determine how and where pilots watch the observation cues during aircraft landing such as runway, horizon. Furthermore this paper investigates the relative importance of each visual cue available to pilots, the relationship between visual cues and estimation of state variables and how the pilot gain change in order to minimize the state estimation error when some visual cues are lost. It's found that visual cue of the both side edges of the runway are more important than the others in the state estimation in the final approach phase. Furthermore the pilot gain decreases when the important visual cue is lost and increases when the altitude becomes lower.

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