The vehicles of the superconducting magnetically levitated transport (Maglev) system travel at high speeds of over 500 km/h. These vehicles are composed of lightweight car bodies and relatively heavy bogies which are mounted with devices such as superconducting magnets (SCMs) and an onboard refrigerating system. The lightweight structure of the car bodies result in vibrations at relatively high frequencies, and are believed to be influencing the ride comfort. Furthermore, the passive electromagnetic damping is very small in the primary suspension between the SCMs installed on the bogies and the ground coils installed on the guideway. Therefore, it is effective to add active electromagnetic damping to this primary suspension. A linear generator device that is incorporated into an existing bogie of the Maglev system generates onboard power and can also generate additional electromagnetic forces that can be used in the control of the primary suspension. This device has been demonstrated in full-scale vehicle experiments to effectively apply electromagnetic damping directly to the primary suspension, and reduce vibrations of relatively higher frequencies that are otherwise difficult to reduce by controlling only the secondary suspension. Computations using a Maglev vehicle model examine the effectiveness of reducing vibrations by applying this primary suspension control.

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A methodology for analysis of a pilots' landing control at the visual approach has been developed using a neural network modeling. While our previous study analyzed flight simulator operations, this paper describes the analysis of a real flight landing case. An experimental method which utilizes image processing of recorded video data is developed to obtain necessary data such as time histories of visual cues and control inputs. The effectiveness of this proposed method is confirmed by comparing values and analysis results from the video data with results obtained using GPS/INS data. It is expected that these methods can be used to reveal the characteristic of pilot control in real flight operation.

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In order to reduce train-induced vibration, many floating tracks have been used, however, for only low-speed trains because we are not sure whether riding comfort and running safety can be maintained on floating tracks for high speed train. The authors, in this study, carried out an analysis of dynamic response and running quality of various floating tracks for high-speed train like Shinkansen. We used a simulation program, DIASTARS for the analysis. In this program, the Shinkansen vehicle is represented by a model of three dimensions consisting of a body, two trucks, and four wheelsets connected to each other with springs and dampers. The floating tracks were modeled by three-dimensional finite element method. In this study, the wheel load fluctuation and vehicle body accelerations were investigated by a dynamic interaction analysis between the vehicle and track with the train speed as parameters.

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In this paper, we aimed to model the aerodynamic force that acts on a train running at high speed in a tunnel. An analytical model of the aerodynamic force is developed from pressure data measured on car-body sides of a test train running at the maximum revenue operation speed. The simulation of an 8-car train running while being subjected to the modeled aerodynamic force gives the following results. The simulated car-body vibration corresponds to the actual vibration both qualitatively and quantitatively for the cars at the rear of the train. The separation of the airflow at the tail-end of the train increases the yawing vibration of the tail-end car while it has little effect on the car-body vibration of the adjoining car. Also, the effect of the moving velocity of the aerodynamic force on the car-body vibration is clarified that the simulation under the assumption of a stationary aerodynamic force can markedly increase the car-body vibration.

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Nowadays, various suspension control technologies have been developed such as active suspensions, semi-active suspensions and active stabilizers. As an alternative to a hydraulic actuator for suspension, electromagnetic devices have been developed. Electromagnetic devices are attracting much interest due to their high responsiveness, controllability, energy saving performance, and so on. Besides these advantages, electromagnetic devices can be connected to each other very easily. Therefore, the authors focus on this characteristic of the electromagnetic device and propose two methods to use coupled electromagnetic devices as an anti-rolling control device as well as vertical shock absorbers. The automobile experiences anti-rolling effects, such as roll damping and roll stabilization, without affecting the bouncing motion. Through basic experiments with two motors and control circuits, the performance of the proposed system is examined. The results indicate the coupled electromagnetic devices can be operated as a variable roll damper or a roll stabilizer. Numerical simulations of the turning automobile are carried out, and the results indicate the proposed system is effective.

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A series of three experiments were conducted to investigate the relation between shifts of attention in depth and subjects' visual performance or peripheral environment luminance in three-dimensional (3-D) space. Previous researchers have examined various aspects of shifts of visual attention in 3-D space. However, there were few studies to study the relationship of depth attention and peripheral environment luminance. Firstly, visual function performance of subjects was tested by means of visual measurement apparatus in experiment 1, and experimental data was divided into two groups. And then, mean reaction time (RT) of subjects was examined by changing peripheral environment luminance using a semi-realistic setting, the depth attention experiment apparatus in experiment 2. Finally, changing forecast degree examination was conducted to subjects with low visual adaptability in order to reveal the relation between delay of reaction time and forecast degree in experiment 3. The major results was shown that (1) visual performance of subjects had an individual difference; (2) shifts of attention from far space to near space was faster than the reverse under each different condition; (3) the training for visual adaptive ability can improved visual performance of subjects.

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In winter, the northern part of Japan has very deep and heavy snow, and faces the problem of freezing of the road surface. People have difficulty to walk along a sidewalk and to move from place to place in winter. This study aims to achieve efficient wintertime sidewalk administrator by applying developed ITS technologies to the snowplow. This paper describes the analysis of snow removal task on sidewalk, the mechanical type of rotary snowplow, and proposes information guidance system using Head-Up-Display, which is expected to be practically used in the near future.

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In this research, a method of designing an EPS control system that achieved a good steer feeling without using an actual vehicle was examined. Firstly, evaluation functions to evaluate steer feeling theoretically were set. And it was described that steer feelings such as “inertial feeling” and “viscous feeling” could be expressed by the evaluation functions. Secondly, a target characteristic that made the steer feeling good was determined on the evaluation function, and control methods to theoretically achieve this target characteristic were described. Finally, the designed control system was installed in an EPS vehicle. As a result, it was confirmed that the steer feeling in an actual vehicle was fine with no “inertial and viscous feeling”.

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This paper demonstrates the possibility to detect suspension failures of railway vehicles using a multiple-model approach from on-board measurement data. The railway vehicle model used includes the lateral and yaw motions of the wheelsets and bogie, and the lateral motion of the vehicle body, with sensors measuring the lateral acceleration and yaw rate of the bogie, and lateral acceleration of the body. The detection algorithm is formulated based on the Interacting Multiple-Model (IMM) algorithm. The IMM method has been applied for detecting faults in vehicle suspension systems in a simulation study. The mode probabilities and states of vehicle suspension systems are estimated based on a Kalman Filter (KF). This algorithm is evaluated in simulation examples. Simulation results indicate that the algorithm effectively detects on-board faults of railway vehicle suspension systems.

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A new design technique for panheads of pantographs used on high-speed trains was proposed to take much of the load off wind tunnel experiments on the development of the pantograph. The technique with emphasis on reduction of computational costs determines the cross-sectional panhead shape numerically, which balances low-level aeroacoustic noise property with stable lift force characteristics. An examplary panhead designed by this technique was examined by wind tunnel experiments. The test results successfully demonstrated the capabilities of the method.

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This paper describes the application of piezoelectric elements to suppress the bending vibration of a railway vehicle carbody. The elements are electrically connected to external shunt circuits. The authors carried out stationary excitation tests by using a commuter car with damper units consisting of piezoelectric elements and attachment devices. Two types of shunt circuits, an inductor and a resistor in series (L-R circuit) and a capacitor with a negative value and a resistor (negative C-R circuit), are implemented in the tests. The test results indicate that the damper units reduce the frequency response gain between excitation force and acceleration on the floor at the natural frequency up to approximately 30%.

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This research focused on reducing cogging torque in DC brushless motors for electric power steering system without causing steering feel to decline, even during vehicle operation with low steering angles at high vehicle speeds. Cogging torque magnitude was predicted by using FEM analysis, but large differences were seen between the predictions and the actual results. These differences were analyzed theoretically by using a cogging frequency formula, and the mechanism in the actual motor was inspected. As a result, it was found that if the connections among all the stator core junctions were uniform, the cogging target could be achieved.

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This paper deals with path planning for autonomous overhead cranes considering load rotation. We present conditions defining interference between rectangular loads and obstacles, and an area in which motion can be performed without interference is determined in configuration space. We then derive a secure path planning algorithm using the potential method based on a 3-dimensional diffusion equation extended to consider rotary motion. A parameter in the extended diffusion equation which suppresses rotary motion is made clear, and its effect is demonstrated. Lastly, we propose a quadratic surface interpolation method for achieving smooth path planning, and its effectiveness is demonstrated through simulation.

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The status quo of a research on a novel aerial robotic system for transportation and logistics is presented. Under a new concept for an aerial robotic transportation system, three-Dimensional Transportation Robots (3DTR) were constructed with twin turbojet engines equipped by high performance noise reduction system and a flexibly jointed delta wing controlled by 2-axis actuators. This vehicle is also stable in the air due to its pendulum structure. The first flight was successfully conducted on November 22, 2005. Flight examination of 3DTR indicates its short take-off and landing (STOL) capability.

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