It is known in the horizontal header with a vertical branch pipe, the biased distribution of liquid phase will be happen when the vapor phase enters into the header. The authors have shown that it is possible to suppress the liquid biases by using the proposed header with the protrusion branch pipe, which can keep a uniform of liquid distribution when little vapor is mixed into. When the accident occurs, a large amount of vapor is mixed into the header, we focused on the liquid distribution flow and target a mechanism that can suppress the bias of liquid phase in the research. In this research, distribution of liquid from header with increasing gas phase is researched to check out whether the uniform liquid phase distribution can be attained. We tried to make new type header to avoid the effect of shear stress from air flow to water flow by changing the shape of header, and checked its effect. We found another effect for un-uniform distribution by changing the shape, but we also found suggestion to get the uniform distribution.

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Parametric study on steam condensation in a heat transfer pipe in various condition has been executed considering evaluation of condensation behavior in Isolation Condenser (IC) equipped in BWR-3 which was operated in Fukushima Dai-ichi NPS as unit #1. Horizontally placed U-shaped heat pipe was installed in a large tank, and saturated steam was injected into the U-shaped heat pipe changing its flow rate. Temperature, pressure and flow rate in the experimental loop were measured. Especially for inside temperature of the heat pipe, 13 thermocouples were installed into the heat pipe from upward and downward individually with consideration of temperature change from saturated condition due to cooled water which originally appeared by condensation inside the heat pipe. Steam was supplied by electrical boiler of 50 kW, and installation of bypass line before the test section successfully avoided the effect of intermittent ON/OFF control of the electrical boiler. The apparatus was shaken down and confirmed about the accuracy of installed sensors or controllable range of the condensation condition inside the heat pipe, and at last widely varied conditions of condensation inside the heat pipe were observed and the availability of the apparatus was validated.

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Heat transfer enhancement method using fins is well known and widely used. It is superior to smooth tube in heat removal. However, it needs to consider the loss of structural strength on the heat transfer surface by attaching fins. Therefore, we proposed a heat transfer enhancement method using porous materials, especially in case of inserting with interval. It can save process to consider the loss of structural strength and can set easily. Air is blown inside the circular tube which is heated using heater. Outside wall of the tube is insulated. Heat removal and pressure drop is measured for evaluating the method using porous materials. Reynolds number is set to 700, 1200, 3000, 5000 and 8000. Heat flux is constant during experiments. Copper wire (Diameter: 5mm) is used as porous materials. The wire is cut off in three blocks with air gap and inserted with interval in the tube. When porosity changes from ε=0.997 to ε=0.998, heat removal falls big. The experimental results indicated that ε=0.996 or ε=0.997 is optimum.

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Higher thermal efficiency and operational flexibility are required for next generation thermal plants to reduce CO_2 emission and cope with the increase of power by renewable energy which is changeable depending on the weather. The Advanced Humid Air Gas Turbine (AHAT) system is expected to meet these requirements. The system concept and cycle performance of the AHAT system were verified by operation tests of a 3MW-class test plant and a 40MW-class pilot plant so far. However, the operational flexibility of the system has not been clarified sufficiently by experiment or calculation. Therefore, we develop the dynamics simulation model of the system and analyze the load response characteristics in this paper.

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This report is concerned with dynamics of steam supply in an energy system that consists of distributed plants producing, consuming, and interchanging steam. This type of steam supply system has been recently addressed and become significant in the context of energy systems integration. In order to consider a novel operation of multiple boilers including cogeneration or heat pump plant, a lumped-parameter model has been derived based on the incompressible gas-flow equations. This report numerically verifies the derived model by comparing with combined simulation of the homogeneous two-phase flow equation and the standard boiler model. The influence of heat loss and pressure drop on dynamics of steam transport is investigated by using COMSOL Multiphysics simulator.

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Ground source heat has recently attracted considerable attention as renewable energy. The temperature of the underground at less than 150m depth is constant by geothermal energy throughout a year. Thus, a ground source heat pump (GSHP) system is an efficient means of saving energy. The GSHP releases heat at a cooling mode to the underground and extracts heat at a heating mode from the underground. This paper describes characteristics of extracting and releasing heat from / to the underground by exchanging heat of GSHP using direct expansion method. As a result of the experiment, the releasing heat increased the underground temperature of 15.9℃ in the cooling mode. The extracting heat decreased the underground temperature of 13.2℃ in the heating mode. The average of COP approached to about 11.8 in the cooling mode and 5.5 in the heating mode. Then, the releasing heat is 110 W/m and extracting heat is 93 W/m in secondary side. It was found that the influence of cooling mode is larger than heating mode, and it might not exchange the heat well in the heating mode.

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The ground source heat pump is one of the energy-saving equipment. The performance of the ground source heat pump (GSHP) system is better than the general air heat pump system. The ground source heat pump using direct expansion method has higher performance than the ground source heat pump using indirect heat exchange method. It is also expected to be practical since it can reduce initial costs. The geothermal heat exchangers consist of the heat collecting pipes that exchanges heat from the ground. The direct GSHP system had experimentally demonstrated in cooling mode. The result indicates that the performance is influenced by outside air temperature but the value of COP keeps around 10 which is much larger than that of air heat pump systems.

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Geothermal heat pump (GSHP) system is expected as the method of energy saving but it is not widely used in Japan. It is because its initial cost is more expensive than the heat pump system using air. This paper describes the experimental result obtained by using the water cooling of GSHP whose initial cost is lower than regular GSHP system. This system use existing two wells. One is 30 meter in depth and it is used as bore hole. That is expected to save the digging cost of bore hole. The other is 50meter in depth and it is used as system recovers temperature of underground. The proposed system is evaluated by Coefficient of performance (COP). COP is used commonly as index indicates the performance of GSHP. These results show that COP of this system is 3.5 during cooling operation and 2.2〜3.0 during heat operation. It is necessary to keep pouring groundwater during the operation of the Water Cooling Indirect Methods of GSHP.

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In this paper, we discuss relation between amount of absorbing material and noise suppression effect. We perform restraint of a noise radiated effect by enclosure opening to investigate the most suitable amount of absorbing material. In addition, we change the position of the opening at the enclosure. There are two steps in the method. First, the sound pressure and acoustic particle velocity in the enclosure are calculated by FDTD numerical simulation. Next, we examine the arrangement of the acoustic absorbing materials to decrease the acoustic power of the emitted sound from the opening based on the numerical results. As a result of numerical analysis, it is possible to effectively suppress noise by arrangement of the absorptive material based on the distribution of the magnitudes of the particle velocities.

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In this paper, we present acoustic characteristics of noise barrier for machine noise. We propose the noise reduction using noise barrier having two apertures. We also propose appending a duct to one of the apertures in the noise barrier. And we examine acoustic directivity without/with duct in the noise barrier. Finite difference time domain numerical simulation is performed to calculate the sound pressure and the particle velocity in the near field. The acoustic directivity can be estimated from that particle velocities at measuring surface which is located in the vicinity of the noise barrier. The sound pressure in the far field is proportional to the size of aperture. Noise reduction levels are proportional to the duct length. It is necessary to consider positions of apertures in the noise barrier to improve performance of noise suppression.

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Drum-like silencer has the structure where the membrane and the sound absorptive material are combined. The structure is placed in parallel to the propagation of sound wave in the duct sound field. The purpose of this study is to clarify the acoustic noise suppression mechanism of the combining a sound absorptive material and an elastic plate. We investigate vibration effect of elastic plate against the transmission loss experiment when sound wave enters parallel to the elastic plate is placed in a side of the duct. The double pair microphone method is used in the experiment. Large transmission loss can be achieved at the natural frequency of each plate.

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In this paper, we describe acoustic characteristics of noise control device with absorptive material and an elastic plate. The devices with absorptive material and elastic plate are used in sound absorbing louver and various silencers to improve the performance of noise control. Configuration of simulation model consists of a rigid-walled square duct and the noise control device. Numerical analysis is carried out by finite difference time domain (FDTD) method for sound field and plate vibration. In order to verify the numerical results we examine the transmission losses of the sound absorbing devices and frequency responses from applied force to sound pressure at microphones in the duct. The calculated results and the experimental results of the transmission losses and the frequency responses show the same tendency.

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Soundproof walls are installed on railway concrete viaducts to reduce the noise from running trains. Recently, the soundproof plates made of transparent polycarbonate have been additionally installed on the present soundproof walls on concrete viaducts. However, the higher the soundproof plate is, the larger is the wind load which acts on the viaduct. Then it is almost impossible to install high soundproof plates without reinforcing the viaduct sufficiently. Therefore, we have developed new soundproof equipment which is composed of polycarbonate of 8mm in thickness for noise insulation and metal frames. The soundproof plate of this equipment is supported by rotating shafts on the both sides and fixed by magnetic force at its bottom. The plate opens in case where the wind load exceeds the threshold value of the design of the viaduct, which results in reducing the load transmitting to the viaduct to less than its design wind load. Heretofore, it was verified in a tunnel test that the plate opened as expected in the case of strong wind and reduced the wind load acting on itself. Train operators demand that the plate should close immediately after the wind weakens below a certain level. In this paper, a new closer was introduced to obtain non-linear torque to close the plate. Wind tunnel test and exposure test in a heavy storm ware carried out to confirm the effectiveness of the closer.

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A removal efficiency of turbidity is sometimes reduced in an sedimentation basin equipped with inclined plate settler in summer afternoon by the cause of density flow. The purpose of this study is to clarify the flow structure of density flow and improve the removal efficiency. The three dimensional numerical simulation was carried out to clarify the details of flow structure in a sedimentation basin, by considering the change of inflow water temperature. The results show that the density flow occurs when the temperature of inflow water raised, and forms the non-uniform flow field by an increment of upward flow velocity in the settler. This phenomena causes the carry turbidity matters over from an overflow trough, and worse the treated water quality. Furthermore, effect of baffle plate was examined to reduce the influence of density flow and confirmed the improvement on the water quality.

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While depletion of metal resources are concerned, in the industry to recover the valuable metals from industrial wastewater, reuse technology has been attracting attention. In this study, flotation method is based as a way of removing valuable metals, surfactants and fine bubbles (Micro-Bubbles: MB, Nano-Bubbles: NB) were applied flotation method using. In the conventional method, it has to recover the metal fine particles is primarily added to the high concentration of surfactants, which affect the water quality environment in question. Therefore, by applying the fine bubbles, it is expected to reduce the surfactant concentration. Currently, when applying the MB to flotation process, although the reduction amount of the surfactant has been reported affects reported recoveries type and the amount of the surfactant is small. From this point of view, assuming the factory waste and waste liquid discharged in the recycling of such electronic industry, we attempted to flotation and recovery experiment of the valuable metal particles by blowing of the fine bubbles. This time, to select the difference from Fe_2O_3, In_2O_3 of potential, was reviewing the impact, such as the surfactant concentration on the recovery rate. As a result, in the recovery experiment of Fe_2O_3, if it reduced the conventional surfactant concentration to 1/10, it was confirmed that to allow about 90 % of the separation and recovery. Furthermore, even in the recovery experiment In_2O_3, similar results were obtained. Thus, it is possible to recover the various valuable metal particles without affecting the environment is revealed.

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Currently, the resin material is used a lot as a printed circuit board. But, resin material has problem such as landfill or hazardous gas generation. From the viewpoint of environmental protection, a biodegradable resin that is decomposed into water and carbon dioxide by microorganisms has been expected as a substitute material for the conventional resin material. However, since degradation behavior of the biodegradable resin is not clear, a decomposition and recovery technology method has not been established. In this study, The main material used polylactic acid, it scrutinize the degradation properties of the substrate material which is multi function by adjusting the microstructure. As a result, decomposition characteristics of substrate material of function improved has not lost. Also, a significant difference was confirmed in the degree of progression of decomposition by changing the environmental solution. Therefore, it was suggested that the selection of the microstructure adjusting or environmental solutions was able to accelerate or control the degradation.

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Yearly 13 million tons of coal ash (clinker and fly ash) are domestically generated as the industrial waste. Fly ash is commonly used as a part of roadbed materials whereas clinker ash is limited in use. In this study it is focused on available uses of clinker ash because it has the outstanding characteristics of water retention and absorption. We tried to sinter clinker ash mixed with auxiliary agents; white earth and glass, and to produce the porous material. Soda-lime glass beads were especially used, instead of waste glass disposed throughout the domestic area. Several kinds of properties obtained in the experiment were compared with the standardized values and with the results obtained by commercial block to evaluate as water retention block. Finally it was found that porous materials of clinker ash with both white earth and glass were enough suitable for the production of water retention block.

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We examined the pulverizing characteristics of woody biomass by three defferent sizes of dry mills with ring-type pulverizing media. This type of mills have many pulverizing rings in the inside of the pulverizing cylindrical chambers and these rings roll and rotate in me chambers by external vibration. Woody biomass are pulverized by this high rotational centrifugal force. Two kinds of woody biomass: cedar and douglas fir were used for pulverizing tests of these mills. Pulverizing energy consumption of each of mills was inversely proportional to the amount of input materials. When the amount was too large, the pulverizing was no longer proceeding. The study of the pulverizing characteristics of small and large dry mills leaded to the definite relationship between the pulverizing energy consumption and saccharification efficiency of woody biomass. The relationship was independent of the physical size of mills. Input power per area of pulverizing chamber is about 15 kw/m^2. Then, it was estimated that woody powder was heated by large pressure from pulverizing rings and the average temperature of this woody powder layer achieved at about 300 centigrade.

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In order to make effective use of biogas generated in a sewage treatment plant in cold and snowy districts, more efficient storage can be expected with gas hydrate formation. In this study CO_2-hydrate formation in crushed ice layer was tried with an enclosed pressure vessel, assuming the combination of snow ice and biogas. On the other hand, much difference of the hydrate formation time on every experiment was obtained and various conditions of ice melting would be predicted as the cause. To clarify the effect the experiment was achieved with cooling vessels for hydrate formation and with addition of cooled grass beads. As one of the results their cooling methods gave stability on the formation and shortage of the duration. Higher formation speed was also expected if the ratio of melting enthalpy, defined as the formation possibility, reached around 30%.

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This paper deals with the characteristics of the two-phase flow distribution with using the R134a as refrigerant. The experiments are performed by using a test section of the header type distributor as a model of an existing heat exchanger. This test section moves downward vertically with three branches and uses the pump as the circulation of the refrigerant. The branch tubes are micro-channel multi-port tube made of aluminum and the header tube is made of transparent acrylic resin, so that the flow distribution of two-phase flow can be clearly observed. To investigate the effect of the flow rate, the pressure condition, the inlet vapor quality on the two-phase flow distributor, the experiments are conducted under a variety of experimental conditions. Finally the relationship between these experimental parameters is discussed.

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It has to be applied to control the linear control theory to the system that was linearized by a linear approximation in controlling because most of the system to be real has nonlinearity. But control effect is not obtained in this way. This paper applied the gain schedule control to the non-linear parameters, and verify the usefulness. The simulation results show that gain scheduled control obtained good control effect than H-infinity control.

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Hardware In the Loop Simulation (HILS) system for seawater desalination plant was developed. This HILS system mounted simulation model of the plant on a digital signal processor (DSP). As real plant can be replaced by the DSP, we can adjust control equipment for the plant by using the DSP before the plant completion. In modeling of constituent equipment, characteristic curve was linearized locally for reducing analysis time, and analysis accuracy was improved by reducing time inclement. Simulated result from the developed HILS system was in good agreement with measured values of real plant.

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This paper presents a compensation approach for the nonlinearity in rotary-direct drive servovalves. The target servovalves have an unique mechanism, where a rotary motor directly drives the spool through the rotation-linear motion converting mechanism. However, the nonlinearity such as backlash in the mechanism deteriorates control performance. In this paper, therefore, disturbance observer is designed to compensate for the deterioration factor in the valve. Effectiveness of the designed controller has been verified by experiments.

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Guaranteed cost control is a method for the robust control problem of the LTI-systems with structured uncertainty. In such systems, the performance index is perturbed by the effect of uncertainty. So this method design the robust stable system to guarantee the existence of upper bound of performance index. On the other hand, the networked control system is investigated. The LTI system plant and controller are connected with communication bus. The input and output signals are transmitted by previously defined periodic pattern. The whole system characteristics is constructed as periodic system. This issue consider that the application of guaranteed cost control to the networked control system with the plant includes the uncertainty in an input matrix.

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Spark test is a test for examining compositions of steel such as the amount of containing carbon and that different materials are not mixed. The spark test is made by a skilled person who grinds an end surface of the steel using a hand grinder to determine the contained material by watching the shape and density of the spark. Some researchers and engineers try to develop automatic spark test machine. Because of importance of generating stable spark, a spark generating machine has been developed. However conventional PID control with force feedback tends to cause the vibration or hunching. Therefore we discuss an application of the impedance control for force feedback. In this paper, firstly, we develop a simulation model of the spark generating machine in a computer. Then we verify if the PID control in the simulation model causes the vibration or hunching phenomenon. Next, the impedance control is applied to the simulation model. We found the critical values of the impedance parameter to suppress the vibration or hunching phenomenon

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We consider a point-to-point motion of a flexible arm mounted on flexible base, and then propose a trajectory planning method for reducing the residual vibrations and driving energy simultaneously. In the proposed method, the joint angle of the flexible arm is expressed by a combination of polynomial and cycloidal functions. In this case, the trajectory profile of the joint angle is dependent upon the coefficients in the polynomial function. In order to minimize the vibrations of the flexible arm and base after the positioning and the driving energy of the joint angle simultaneously, the coefficients are tuned by a multi-objective genetic algorithm, and then the optimal trajectory can be obtained. By rotating the joint angle along the obtained optimal trajectory, the residual vibration can be suppressed with a minimum energy, namely, the proposed trajectory planning method is classified into feedforward vibration control techniques. The validity and effectiveness of the proposed vibration control scheme are substantiated by simulation results. Moreover, we investigate the effect of the flexibility of the base on the driving energy.

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The study provides the simple method of automatic lateral guidance control. In most of previous studies, control law about automatic guidance control is complex. We were able to simplify guidance control, converting non-holonomic system into holonomic system about lateral movement. The side-force-plate unmanned aerial vehicle (UAV) has capable of turning at low bank angle. The side-force-plate is a wing that is attached nearby the center of gravity. Utilizing characteristic of the side-force-plate, it is able to convert non-holonomic system into holonomic system. Specifically, we enabled UAV to lateral movement using rudder only, stabilizing roll movement by a controller stabilizing attitude. A LQG controller utilized for the sake of stabilizing attitude of UAV. It is able to guidance control utilizing a proportioning controller. In other words, we executed lateral guidance control, feedbacking guidance angular velocity multiplied gain to rudder angle. We verified efficacy of the guidance controller via a flight test.

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In this paper, we study turning control of UAV with fixed side force plate that uses visual feedback as a method to turn around an acquired target. The UAV turns using the centripetal force generated by the fixed side force plate as the aircraft side slips by rudder steering. As a result, we can reduce bank angle of UAV. However the control of image processing didn't function to well. After this we will correct the method of visual feedback.

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This study develops a rotary active vibration control device (AWD) using a flywheel to control vibrations in flexible structures. The AWD achieves lightweight and higher inertia by the flywheel and can be mounted on the flexible structure easily. In addition, the AWD can construct sky-hook control easily because it can measure the absolute angular velocity of the flexible structure by the gyro sensor. Therefore, The AWD use Sky-hook With Adaptive Disturbance Cancellation (SWADC) control which is combined control system of sky-hook control and adaptive disturbance cancellation control. This paper investigates a method for cost-performance improvement of the AWD by using the dynamic quantizer for practical use. In general, performance deteriorates according to using low cost instruments. So this study uses the dynamic quantizer to prevent performance deteriorates of the AWD. In addition, the parameters of the dynamic quantizer is optimized by Genetic Algorithm (GA). Cost-performance improvement of the AWD is shown by simulation.

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This study investigates method for an achieving scalability and long hour continuous operation for a vibration-isolation table supported with a redundant number of pneumatic actuators. In this study, a vibration-isolation table is supported by more than three actuators over the three degrees of freedom (DOF) of table's motion to decrease load per one actuator. This study develops the technique to exchange a control system stably when increasing and decreasing of the number of the actuators in response to the case when changing supporting weight, changing position of a center of gravity of the support load due to the change of the device of a vibration-isolation object, and the case when actuators break down. Therefore, this study constructs procedure for decreasing the number of actuators. Proposed procedure is a fundamental technique necessary to construct a scalable vibration-isolation table in which the actuators supporting the table can be added or removed flexibly.

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A flux-path magnetic suspension system was fabricated in which the three-degree-of-freedom motions of the floator was actively controlled. In this system, a control plate with four rectangular permanent magnets for magnetic concentration were used instead of ferromagnetic control plates in the conventional flux-path magnetic suspension system to increase the suspension force. The three-degree-of-freedom motions of the control plate were controlled with four differential electromagnetic actuators according to the motions of the floator. Contactless suspension was achieved by applying PD control in the fabricated suspension system.

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Although there have been considerable number of technical papers that deal with free vibration of flat plates made of metal and composite materials, the vibration behavior of thin and thick sheet glass plates has not been clarified enough, and there has not been reported to answer the question of whether the classical plate theory is applicable to sheet glass plates. In the present report, vibration analysis and modal analysis measurement are conducted to compare both sets of natural frequencies and mode shapes, and the applicability of the conventional vibration analysis method is confirmed.

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This article is concerned with the identification of chaotic behavior from a time serious which is obtained by numerical simulation or experiment. The method of identifying chaos based on the results of continuous wavelet transform of the time history is proposed. With the results of the wavelet transform, the energy distribution is obtained. For a chaotic time history, the distribution will also show the chaotic behavior. With this idea, the chaos index is defined to describe this random like behavior numerically. Then observing the chaos index may allow us to identify the chaotic time history quantitatively. Numerical experiments are provided to demonstrate the proposed method.

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The comparison method between input powers and contribution rates from power sources to a simple structure consisting of two flat plates and a partial car model consisting of four subsystems in machine operation determined by SEA and inverse matrix TPA was proposed by the authors in the past studies, and the validity of this method was shown by the numerical method. However, it is necessary to extend to the real world in order to realize utilization of this comparison method. In this paper, the method is validated through experimental analyses, using a simple structure consisting of two frames. As a result, contribution rates from a power source, the SEA and TPA results are quantitatively similar less than 450 Hz.

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When an elevator rope for a high-rise building is forcibly excited by the displacements of the building induced by wind forces and/or by long-period ground motion, rope displacement becomes large even if the ground acceleration and the buildings acceleration is small. Vibration suppressor is used to change natural frequency of an elevator rope, and to avoid resonance. The elevator rope can be modeled with a string. However, vibration of the string which has vibration suppressor has been solved only on few conditions because of its geometric nonlinearity. In the case where the position of vibration suppressor is 1/N of the rope and the pulled position is center of the rope, no exact solution to the free vibration has yet been obtained. In this paper, an exact solution to the free vibration of this case is presented. Finite difference analyses of the rope vibration with vibration suppressor are also performed. The calculated results of the finite difference analyses correlated fairly well to the calculated results of the exact solution.

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We have to avoid the noise of the vehicle to be better safety and comforts. Therefore we often use structures which have a porous material sandwiched between a cover plate and a base plate. We deal with vibration properties of this structures using FEM and MSKE method proposed by Yamaguchi. In this report, we find out the characteristics of vibration transmission from the flat base plate to the cover plate which have inclination. We compute the responses excited not only at a point on the surface of the base plate but also all points on the surface of the base plate. When the cover plate have inclination, the porous material has the thin part and the thick part. In the thin part, the vibration transmission from the flat base plate to the cover plate is large. And in the thick part, elasticity of internal air at is lower and the vibration transmission amount is a little. When the base plate is excited from all the points on the surface, influences the thin part is large. Therefore the vibration transmission increases from the flat base plate to the cover plate which have inclination.

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In this study, an identification method of the modal properties, such as natural frequency and damping property, is proposed for a lightly damped element. First, from the real part and the imaginary part of the frequency response function, the relation between the unknown modal properties and the measured data is obtained. Then the simultaneous equation is constructed by adopting various frequencies around the interested resonance frequency. Finally, by using the least square method, the modal properties can be identifies. In the numerical example, the identification result by the proposed method is compared with the ones by the half power method or the circle fit. As the result, the accurate results can be obtained by the proposed method even if the low natural frequency and the light damping property. Then the modal properties of the free-free beam are identified by the proposed method from the experimental data. The damping property is modeled by the structural damping. The results shows that the damping property in the lower frequency range is larger than the one in the higher range, and the overall damping property can be expressed by using the damping property caused by the mass and the stiffness effects.

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The various kinds of the electric personal mobility, which is one or two-seater, are being developed all over the world. These mobilities are applied into the substantiative experiment held in the several cities in order to investigate the effectiveness and popularity. The main specification of the personal mobility is the small footprint to reduce the parking space and alleviate traffic jam. The authors are developing the personal mobility, which has a leaning mechanism to tilt the upper body for keeping the posture stabilization not only during turning motion but also on the uneven road surface. In this paper, the posture control method based on the motion model considering yaw motion is proposed to realize the desired roll angle. The effectiveness of the proposed approach is verified in the experiment.

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This paper deals with response behavior and running stability of the high-speed-moving railway vehicle subjected to seismic excitation. Railway vehicles are modeled by train set model that has 21 degree of freedom per car. The vehicles include some stoppers which modeled as a nonlinear spring in order to limit relative displacements between bodies and trucks or trucks and wheelsets. We investigated the effect of number of cars on running stability of the vehicle using modal analysis in which nonlinear restoring force of stopper is considered. Running stability of the high-speed-moving vehicle is evaluated by the risk rate of rollover of the vehicle. As the number of cars increase, running stability of the vehicle gets decrease in low frequency region. Furthermore, we propose the method of selecting some modes of vibration from all modes to construct the reduced order model of connected-vehicles. It shows that we can approximate the running stability of reduced order model regardless of the number of cars.

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The narrow space in cities, there exist a lot of roads and intersections. Because of there are many dangerous condition exists.Therefore, the prediction and commuter in small electric vehicle electric vehicle as the spread of urban area. The purpose of this research is slope stability, freezing road surface in urban areas, to develop the control method can be lowered. Slip control is carried out by ABS and regenerative braking force control, to improve the safety of the SEV. Because ABS can't put ABS which is a key control system of slipping control in a general vehicle on the small sized electric vehicle. Therefore the drive system of done purpose which achieves SEV smaller than inn wheel motor Thought control system for frozen in the ramp surface to realize the slip control. Will be carried out simulation and verification by model experiment. 4 wheel model with two wheel model, state feedback control, and to clarify the problem of robustness, etc

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Due to the small and slippery road condition, driving in urban area can be dangerous for most vehicles because the tire will be easily slipped. However, the risk can be reduced if the vehicles have improved performance and controllability. Here, 4 Wheel Steering (4WS) Electric Vehicle (EV) control for driving is addressed as a solution for the problem. We proposed the Intelligence Steering Control System (ISCS) on 4WS Small Electric Vehicle (SEV). ISCS is a system that will automatically change the vehicle condition to assist the driver. ISCS will compare the drivers demand to the dynamics of SEV and the circumstances around the vehicle, road conditions and vehicle stability. Then, ISCS will control all 4 wheels driving or braking torque and steering angle independently. This enables the vehicle to move on its safest condition. In this paper, we reported the first step of ISCS where it control a SEV in parallel steer driving. In parallel steer driving, the tires will be in the same direction but with different angle. SEV will make a turning based on the difference between front and rear tire angles. For the results, we proved that the usage of 4WS SEV can increase the cornering performance without affecting its stability.

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Concern over fuel consumption and ride comfort of a vehicle has been increasing in the recent years. Furthermore, environmental impact of the petroleum-based transportation infrastructure, along with the peak oil, has led to renewed interest in an electric transportation infrastructure. The problem with the electric vehicle in the market now is that the angle of cornering is not small enough to be fully used in narrow road. This research will explain about motion characteristic of rear wheel steering small Electric Vehicle (EV). The difference in torque from both rear wheel is used to control the steering of the vehicle and thus give more freedom on the maneuvering of the vehicle. This will improve the cornering of the vehicle and has the advantage of moving easily in a small space. In this research, the first simulation is to know the basic of this mechanism which is different amount of torque input is given in the same direction while the second simulation process is to know the effect of ratio of torque difference to the effectiveness of vehicle steering.

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Axle weighing system measures axle weights of in-motion vehicles. Mass estimation methods have been studied for estimating axle weights by processing the weight signal to improve the accuracy of measured axle weights. The method has been applied to in-motion vehicles at the velocity of less than 15 km/h and axle weights have been obtained in high accuracy. However, the examination of the accuracy of estimated axle weights of in-motion vehicles with higher velocity has not yet completed. To examine and improve the accuracy of the estimated axle weight, miniature models have been developed. Through the experiments using these miniature models, motion data of vehicle body and weight signals have been obtained when the miniature instrumented vehicle passes on the weighbridge in various situations. Also, we have tried to apply the estimation method to the obtained weight signals. In this paper, we describe the basic idea of the method we have proposed, the development of the miniature models and the results of applying the estimation method.

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In this report, the nonlinearity of the grip limit with respect to the normal load to the tire is introduced, and the normal load distribution control is integrated with the steering and the traction/braking distribution. The effect of the load distribution is demonstrated through the numerical examples of the optimum integrated control. For the normal load distribution, the roll rigidity distribution or the full active suspension is assumed.

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This paper presents HILS (Hardware In the Loop Simulation) for verification of a platoon longitudinal control. The main objective is to take into account the influence of a distance sensor in real world like delay, noise and so on. In this HILS, vehicle motion is calculated by simulation model. It outputs a relative position of following cars with the leading car, and the motor controllers manipulate the position of sliders, that play a role of following cars, to correspond to the relative position. A distance sensor equipped with the slider measures the distance with a front slider and outputs it to platoon longitudinal control. This control calculates a driving force to follow a target vehiclar gap and outputs it to the vehicle simulation model.

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As for making formed sheet materials with relatively high out-of-plane bending stiffness, Nagasawa et al.(2009, 2011) investigated the stability properties of the cut profile of stacked resin and paperboard sheets. It was discussed that regardless the cutting process, the cut profile properties were influenced by the shape of the cutting edge and the tool clearance. However, the collision and friction response of the contacting surface of a sheet being fed has not been discussed regarding its profile shape. Knowing the different profile shapes (wear-burr) obtained by several cutting parameters, as well as being able to specify the dynamic sliding motion for the sheet's wear-burr profile, is necessary when determining and stabilizing failures at the time of feeding. Therefore, the objective of this work is to find a simple measurement method to specify the dynamic behavior of the profile of a PET sheet when it collides after sliding over an inclined surface. The 0.5mm thickness PET sheets that have been processed leaving a sheared profile are thrown gently to slide over a guided 45 degree slope that is set to collide against an ABS counter plate. This counter plate resisters the collision using an AE sensor that attempts to measure the impact and the sliding motion of either the wear side or the burr side of the sheet profile.

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A flexible string is used at various places. Typical examples are a cable for power transmission and communication and a wire for cranes and elevators. In addition, there are the uses such as a fly-fishing line, a rope for mountain climbing and a mowing machine to cut turf by turning a nylon string. In the past study, a string pendulum was paid attention as the basic motion of the string. An analysis model of the string pendulum was made by multi-body dynamics and the behavior of the string pendulum was clarified. However, axial elongation was not considered. In fact, the string extends in the axial direction by the mass of itself and the external force and it is expected that the behavior of the string is affected by the axial elongation. Therefore, it is thought that it is necessary to carry out numerical simulation in consideration of the axial elongation in order to grasp the behavior of the string more exactly. In this study, an analysis model considering axial elongation is made and appropriateness of the modeling is verified by comparing an experiment result and an analysis result. And characteristics of the behavior of the string when the string extends in the axial direction are clarified.

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This paper considers tensegrity structures constructed from a repetition of simple basic units. Considering to design plate-type structures, we choose a tensegrity prism as a unit. Connectivity matrix plays a central role in analysis and design of tensegrity structures. This paper provides a systematic way to construct the connectivity matrices of tensegrity structures constructed from a repetition of the tensegrity prisms. Number of the units and node location (shape) can also be chosen arbitrary. As an application of the connectivity matrix, a dynamical simulation of a tensegrity prism plate is shown.

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This report is about response analysis using Statistical Energy Analysis (SEA) with FEM for two panels connected in L-shape. Viscoelastic damping materials are laminated on the panels. One of the panels has a bead formed in circular ring. Usually, modal damping is influenced by shape of panels and forms of the connection. Therefore, to consider coupling in damping between substructures, we proposed calculation method using FEM and MSE (Modal Strain Energy) method to identify internal loss factors. We changed the inner diameter of the circular ring. As a result, we could identify SEA parameters in high precision. And the proposed SEA enables us to improve not only precision in high frequency but also precision in low frequency.

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In this paper, dynamic responses of contact lenses are investigated. Dynamic restoring force of contact lenses were measured using Levitation Mass Method (LMM) proposed by Fujii. This sophisticated experimental system has a block, which can smoothly travel along a guide due to a pneumatic linear bearing. Thus, the block is levitated by air film at the interfaces between the block and the guide. By this system, the block can move toward z direction under low friction. Therefore, we carry out numerical analysis of dynamic responses for the lenses under same conditions with the experiment. Contact lens is modeled using elements for nonlinear complex restoring force. This nonlinear complex element is connected to the levitated block, which is modeled by three-dimensional finite elements. Like the experiment, initial velocities are given to and hysteresis curves are computed. Nonlinear complex spring constants are identified by the obtained curves. We also calculate the time histories of displacement, velocity, and acceleration by the analysis.

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