This paper describes acquisition of 3D data and the light receiving intensity data on reflecting points at the same time by 3D SOKUIKI sensor module used roundly swinging mechanism. We determined 3D data and the light receiving intensity data on the reflecting points token by the sensor module corresponded with image of real space. We also determined calculated reflection coefficient data in mind diffusion of light on laser beam by distance from sensor module to the reflecting points, compared to raw light receiving intensity data by optical sensor input of the sensor module.

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This paper describes our image stabilization system. We use a small-sized humanoid robot to simulate a person who captures visual information of a distant site and aim to develop an image stabilization system for a small-sized humanoid robot. This system has a 3-dimensional motion sensor to obtain rotational motion of a camera and also optical flow process to obtain translational motion. We extracted optical flow information to obtain translational motion higher accuracy. The experimental results show that our image stabilization system can successfully stabilize the image from the robot.

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The industrial robot succeeded in uninhabited shut space (closed system) surrounded with a fence. The air that is the uninhabited open space (open system) is also a place of convincing activity of the robots. In the 21st century, it's times to do infrastructure smaller scale like the mobile telephone which installed a base station thinly, and used the air at the minimum not the century when a road and a tunnel, a bridge used vast energy to infrastructure. Aerial use for transportation is promising in the future, and development of aerial Robotics is expected of the transportation of a material using 25% of all energy now. In this paper, it is introduced possibility of aerial Robotics and challenges of the past research and development.

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As for the 6-legs-robot, a static walking is always achieved, it is possible to walk. Here, the loss of the leg is thought by some circumstances in the disaster support robot while walking of the disaster support. In the case, it is not possible to keep walking by a usual walking algorithm. Then, the walking algorithm at the failures up to two was examined.

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In late years, with development of fMRI, PET, NIRS, brain function eld analysis attracts big attention by the development of the highly advanced functional analysis such as a sense organ about sight function, memory or recognition in somatic sensation eld analysis, especially a signicant study example about BMI (Brain-machine Interface) by MAMITANI (ART) is suggested. However, it is known that there have problems for the use of a direct input support device because the brain waves' measurement require considerable time and a device which large-scaled and large-amount such as the MRI. And, this analysis becomes dificult by irrationality brain waves coexisting to brain waves. To distinguish from the change of brain waves in real time, I suggest a method of extract and distinguish a characteristic as a static pattern that has plasticity in discrimination time around 50ms〜100ms from brain wave's change caused by ocular movement.

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Metal spinning is a plastic forming process that forms sheet or tube metal fixed to a rotating mandrel by forcing roller tools. Products formed by metal spinning have been inherently limited to straight-axis and circular-sectional shapes. In this study, we succeeded in making curved-axis and non-axisymmetric shells by synchronizing the roller motion in the axial and radial direction with the rotaion of the spindle axis, and without using forming dies. A numerically-controlled spinning machine moves the spherical head tool along the trajectory which is calculated from the desired shape considering contact with the tool. Products are experimentally formed from aluminum sheet.

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In order to understand the influence of motion cues on human pilot's control characteristics in a flying airplane, this study carries out the fundamental experiments in which the pilot compensates the pitch angle error from references command. Therefore, a flight angular acceleration of pitch gives to the pilot from moving based flight simulator. This experimental results show that the task performances and the control behavior of the pilot are changed a little by the motion cues.

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This study investigated the relationship among natural colors, aroma essences and human Kansei, and considered how people interpret the nature colors and the aroma essences for creating a healing space. To investigate the relationship, the electroencephalogram (EEG) and Kansei assessment were used. The EEG was measured with watching images of nature colors and smelling aroma essences. After the measurement, the questionnaire was practiced about feeling nature colors and aroma essences, and the factor score was analyzed.

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It is well known that a rotor supported by journal bearings has a risk of whirl in high speed rotaional regions. Especially in case of a light weight rotor and/or a short span bearing system, it is important to consider not only the cylindrical mode but also the conical mode stability. This paper describes the effect of conical mode vibration on the stability threshold of herringbone grooved aerodynamic journal bearings. Results show that the stability threshold increased as the offset value of vibration center increased, and the conical stability lower than cylindrical stability in the short span bearing system.

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The shaping of the spur gear by expanding the inner diameter was studied. That is the workpiece is set its inner diameter to the front part of the stepped mandrel, which is placed the expansion of its inner diameter, by passing through the rear part of the mandrel. The specification of the gear is as follows: module m=1.0mm, number of teeth z=26, pressure angle α=20°, whole depth h=2.25mm, addendum modification x=0.25. Criterion for the shaping of complete teeth is discussed in terms of reduction in area and expanding of the inner diameter of workpiece. It is shown that the reduction in area for shaping the complete teethed gears 8%. The required pressure of punch annd stepped mandrel for shaping is far below the strength of the punch and mandrel materials.

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Many machines depend on the rotary machines such as engines and motors for the power. However, stress analysis and intensity analysis of the solid of revolution is important, because the severity of rotary machine increases. In this study, rotating disk models having crack as defect was made from polycarbonate material, and the rotation axis was made eccentric. And the stress freezing experiment is conducted; the observation of stress around a crack tip caused by the roation in a stationary state is enables. By doing the analysis of the state of stress riser's stress, the relation between stress around a crack tip and amount of eccentric is clarified. The evaluation is obtained by the stress intensity factor calculated from caustics method.

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High polymer materials are used in various fields, they will be expected to increase use of severe conditions in the future. However, high polymer materials have the feature that the characteristic is easy to change by the use conditions. Therefore, to expand the range of use of high polymer materials further, it is necessary to understand the fracture characteristic by the temperature dependence. In this study, specimens are three kinds of high polymer materials. The crack model assumed V-notch. The experiment temperatures were assumed to be a room temperature, 0, -10, -20, -30, -40 and -50℃. The dynamic stress intensity factor K_1 was determined by using caustics method and impact three-point bending test. The strangth of materials in low temperature was evaluated by calculating K_1. As a result, with a fall of the temperature, the maximum value of K_1 decreased in all materials.

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Aluminum nitride - aluminum composite disk was slid against Si_3N_4 pin in ethanol to evaluate the wear resistance. The wear resistance of the aluminum nitride - aluminum composite was much higher than that of aluminum metal. Worn surface indicated that the amount of aluminum, which adhered from the composite disk to Si_3N_4 pin, was much less than that from aluminum metal disk. The wear of the composite with high AlN content was lower than that with low AlN content.

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In Japan Atomic Energy Agency (JAEA), a study on flow induced vibration in the primary cooling system of Japan Sodium cooled Fast Reactor (JSFR) consisting of large diameter pipe and pipe elbow with short curvature radius ("Short-elbow") has been conducted. Structural integrity of the pipe due to the flow instability around the short-elbow is concerned in the design study of JSFR. In this paper, background of the study and outline of the numerical investigations for the structural integrity of the pipe elbow are briefly described. Numerical results at Re=5x10^5 and Re=3.7x10^6 in the short-elbow are presented as a verification study of the in-house LES code named as MUGTHES. Flow characteristics around the elbow exit and influence of the inlet boundary condition on them are discussed.

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Recently, the distance between an elbow and a flowmeter in a flow loop is reduced because industrial plants are more and more compact. The performed velocity profile is caused by an elbow. In this case, error of flowmeter may be not negligible due to the deformation of the velocity profile. To estimate the error of measurement by ultrasonic flowmeter downstream of elbow, this study investigated the velocity distribution by using PIV. As a result, the velocity distribution downstream of elbow was developed after the distance x/D=20. And, the error of measurement by ultrasonic flowmeter based on the y-axis distribution (including the curvature of the elbow) was smaller than the z-axis distribution.

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A casing wall was perforated at the rotor section with a view to improving the performance in the partial capacity region of an axial-flow fan. The holes introduced were in three annular rows at different axial locations; (1) at the leading edge, (2) at mid-chord, and (3) at the trailing edge of rotor blades. Combining (2) and (3) simultaneously led to a maximum expansion of the stall margin. An opening area ratio was found in which the stall margin was maximized without any deterioration of design point efficiency.

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The aim of this study is to reveal the basic flow characteristics of the free surface vortex. In order to obtain the downward velocity along the vortex, the flow field at the vertical cross section was measured by PIV. The position of gas core was simultaneously taken by a camera. Because the position of the gas core changed with the flow rate, the relative relation between the vortex and the fixed laser sheet or the measurement plane of the velocity changed also. Therefore, the velocity field obtained in the study was discussed with its relative position to the surface vortex.

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For predicting the hand force in swimming, the quasi-steady-state approach led to errors in predicting the fluid forces acting on a hand in unsteady conditions. The actual motion of a hand in swimming is obviously unsteady, and the time-dependent fluid forces have to be taken into account. The purpose of this study is to investigate the relationship between unsteady fluid forces and vortex behaviors for a three-dimensional airfoil during the pitching motion. In this study, the flow visualization technique was used to aid in understanding the flow field in the near field of the airfoil edge for the wind tunnel test. The unsteady fluid forces were affected by the behavior of vortices shedding from the airfoil edge during the pitching motion, and the flow structure due to the vortex behavior was strongly affected by the reduced frequency.

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To investigate the dynamic behavior of vortex shedding from a discoid airfoil, which simulates a hand of swimmer, we made an experiment using a wind tunnel. The structure of flow from the pitching airfoil is measured by particle image velocimetry (PIV). It was cleared that the reduced frequency k and the amplitude of pitching motion affect of the flow structure. The flow structures due to vortex shedding from a discoid airfoil edge during the pitching motion were affected by the reduced frequency k. The effect was dependent on the reduced frequency k rather than the amplitude of pitching motion. In addition, the reduced frequency k gave more prominent effect on the velocity profiles in the wake rather than the amplitude of pitching motion.

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Analysis for natural convection between vertical parallel plates was conducted to develop a thermal insulation system. The heat transfer and fluid flow were analyzed to confirm the applicability of the present numerical computation. The optimum vent layer thickness of thermal insulation system was investigated with the numerical simulation. The vent layer size was considered along with developing the technique how to control the present thermal system by switching the vent.

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Toward the commercialization of fast reactors, adoption of fully natural circulation system is being examined as the decay heat removal system from the viewpoints of economic competitiveness and passive safety. This paper introduces a new evaluation method for hot spot in core of fast reactor under natural circulation. The new method consists of three step analyses in order to include the effects of thermal hydraulic phenomena particular to natural circulation decay heat removal, inter-assembly heat transfer and flow redistribution in fuel assemblies and in the core by buoyancy force. The method was applied to an analysis of loss-of-external-power event and the result was compared with those by a conventional method and a detailed 3D simulation. It was confirmed that the proposed method can estimate the hot spot with a resonable degree of conservativeness.

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CO_2 is recognized as one of the most suitable natural working fluid for compression heat pump to heat cold water to hot temperature region. But the coefficient of performance (COP) for cooling is not high. This is because the temperature of the working fluid discharged from compressor is so high to the heat sink that is often the outside air temperature. When a low temperature heat sink is available, cooling for the air conditioning by CO_2 heat pump can be realized. In this study, river water, underground water and ground are supposed as heat sink. When the low temperature heat sink is used and expansion at 25 C is realized, cooling COP is improved and shows the value 5.89 for single stage compression and 6.67 for two stage compression with flash cycle. These values are very close to those obtained by the conventional system that uses R410A.

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In order to develop air-conditioning system using ground heat that realize high energy efficiency and low construction cost for residence, we approach a ground coupled heat pump system utilizing direct evaporating/condensing groud heat exchangers. We researched basic operating characteristics of the system through experiment. Experimental facility consists mainly of groud heat exchangers, a ground source heat pump, and a temperature-controlled water tank for thermal loading. The ground heat exchangers are vertical copper U-tubes and have the range from 20.5 to 40.5 meters in depth below the surface. In this study, we used three 20.5m^depth ground heat exchangers and operate the system both in heat-source mode and in heat-sink mode. Thermal output from the heat pump was sufficiently stable in heat-source mode and COP was around 4. On the other hand, operation in heat-sink mode was unstable and the thermal output changed with changing suction/discharge pressure of compressor and refrigerant flow rate.

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AIST Energy Technology Research Institute (ETRI) has been demonstraing micro gas turbine co-generation system (MGT-CGS) in Sapporo City University since 2006. In 2009, we changed the schedule timer for MGT-CGS to new programmable logic controller (PLC) to improve CO_2 reduction. Input signals to PLC were temperatures inside and outside and electric powers, and output signals were relays for MGT-CGS and the heat strorage system. This paper showed some design changes to introduce instruments in the campus, some construction plans to discuss, results and interlocking process between MGT-CGS and heat strage system.

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When a phase change material (PCM) is stored in the supercooled state and is gotten to start solidification to demand, the heat of solidification of the PCM can be stored at low heat loss for a long term. Thus the influence of the mass of PCM that is filled up in a capsule on the maximum degree of supercooling was investigated using several promising PCMs to evaluate the functional utility as PCMs. As a result, it was found that the maximum degree of supercooling of erythritol or threitol was large and depended on the mass strongly, so that the two materials are useful for using supercooling phenomenon. However, it was found to be difficult to use the supercooled phenomenon of polyethylene glycol effectively because the maximum degree of supercooling of the material is small and little depends on the mass.

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Outline of the activity in the Hi-Tech Research Center, KAIT is introduced. Among the activity, field test data on a solar heated thermosyphon (TS) is described. We propose a mathematical model of simplified thermosyphon. The model gives us an overall insight into the TS system performance. Based on the model, the driving force F produced by the heat input Q_<in> and the resisntance R proportional to mean velocity were estimated as 5×10^<-4>[N] and 7.7×10^<-3>[N/(m/s)], respectively. The present simplest model estimated much smaller F compared to the one calculated using Q_<in> without losses.

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We developed a discharge nozzle for the purpose of providing a water mist appropriate to fire extinguishment under low pressure. Using the nozzle, it was confirmed that oil fires (for example, diesel spray fire, gasoline pool fire, and so on) can be extinguished. It has an apparently simple atomization mechanism, but it is not clear how the dimensions of the nozzle parts affect the spraying behavior, which is also a very important problem from industrial viewpoint. Therefore, it is difficult to verify only by experiments. In this study, we tried to suggest a simple calculation model and analyze spraying behaviors of the nozzle with CFD. The calculated values were well coincident with the experimental values.

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Velocity distributions produced by a dielectric barrier discharge plasma actuator (DBD-PA) with various shapes of electrodes were measured by using a PIV system. By using two power supplies, tangential jets with different velocity distributions in time and space were induced independently in the vicinity of the wall from electrodes. Wall-normal jets produced by a pair of facing electrodes can be inclined by colliding tangential jets with different speeds. Wall-normal jets that distributed clockwise and counterclockwise vortices can be produced alternately by applying signal packets in different phase to each of the top electrodes. The properties of the functional jets were characterized by PIV analysis.

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According to the result of remarkable increase in life expectancy, on the other hand, the needs for health in advanced age is focused on anew. Not as in conventional health check in heathcare facility, self-diagnosis method in ordinary life along objective and scientific analysis guidepost or criteria is important to hold down expense and to save the labor time for ordinary care. This study aim at constructing objective health index with the daily living action and especially from active standing posture balancing motion as an abstract case. This evaluation system consists of 4 processes, human motion modeling, model order reduction, characteristics analysis, standard index proposition, aging factor analysis. This paper show the balanced realization method is effective to reduce model order keeping characteristics of human motion. Aging depency is considered with the acceleration factor.

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In Recent developed nations, the Aging and falling birthrate is advancing rapidly. In Japan, the increasing burden rate of productive population becomes an important issue. Simultaneously, Administrative agency announced the concept of care prevention should be more introduced to prevent these problems. This study proposes self-health check system using human's gait pattern analysis as daily action. An integrated assessment index, Gait Period Assessment: GPA is proposed, which consists of Gait Period Variation Index: GPVI and Vertical Stroke Displacement Index: VSDI and Maximum Split Acceleration Index: MSAI. The age trend in Gait Pattern shows prominent more over 40's with this assessment.

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In late years, living environment changes greatly, and people feeling stress to mind and body increase, and it is taken up as an important social problem. This study conduct to develop the device which promotes stress relaxation which I give vibration stimulation load of the machine to the foot bottom rank with the transverse presentation posture that it is thought that there is an effect to reduce stress (for example, bloodstream obstruction or outbreak of the thrombosis) to the body to have cause of environment working with constant posture for a long time. It was confirmed that the stimulus signal that built in the 1/f fluctuation signal at the vibratory stimulation from current study results was predominance more than white noise, constant vibration, and 1/f^n fluctuation signal by the temperature maintenance and other inspection items. This report burdened the stimulation signal which paid attention to an ingredient in a super long period of the fluctuation effect. It was confirmed that a super long period change stimulation brings the effect that is similar to a 1/f fluctuation by comparison inspection about a stress relaxation effect with the conventional case that I gave a fluctuation signal. I consider an effect to give to the stress relaxation of the fluctuation signal.

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In this paper, we propose a pair of step-climbing units for a manual wheelchair. The user is such a person who has no disabled upper limbs and is able to raise casters attached in from of the manual wheelchair. Each step-climbing unit comprises two actuators and has two degrees of freedom: a prismatic joint and a rotational joint. We discuss the motions of climbing a step using the units. Experimental results confirm the design's effectiveness.

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We have developed a non-contacting type centrifugal blood pump with hydrodynamic bearings. The purpose of this study is development and hemocompatibility evaluation of a circulatory assist pump with hydrodynamic bearings. In the test, we evaluated different eye hole diameters of the closed impeller. Under the condition of 4L/min and 200mmHg, the upper bearing gap became more than 100μm, and the hemolysis index became equivalent to that of a commercial pump.

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In this study, the enclosed-impeller type axial flow blood pump has been research and developed. This pump is mechanism to drain by turning the spindle rotor which became at one with an impeller. High efficiency, the high durability, miniaturization are demanded from the motor which is an actuator. However, magnetic flux became overcrowled in the central part of the tooth of stator, and, with the current motor, decrease of the torque was suggested. Therefore I report this article because I performed reduction of the magnetic induction in the central part of the stator and improvement of the torque by analysis. If magnetic flux is overcrowded, magnetic flux is hard to come to flow through the stator made of electromagnetic steel sheets. Therefore magnetic induction decreased by changing the shape of the tooth of stator. By this, magnetic flux was easy to come to flow, and about 17% torque improved.

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The maglev technology offers long lifetime and better biocompatibility of the blood pump by eliminating the mechanical contact components from the device. We have developed a miniaturized maglev blood pump for an artificial heart for neonate and infant. Target length and diameter of the designed pump are 33.4 mm and 24 mm, respectively. The pump consists of a self bearing motor and a levitated rotor impeller. The self bearing motor which suspends the rotor impeller in the axial direction, consists of electromagnetic cores, two poles permanent magnets on the both surface, and electromagnet coils for rotor position, rotation and tilt control. The self bearing motor was designed based on magnetic field analysis. Experimental results indicate sufficient magnetic suspension performance of magnetically levitated motor.

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A 5-DOF self-bearing motor has been proposed to achieve a compact active magnetic bearing (AMB) system. The 5-DOF self-bearing motor possesses the functions of a motor, two raidal AMBs, and an axial AMB. Therefore, it is possible to downsize the AMB system with maintaining high performance. In this paper, a 5-DOF self-bearing motor is analyzed to realize the further downsizing for the application of an artificial heart using 3 dimensional finite element method. The analytic condition is set that the motor torque is 30mNm, the control force is quintuple of the rotor gravity (5G), and the diameter of the outer rotor is 50mm. The results showed the feasibility of the downsizing of the propose outer rotor type 5-DOF self-bearing motor.

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The relationship between surface roughness and shear stress was quantified by computational fluid dynamic analysis to clarify the flow behavior in the rotational shear stressor where the surface roughness was approximately 2μm on the surface of inner stator with the rotational speed of 1,000 rpm where hemolysis level doubled in comparison with smooth surface stator. As a result, it was found that the maximum shear stress caused on the surface of the inner stator by the surface roughness, especially around the edge of the inner stator. Quantification of the relationship between shear stress and hemolysis was magnified by the threshold level that limited low shear stress effect on hemolysis. It was accurately revealed by the analysis with finer mesh whose shear stress has a certain amount of distribution.

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It is important to clarify the relationship between the hemolysis level and degree of surface roughness on the metal surface under blood shear fields. From our previous study using a rotational shear stressor, we have obtained the following results; the hemolysis level was increased between Ra 0.1 and 0.8μm, and showed constant over 0.8μm under laminar shear fields. Especially between Ra 0.6 and 0.8μm, the level of hemolysis rapidly increased and suggested that the increased hemolysis was related to the shear stress due to the surface roughness. However we have not yet measured the increasing shear stress amount with the stressor. In this study, we tried to quantify the shear stress level using viscous test blood with dextran solution.

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In this research, aiming at the highly efficient small artificial lung, the membrane area was made fixed in 0.3m^2, and housing form was optimized. Minimization of the standard deviation of the blood flow velocity in the hollow fiber membrane(sddv) as improvenent in gas exchange performance, minimization of blood pressure(pdrop) and minimization of a blood fill ration(pv) as biocompatibility, and minimization of the domain of 0.5 or less mm/s of the blood flow velocities(v5mm ) as reduction of thrombosis were set up in objective functions. In addition, calculating for the relation between objective functions and design variables by multiple linear regression analysis using many solutions produced inevitably, it is thought that will get new indexs of a future design. The excellent result was able to be obtained from the analyzed result on optimization of the artificial lung. Moreover, it was suggested from the relation between objective functions and design variables that the volume of a hollow fiber membrane is the most important.

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