Japan is one of the most advanced countries in earthquake technology. Many isolation systems are widely used in large-scale structures. Application of the seismic isolation systems to the structure has been expected in order to enhance seismic safety. When seismic PRA is applied to seismic isolation system, large-scale ground motion should be considered. Rubber bearings have nonlinear characteristics in case of large deformation. In addition, the horizontal nonlinear characteristics depend on vertical load. Therefore, it is important to consider this nonlinearity and coupling effect between horizontal and vertical deformation. This paper describes results of sensitivity analysis of the advanced seismic isolation system. The sensitivity analysis, parameter of the rubber bearings, the oil dampers and the building were fluctuated, and influence of dispersion of these parameters upon response of building was investigated.

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In this paper, the authors have developed a new type of horizontal seismic isolation system which has large effect of vibration isolation for ordinary earthquakes and suppresses the resonance of the isolation system due to long-period seismic ground motions. This seismic isolation system is composed of coil spring and two slide rails. This seismic isolation is added a large frictional force beforehand. Frictional force is used to suppress the resonance of the seismic isolation system. The trial seismic isolation table was made, and the effects of vibration suppression of the isolation table were discussed experimentally and numerically.

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In the great earthquake, such as the Great East Japan Earthquake March 11 2011, period occurred to long-period ground motion of more than 2 seconds, and generates the damage over a wide range. Frequency of long-period ground motion is close to frequency of tall building, so tall building is caused resonance by long-period ground motion. Then resonance causes to tip over medical equipment and computer server. Therefore, development of new small seismic isolation device for installed into buildings in preventing earthquake damage is required. This study uses the bending stiffness soft high damping elastomer that has effect that reduces response displacement according to long-period ground motion. The development of small three-dimensional seismic isolation equipment which has been subjected to torsion prevention measure and used the bending stiffness soft high damping elastomer is intended to reduce the damage caused by earthquake. Height of experiment device is as low as 282 mm due to practical use, and sets to 500 × 500 mm in order to ensure the space of response displacement. Further, the bending rigidity is obtained by CAE analysis, and then the shape of the elastomer was determined dimensions. The experimental device is used the low friction roller and the soft bending stiffness high damping elastomer in the supporting the device in seismic isolation of the horizontal direction, and is used a friction plate of magnet and the displacement friction force in the compression spring comes in seismic isolation of the vertical direction. This study is an experimental device on an earthquake wave reproduction device and test it using a real earthquake wave pattern and confirm the performance of the experimental device, and the study contents make an analysis model more and analyze simulation and, in what it compares with the laboratory finding of the experimental device, check the effectiveness of the analysis model and confirm the performance of the device caused by the real earthquake by the simulation analysis.

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We made a small base isolation system using friction bearings made of SUS304, that used for heavy structures. Characteristics of this system with change of loading based on vibration experiments were investigated. Increasing the loading on this system, a natural frequency and damping ratio indicated increase. Especially in case using only friction bearings with a marble plate, the damping ratio became conditions of over damping. A peak amplitude ratio divided the response by the input also was increased. And a friction coefficient was measured by a static loading test, it was increased depending on the load. Results from numerical analyses using parameters estimated by experiments, the peak response amplitude increasing the friction coefficient do not change in case that the natural frequency is fixed. However the response was amplified by resonance in case that the natural frequency increases with the load. It is important to fix the natural frequency.

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A study was conducted on special cross railed seismic isolation system to analyze the relation between the response displacement and damping performance. This paper proposes a special seismic isolation system featuring S-curved gr bearing. The study showed the performance of response displacement of S-curved seismic isolation system is proporti to friction coefficient. Further vibration test yielded response acceleration rate is proportional to response displacemen which will allow smaller seismic system to handle wider variety of earthquakes.

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Base isolation system will be aggressively applied to not only architectural and civil structures but also various structures, because the effectiveness on seismic safety had been demonstrated again in the Great East Japan Earthquake. In generally, although the base isolation system is divided into laminated rubber bearing type and friction sliding bearing type. In the case of former type, shape factor, maximum or minimum outer shape and so on are restricted by the material characteristics in visco-elastic material. In this study, the research and development of laminated type base isolation device using urethane elastomer has been carried out to upgrade a seismic safety for various structures. The fundamental characteristics have been investigated from several loading test by using various experimental devices, and the design formula for the stiffness and equivalent damping coefficient is formulated as an approximate expression of mechanical characteristics until now. Moreover, the experimental examination for aged deterioration in the urethane material has been continuously carried out. As the results, it was confirmed that the laminated type seismic isolation device using urethane elastomer is possible to develop as a practicable device from the stable mechanical properties as considering in design step.

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The authors proposed a unique type of semiactive damper that utilizes electromagnetic induction of a fluid in previous paper. But it was not enough to act an effect of electromagnetic induction because of a weak magnetic flux density. In this paper Halbach magnetic arrays is used for the damper in order to improve the effect. The damper consists of a cylinder, a piston, a by-pass pipe, tubes, tube couplings, electrodes, and trapezoid rare-earth magnets. A high conductive polymer fluid is filled in the cylinder, the by-pass pipe and the tube. Two electrodes are fixed inside the by-pass pipe, and faced. Eight magnets are set up as an octagonal Halbach array around the by-pass pipe, and each array units are installed in series. The magnetic field of the by-pass pipe is analyzed by FEM, and measured. The maximum magnetic flux density inside the by-pass pipe is about 0.9 T, and larger than the previous type. Resisting force characteristics of the damper acting the Lorenz force are measured when a voltage of the electrodes is applied in cross at the magnetic flux. Finally the effect of the electromagnetic induction is confirmed experimentally.

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This study deals with the rocking motion of cabinets. In power plants or chemical plants, there are many control cabinets containing important electronic devices. In many cases, these cabinets are put directly on the floor. Thus, it is thought that in the worst case, cabinets may turn over by rocking motion during earthquakes. Therefore, it is needed to develop rocking motion suppression methods. In this study, adjacent cabinets are connected with an elasto-plastic damper. The elasto-plastic damper has a bilinear hysteretic characteristic and can absorb the energy of earthquake inputs. Firstly, we evaluate the maximum rocking angle of single cabinet for seismic wave input, and clarify the characteristics of rocking motion. Next, we simulate connected cabinets under the same conditions and compare the maximum rocking angle. In these simulations, it is assumed that cabinets do not collide with each other. And we set parameters of elasto-plastic damper arbitrarily and analyze by changing the yield load or aspect ratio of one cabinet.

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This paper deals with a high energy absorbing seismic tie, which is energy absorbing device installed between boiler and its support structure. In our previous paper, I-section seismic tie as new type has been developed by optimizing the design parameters (sectional height, web thickness and flange thickness), changing its material from current carbon steel SS400 to low yield strength steel LY225. Cyclic load tests using 1/3 scale models of the tie have been done to verify energy absorption of the high energy absorbing seismic tie. In this paper, vibration reduction effects for thermal power boiler structure with the high energy absorbing seismic ties are examined by time history analysis using an analytical model which simulates boiler structural vibration characteristics.

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The purpose of this study is to develop a three-dimensional passive dynamic damper using springs with high damping material to reduce multiple vibration modes of piping systems. In this paper, first, studies of theory for design of a three-dimensional passive dynamic damper are described. As a result, multiple TMD theory is applied as the best design method of the three-dimensional passive dynamic damper. Next, vibration tests using a small dynamic damper model with high damping springs and a steel pipe model are performed in order to investigate effects of vibration reductions of the dynamic damper model. As a result, the damping characteristics of the steel pipe model are confirmed to be greatly improved by using the dynamic damper model. Further, seismic response analyses are performed in order to investigate effects of damping characteristics of the vibration tests model on the seismic responses of the pipe model. Further, comparison of the seismic responses of the vibration models with the optimum damping and damping using high damping spring are performed.

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Acceleration in various directions that occur during running of the ambulance adversely affects the sickness and wound people. Therefore, there is a need for devices to suppress the acceleration in front and back vertical direction. In order to prevent the progression of the disease and of the winding's disease, the study is aimed at the development of the acceleration reduction device corresponding to the bed of the ambulance. In particular, I describe the acceleration reduction in front and back direction. A Pendulum tilt chassis is used to reduce the acceleration in front-and-back direction. In addition, a variable friction damper is attached to it. The variable friction damper is a sliding friction mechanism utilizing the difference in adsorption force of the magnets. Because adsorption force is nothing when the magnet to slide over the non-magnetic material, sliding friction force is also reduced. Because adsorption force is strong that compared to the non-magnetic material when the magnet to slide over the magnetic material, sliding friction force is also increased. The results of the numerical analysis using the analysis model, it was confirmed that it can be kept to about half the acceleration.

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The present paper describes damping effect of the impact damper having two vibrators on a floor. Response of the damper is investigated and the optimal natural frequency rates of the vibrators are calculated based on numerical simulations. And the vibrator of the damper and the floor due to floor impact is observed by a high speed camera. Some important results of the study are as follows: 1) Optimum value of natural frequency rates is combination that vibrators collide head-on and collide many times. 2) Effect of the damper for impulse force is clearly observed. And damping effect is in proportion to impact force. 3) Effect of the damper for step force is limited by an additional mass corresponding to the step force on the floor. The natural frequency rates do not become optimal and the number of collisions between two vibrator decreases when the added mass is heavy.

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Every year, many earthquakes occur in Japan. Many high rise structures which are in a long distance from the hypocenter of the earthquake resonate with the long period ground motion. Recently, many structures require countermeasure for long period ground motion. Various viscous dampers have been developed and applied to actual structures to suppress vibration response. However, the vibration control performance decreases with the long duration time of earthquake because of a temperature rise of the viscous material. Therefore, there is concern that these viscous dampers can not suppress vibration response in case of long period ground motion. In order to solve this problem, a viscous-friction damper in series is proposed in this study. Then, in this hybrid damper, the friction damper can absorb vibration energy as well in case of the long period ground motion. In this paper, seismic response analysis is conducted to confirm performance of hybrid damper.

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In recent years, because of demand for reconstruction of buildings that were constructed in high economic growth period (1960s), demolition work is carried out frequently in many places in Japan. Heavy equipment such as excavators is commonly used to the demolition work. However, the excavators generate uncomfortable vibration to neighbors. Therefore, the purpose of this study is research and development of vibration control device for excavators. A Tuned Mass Damper (TMD) is most commonly used for vibration control. Usually the TMD is tuned by using optimal design formula depending on the weight and the stiffness of the control target. However the tuning violated if the parameters of the control target are changes. In order to solve this problem, a Multiple Tuned Mass Damper (MTMD) is applied in this study. The MTMD consists of a primary mass and a secondary mass. The secondary mass is placed on the primary mass in series. Applying the secondary mass can widen the effective target frequency range of vibration control. This paper fabricated a prototype of MTMD and its performance was verified experimentally. As a result, it is confirmed that the prototype of MTMD has good performance in vibration control for excavator.

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This paper presents a passive dynamic vibration absorber using a DC motor and an LR circuit instead of a spring and a dashpot. The combination of the DC motor and LR circuit equivalently works as a mechanical spring and a dashpot. The dynamic vibration absorber using the DC motor and LR circuit enables tuning of the natural frequency and damping ratio with ease. This paper describes the derivation of the governing equations of the proposed dynamic vibration absorber, derivation of an equivalent mechanical model of the proposed method and simulations.

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In this study, we propose a system to reduce the displacement of the tuned mass damper (TMD) with lever and pendulum mechanism that was placed in the roof for seismic response control of high-rise buildings. This is a displacement magnifying mechanism attaching the weight and lever in the horizontal direction in the space between the roof and TMD. In particular, in this paper, the optimal tuning method of the dynamic mass(D.M.) is examined, and by applying this control system to the single degree of freedom (SDOF) building and the multi-degree of freedom (MDOF) buildings as shown in Figs.l and 2 subjected to long-period earthquake motions for response control, its effectiveness is examined.

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Friction and wear arise in contact sliding parts of machines, increases in wear and deformation of the sliding parts caused by frictional heat. Induce mechanical failure lubricants are used to prevent these problems, but lubricant is evaporated or decomposed by frictional heat. In recent years, ionic liquids are attracting much attention as new lubricants. Ionic liquids have various non-conventional physical and chemical characteristics. We used three types of imidazolium ionic liquids: BMI-PF_6 (1-Butyl-3-methylimidazolium hexafluorophosphate), HMI-PF_6 (1-Hexyl-3-methylimidazolium hexafluorophosphate), OMI-PF_6 (1-Octyl-3-methylimidazolium hexafluorophosphate) with different alkyl chain length. They were coated on Si substrates with SiO_2 layer on the surface. We measured frictional force between the substrate coated with the ionic liquid and AFM (atomic force microscope) conductive tip as voltages were applied between them. It was confirmed that frictional force increased by applying voltages. The sample coated with HMI-PF_6 exhibited the largest increase in frictional force when voltages are applied.

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A flame combustion method enables the synthesis of diamond using acetylene-oxygen in ambient atmosphere. It has various advantages over other methods. In this method, during cooling, most diamond films delaminate as a result of thermal stress. We previously synthesized diamond films on a Mo substrate surface by the flame combustion method. To prevent diamond film delamination for the synthesis of good diamond films, a three-step synthesis method was proposed. In this study, to reduce the surface roughness of diamond films and to achieve good adhesion on the Mo substrate, diamond films were synthesized by flame combustion with the three-step synthesis method. The diamond seed particles as growth nuclei for the diamond synthesis were changed to small. Furthermore, the flow ratio of oxygen flow rate to acetylene flow rate and synthesis time zone were carefully varied during the three-step synthesis method. To investigate the influence factors of the surface roughness of synthesized diamond films, synthesized films were observed. The diamond seed particles size, the flow ratio and synthesis time zone affected the surface roughness.

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As development of micro electro mechanical systems (MEMS) technology, microforming is gaining attention. And, lubricant-free microforming process is a strong demand. Due to the low effect of lubricant in microscale dimensions, the tribological issues in microforming confronts with further severe problems to enhance the performance of microdie surface. So an approach to enhance the tribological performance is applying the micro-textured structure to the surface of microdie with expecting the function of wear debris ejecting effect. Micro-texturing was realized by using stainless steel wire mesh as a masking during the ionized vapored deposition of diamond-like carbon (DLC) coating film. To characterize the basic tribological properties of micro-textured DLC films under dry condition, the ball-on-disk type tribology test was carried out. In view of the confirming wear debris ejecting effect, titanium oxide nanoparticles were intentionally added as artificial wear debris. As results, the micro-textured DLC film showed low coefficient of friction, while the conventional non-textured DLC films showed the significantly large value. Wear track observation after the friction tests revealed that the stable tribological properties of textured DLC films were attributed to the promotion of wear debris ejection, which can prevent the ploughing and adhesion inside the apparent area of contact.

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Composite materials based on a molybdenum disulfide (MoS_2) and metal is a candidate to improve its lubricating property under dry or vacuum condition. However, since a metal sintering or dissolution temperature is higher than the oxidization temperature (623 K) of MoS_2, the lubricating property of conventionally-prepared MoS_2 composite will be lost. In this research, we fabricated the MoS_2-dispersed Cu composite material by Compression Shearing Method at Room Temperature (COSME-RT), which is the dynamic powder molding technique wothout heating process. Tribological and mechanical properties of novel MoS_2-dispersed composites by COSME-RT were reported.

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Recently, the self-motion mechanism has attracted attention as a new motion mechanism. By realizing micro self-moving bodies which don't need energy supply from the outside and one equipped with a power source, applications of them to environmental sensing device, and transportation equipments of small objects on water surface, are possible. Since it has been reported that the self-motion on water surface in possible by using an ionic liquid [BMIM][PF_6] (1-butyl-3-methylimidazolium hexafluorophosphate) an a fuel which causes surface tension gradient on water surface and generate propulsion force, we focused on self-motion using ionic liquids. To establish method to control driving force, driving time and moving direction of this micro self-motion mechanism powered by ionic liquids. We measured driving force of a locomotion which has a nozzle to report ionic liquid on water surface and evaluated effects of the shape of the nozzle.

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Recentlt, self-motion is attracting attentions as a new motion mechanism that does not require energy supply from outside. Micro self-motion mechanism, in expected to be applied to transportations of small bodies in the water and environmental sensing devices. Among them, driving method using surface tension gradient on water surface are known. By using ionic liquids with ampliphilic chemical structure which can modify surface tention of water surface, the object can be driven by converting chemical energy into mechanical energy directly. We already, confirmed that small objects depositing an imidazolium-based ionic liquid [bmim][PF_6] (1-butyl-3-methylimidaz-olium hexafluorophosphate) moved spontaneously on water surface. In this study, by using a magnetic ionic liquid [bmim][FeCl_4](1-buthyl-3-methylimidazoium Tetrachloroferrate) containing a magnetic anion, we examined a potential application to control the direction of the self-motion by applying magnetic field.

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Alternative Current Electroosmosis(ACEO) is suitable for micro actuation systems, because the ACEO flow can be stably generated without electrolysis with simple structure having no moving parts and is caused by electrostatic force which is effective in micro area. For that reasons, ACEO is widely used in analytical devices for fluid and particle manipulation. However, existing ACEO micropumps can only realize low pressure and low flow rate, which becomes obstacles for further application such as microhydraulics. This paper presents new design of ACEO micropump using Plate-Cylinder electrodes called PC-ACEO-MP(Plate-Cylinder electrodes ACEO micropump) to enhance its performance. Using FEM simulation, we indicate its possibility of realizing high pressure(>10kPa) and high flow rate(>1mm^3/s) with less than 1cm^3 effective pump volume by using electrode plate having many hundreds of thousands of holes(smaller than 1cm^3 in diameter). We also propose a novel MEMS fabrication process for the PC-ACEO-MP electrode and realize it as a large model with 36100 holes of 10μm in diameter).

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A surface acoustic wave (SAW) motor is small and low in profile with high speed and large thrust in linear motion. Hence the performance has been evaluated from transient response even though the reliability is rather low. We tried to measure the thrust directly using loading mass. Difficulty of thrust evaluation by loading mass is tiny size of the slider in mm dimensions and huge thrust in several N. Moreover, the moving distance of the SAW motor is short in a few cm. Hence the SAW motor has to be stopped before the mechanical system for the measurement becoming in static condition. The loading mass was connected with steel wires even though the wires were elastic. But we cannot use bulky material for mass connection due to small size. By evaluating the stretch of the steel wire, the speed vs. load was successfully measured. The loading force was estimated from the wire elasticity and the stretching value from the measurement using two sets of laser Doppler velocimeter (LDV). We successfully proved that the actual SAW motor thrust is 60 % larger than that of the estimated value from transient response; 4.0 N against 2.5 N for example.

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This paper presents a drive method with pulse currents of a transverse-flux motor having small cogging torques suppressed by short circuits of permanent-magnet fluxes for reducing the torque ripples. This paper also describes numerical analysis results of the flux linkage and torque characteristics for the rotor position for each drive method. The results indicate the drive method with pulse currents can generate larger torques and lower torque ripples compared with that with the same-amplitude sinusoidal currents.

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The demand for ultra precise positioning of nanometer-order is increasing with the progress of nanotechnology in semiconductor industry.Previously we developed the one axis stage driven by pneumatic bellows for such a demand, and realized ultra precise positioning and long stroke.However, not only a one axis stage, but also a stage with multiple degrees of freedom is often demanded in semiconductor industry. Previously, we proposed to unitize a pneumatic bellows and an elastic hinge guide and developed 3 degree-of-freedom fine motion stage using proposed actuator units of three. In this paper, positioning characteistics of this stage are examined. As a result, positioning accuracy was 50[nm] or less at both settling and tracking control. It is confirmed that the fine motion stage driven by pneumatic belows has gooog positioning accuracy.

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Comparative study of Kansei Engineering and Emotional Engineering is described and how they are different among Japan, Europe and US are discussed.

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We investigated the influence of the expectation discrepancy in weight perception that is affected by material recognition on product perceived quality. We construct the hypothetic model that explains the correlation between material recognition, product mass, expectation discrepancy, and perceived quality. To verify the model, We conducted a sensory experiment with 12 student participants using samples made of aluminum and ABS in the shape of a smart phone. From the result, we found that the product mass where perceived weight was heavier than anticipated differs depending on materials. The mass in aluminum sample is heavier than that of in ABS samples. We also found that when perceived weight is heavier than anticipated, participants' evaluation value on perceived quality is higher than when anticipated weight is heavier than anticipated. This result suggests that optimal product weight for good perceived quality is different in weight predicted by material recognition. Thus, designers need to carefully select the combinations of materials and weight to achieve high perceived quality products.

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Human perception of color depends on environmental factors such as background color and outside light, as well as object's color. To design color perception in consideration of such environmental influences, we developed a design support system that suggests optimum and robust solutions based on visual perceptual characteristics. We embedded CIECAM02 as a function in the system to translate between physical and perceptual parameters. The system visualizes Pareto solutions for multiple objective functions regarding color perception. We demonstrate that the system suggests an optimum strategy to search design solutions based on Pareto solutions mapped to the physical parameter space.

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In this paper, in the aim of applying Value Growth Design to artifacts design, we investigate artifacts which show a growth in value, and employ cluster analysis to extract the features of Value Growth Design. Value Growth Design enables an object to increase its value over time, and is based on a new design paradigm, Timeaxis Design. The case study reveals a total of 6 patterns throughout an object's lifetime, and the relationship between the elements of each pattern is investigated. This produces the main factors of value growth, which is contributory to the design of value growing artifacts. The application of Value Growth Design to artifacts design can enable the long-term usage of artifacts, and can also become a possible solution to multifaceted issues such as environmental problems and the demand for spiritual richness.

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A consumer's emotional response to a product is influenced by cognitive processes associated with the consumer experience, such as memories associated with the use of a product. We propose a cognitive neural model of user experience, the PEAM (Prediction - Experience - Appraisal - Memory) model, as a tool to aid in product design. We examined the spatiotemporal changes in brain activity associated with product evaluation and memory, using electroencephalograms (EEGs). The EEGs (25 electrode sites of the extended 10-20 system) of 10 healthy participants were recorded while the participants viewed images of products (e.g., bicycle, watch, and chair) followed by a preference rating, and while performing a recognition memory task for products. Our result showed that significant increases in gamma activity in the temporal areas during evaluating predict subsequent recognition. The finding suggest that the activity in temporal area is a predictor for recognition memory of products.

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In this paper, we describe the measurement of brain activity response during lathe operation in a VR environment by near-infrared spectroscopy (NIRS). Our experiments were performed in alternating segments of operating the lathe operation with sounds of processing and operating the lathe operation without sounds of processing. The results show in the case of the trials with sounds of processing, oxyHb tended to increase in the auditory area during lathe operation. On the other hand, in the trials without sounds of processing, oxyHb didn't change in the auditory area. The results also show that oxyHb tended to increase in the frontal lobe during the trials with sounds of processing and the trials without sounds of processing. This revealed that the brain was activated by the sound of processing during the lathe operation.

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There is a frequency locality in the auditory cortex. The aims of this study are reconstructing audio signal from fMRI (functional Magnetic Resonance Imaging) data measured primary auditory cortex of human. In order to develop a sound decoding system from brain activity, it is necessary to distinguish brain activities which respond to several frequencies of stimuli. Therefore the first stage of this study is attempted to establish a technology to decode a musical scale using fMRI. In this paper, it is shown by t-test that the brain activities have significant differences which respond to semitone-difference stimuli with 3-mm spatial resolution of fMRI imaging data. Thus, at around 2kHz, a prospect that decoding musical scale from brain activity data is possible on the frequency resolution of a semitone is obtained.

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By using haptic interfaces, a great deal of brush stroke learning methods have been studied, but many of them used visual information together with the tactile information where the tactile information is considered to be much inferior to the visual one. Therefore, the effects cannot be clarified in detail, and the way of utilizing the tactile devices were not enough established. In this study, we examine an instruction method of brush strokes to establish a way of utilizing the tactile devices. Focusing attention on the difference between the horizontal and vertical motion modes in brush strokes, we employed a hybrid position/force-based kinematic motion instruction scheme. A traction force was fed back to a learner in the following manner: the horizontal component was given to reduce the horizontal position deviation of a leaner from an expert, and the vertical component was given as a reaction force that were exerted by the expert. To confirm the effectiveness, a bush stroke experiment was conducted for a brahmi letter.

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In a measurement, measurement is influenced by uncertainties, part of which is contributed by the measurement instrument itself. We develop a new calibration method for laser velocimetry mainly for application in flow measurements. With the new calibration method, the measurement uncertainty can be quantified and it is also reduced compared to some former methods. In the former methods, calibration uncertainty was dominated by that of the calibration orbit radius, which is not accessible directly. Our new method solves this issue by utilizing a linear relationship between measurement outputs to the rotating radii of a calibration disk. We have used multiple pinholes to realize the calibration and confirmed its performance. In the present study, we propose a new realization of the calibration method using multiple points along a slit instead of multiple pinholes. We report the initial result of the performance evaluation based on the slip method. The functionality of the new realization was confirmed and the performance was investigated through an experiment. The performance is expected to be improved furthermore.

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Although the optical three-axis tactile sensor has unique characteristics capable of detecting three-axis components of applied force to each sensing element of the tactile sensor, it has inevitable defects such as blind spots between sensing elements and unstable contact status on the sensor-tip. In order to overcome these defects, the authors developed a tactile sensor based on human skin structure in the previous studies. However, the tactile sensor has still even a new defect, which decreases its sensitivity by means of the skin rubber. In this paper, we introduce a new fingerprint structure to increase its sensitivity. In order to obtain the best structure of fingerprint, we perform a series of FEM analysis and experiments using the fingerprint structure. As the results of numerical simulations and actual experiments, we found the best structure, in which skin-rubber thickness is 2.5 mm and fingerprint-ridge and sensing element align in-phase.

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Tactile illusions enable us to feel a real sensation of virtual objects by deceiving the human's brain. One of the illusions useful to operate in tactile display is velvet hand illusion (VHI). VHI causes a virtual texture sensation highly similar to the texture of a real object. The VHI facilitates to create virtually velvetiness or slippery texture sensation when a person rubs gently his/her hand both side of grid wires. In this paper, we describe the mechanism of VHI deduced by a series of paired comparison: the results showed the strongest VHI intensity occurred when the wire stroke r was almost equal to the wire distance D (r/D ≈ 1). Based on this mechanism, a pin-matrix-typed tactile display can be used as a VHI generator. In evaluation experiments, we compare the strength of VHI feeling generated by the pin-matrix-typed tactile display with the VHI feeling generated by the mesh wire and real feeling of velvet cloth using magnitude estimation. The VHI feeling generated by the pin-matrix-typed tactile display is almost same as that generated by the mesh wire.

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In this study, we have investigated the enhancement phenomenon of haptic perception caused by simultaneous tactile stimuli to both hands. In our previous studies, we have examined the contact conditions and how to move hand. This paper investigates spatial-temporal consistency of the stimuli in both hands. We gave spatial changes or temporal changes in tactile stimulation, and compared changes of the intensity of perceived stimulus. The result shows the influence of temporal changes is small, but the influence of spatial changes is large and spatial consistency of the stimuli is important for the enhancement effect.

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Psychophysics is an effective approach to measure events occurred in human mind, which is not observed from the outside. Since concentration is required to obtain reliable data from psychophysical experiments, volunteers participating in the experiments get tired. In order to obtain reliable data, we should estimate fatigue of the volunteers during psychophysical experiments. In this paper, we estimate the fatigue from variation in alpha-wave component obtained from a portable EEG (Mind tune, Toshiba). In the psychophysical experiments, volunteers perform to detect direction of edges, which are generated by a pin-matrix type tactile display. During the experiments, although the level of alpha-wave component decreased with increase of tasks, the level is recovered after a break. Therefore there is a possibility to measure the fatigue from level of alpha-wave component.

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Ground-penetrating-radars (GPRs) are used to survey underground f buried objects. In cases of multiple objects are buried at a nearby site in different depths, secondary reflections caused by the upper object are deteriorate B-scope images, and sometimes make us difficult to recognize the lower object occluded from the upper object: the secondary reflections are created from a process in which a pulse wave is emitted from a transmitter, travels via the upper object, the ground surface, upper object again, and arrives at a receiver. In this paper, the authors proposed a method of removing the secondary reflection. The method comprised of two stages: (1) modellings of the secondary reflection, (2) removal of a model-synthesized secondary reflection images from the raw B-scope images. Three kinds of models were introduced: the first model was representing the secondary reflection path length, the second, an intensity attenuation, and the third, a wavelength expansion. The effectiveness of the proposed method was confirmed through a laboratory experiment: two pipes were are buried at a nearby site in different depths, and the secondary reflection from an upper pipe interfered with the first reflection from the occluded lower pipe.

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Continuous monitoring of respiratory activity is a key technology for early diagnosis of sleep disorder diseases and other diseases such as asthma. Coherence of respiratory regularity is a significant indicator for mental stress assessment and physical fitness evaluation. A PVDF film is one of suitable material for wearable respiratory sound sensor because it is flexible and sensitive to low frequency sound. Furthermore, a curved structure of PVDF film was reported to have higher sensitivity. We have investigated sensitivities of the curved structure of PVDF film by FEM analysis, and also compared experimental results with the analysis results. Our previous research showed that the curvature of 9 deg. with doubly fixed clamped condition had higher sensitivity than other conditions in the experiments. However, it was also suggested that the clamping conditions in the experiments were not ideal and thus the sensitivity improvement was not obtained so much as those by simulation. In this research, we introduced a new boundary condition model considering clamping state in experiments to simulate sensitivities of PVDF sensors of multi-curved structure, and also fabricated wearable respiratory sound sensors of multi-curved structure. Simulation and experimental results showed that sensors of multi-curved structure have higher sensitivity than flat sensor.

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In this study, a body motion compensation method for blood pressure measurement using a pulse wave velocity (PWV) method is proposed. PWV method has advantages to provide continuous systolic blood pressure from pulse transit time (PTT), and to avoid an excessive burden caused by cuff used in conventional sphygmomanometers. However, the measurement accuracy of PTT is heavily reduced by body motion. In order to solve this problem, a body motion compensation filter is needed. To design the motion compensation filter, we made experiments using a motion simulator for grasping the relationship between body motion and its influence on pulse wave (body motion component). As a result, it became clear that body motion component is proportional to body motion acceleration, but its proportionality coefficients are different among subjects. It also became clear that the frequency of body motion component is equal to the frequency of body motion acceleration. Based on these results, we propose a body motion compensation filter, which could cancel the body motion components being estimated from the above-mentioned experiment. By applying this filter to the data of motion simulator experiments, the variance of PTT was decreased to 50%. In addition, by applying to the data of walking experiments, the variance of PTT was decreased to 65%.

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We measured the triaxial forces applied to the grasped object during the staple operation of a surgical stapler by a MEMS (Micro Electro Mechanical System) triaxial tactile sensor (Touchence Inc., FSI-020119P) to develop the criteria for the accurate automated suturing by surgical staplers. The compression force was 43.0 ± 0.1 N at the 5 mm from the tip of the stapler. This value was agreed with the value measured by a pressure sensor (KYOWA, PS-10KC). Moreover, 9.3 ± 0.3 N shear force was measured toward the stapler tip. The shear force of the orthogonal direction to the axis of the stapler was approximately 0 N. These result agreed with the prediction based on the movement of the stapler tip that the anvil jaw pushes the grasped object out. Thus, the triaxial forces applied to the grasped object during the staple operation can be acquired in real time by the MEMS triaxial tactile sensor.

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This study aims to develop a novel measurement system for the finger joint angle by using a soft polymer sensor, which enables easier evaluation of human motion. In the rehabilitation, it is important to evaluate human motion quantitatively for effective treatment. In this study, we focus on hand grip motion, which is important motion for eating and drinking. From the previous studies, it has been elucidated that the outputs from the soft polymer sensor are proportional to the mean of sensor curvatures. The sensor has good flexibility. Therefore, finger bending motion can be measured by attaching the sensor on the finger joint. To obtain the relationship between sensor outputs and finger joint angles, the sensor outputs during grasping motion is compared with the finger joint angles measured by VICON which is the 3D motion capture system. From the results, it is proved that this system is useful to measure the finger joint angle.

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The motion analysis method of the non-parabolic jumping motion using wearable sensor is proposed. The wireless inertial measurement sensor unit version2 (WIMU2) uniquely developed consists of 3D accelerometer, 3D gyroscope, 3D geomagnetic sensor, 9 AD channels, memory and wireless communication module. Twelve WIMU2 are mounted on upper body and lower one. The posture of the body is estimated using the axis direction of sensor that is modified by extended Kalman filter. When the hand or foot touches the wall or ground, touching position is considered as the origination of calculation, and 3D posture of whole body is constructed. The trajectory of the body during jumping is calculated by the double integration of measured acceleration from the trunk. To confirm the efficacy of proposed motion analysis method, one subject pushes the wall forward during jumping and lands backward. The experimental result shows that the proposed motion analysis method is able to estimate the posture and trajectory of the whole body during non-parabolic jumping motion.

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It is an important issue to prevent and cure knee osteoarthritis. Gait pattern is suggested to be related with the knee osteoarthritis progression. Therefore our objective is to analyze an elevation angle of knee osteoarthritis patient gait and to clarify the feature of movement by using approximate plane of elevation angle. As a result, the same planar law could be applied to a knee osteoarthritis patients gait as a healthy people gait. Some patients have the different approximate plane slope from that of healthy people.

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A purpose of this study is to develop motion assistive device for an upper limb. Motion assistive device should be controlled based on the model holding the characteristics of musculoskeletal individual to assist in safely. In this paper, measured the EMG signal and the angular velocity when were the wrist palmar flexion, dorsiflexion and the elbow flexion, extension. It was proposed a method based on the input EMG and output wrist, elbow angle to derive a MIMO-NARX model, estimates the wrist, elbow angle. MIMO-NARX model can represent a multi-input multi-output system nonlinear, and retain the characteristics of each muscle. Using the identified MIMO-NARX model, it was confirmed that it is possible to estimate the wrist, elbow angle with high accuracy, and coefficient of the MIMO-NARX model correspond to the size of the muscle mass. Fit rate of wrist angle was 99.72%, elbow angle was the 99.52%. Value applied to the flexor carpi ulnaris muscle was -15 to 10, extensor carpi radialis longus muscle was -10 to 2, biceps brachii muscle was -50-200. From this, it was considered that it is possible to evaluation of muscle mass to have of individuals from the coefficient of MIMO-NARX model.

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Recently, because the people who need help have increased by aging, the burden of care and nursing has been increasing. In this study, in order to prevent low back pain of nurses, we focus on the disproportionate burden on the waist. We have developed a portable posture improvement system for nursing scene, which enlighten "nursing behavior of small burden on the waist by utilizing body mechanics". The function of the system is realized by the warning in real time, such that users of the system take a poor posture with the disproportionate burden on the waist. In addition, we have aimed to generate the high motivation to prevent the back pain themselves, by mounting a function to display the rate of poor posture. This system can carry on day-to-day operations of nursing, because it is small and lightweight. We consider that this system is useful to prevent back pain of nurse while at work.

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In this study, we have been developing an active training wheel for the acquisition of the bicycle riding. This wheel is designed to support to recovery the slant angle not to fall down as if a parent correct the slant angle from backside when it is necessary in the practice. The rolling angle of these wheels are movable, so usually the wheels are set to the high position not to land and disturb the practice, and the wheel moves to land if the falling down risk is anticipated. After the development of our first model, we inserted an air spring between the joint and the wheel. This spring enables soft landing and quick recovery to the neutral position. The repulsion force, however, must be controlled not to roll over. In this study, we first modify the training wheel mechanism. After this renewal, the training wheel moved very smoothly. Next, we investigated a control algorism to control the repulsion force. After the basic response experiments, we decided to control the wheel by the angular velocity of the 5 degree when the bike is going to fall down. We also planned and made a robot riding simulator because this type of active training wheel has a possibility of the rolling over accidents. We have to examine the safety of this training system by using robot simulator before using real riding practice.

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This Paper presents a novel evaluation method for surgical robotics operation by analyzing user's brain activity. In this paper, the objective is to validate that the intraparietal sulcus which is the brain area activated significantly according to the change of the intuitive operability. In experiment, we measured the user's brain activity on the intraparietal sulcus by f-NIRS as the user controlled the virtual arm. The experiment was carried out with a variety of the kinematic position of virtual arm. As a result, the oxygenated hemoglobin activated significantly when the kinematics between master and slave is correspondent. We conclude that the oxygenated hemoglobin changed as the user perceives that the virtual arm belongs to the user's body.

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