In this paper, we investigated characteristics of Ti-Ni-Cu thin film metallic glasses (TFMGs)/ shape memory alloys (SMAs) for MEMS application with three dimensional structure. The Ti-poor Ti-Ni-Cu amorphous thin films (Ti content of less than 50 at.% and Cu content of more than 6 at.%) exhibited glass transition during crystallization proces and were TFMGs. Moreover, a little Ti-rich Ti-Ni-Cu (Ti-content of less than 51 at.%) samples also showed the glass transition. On the other hands when Ti content was more than 51 at.%, these samples didn't show the glass transition, irrespective of Cu content. Therefore, it is considered that the glass forming ability of Ti-Ni-Cu TFMG was better than that of the Ti-Ni-Zr TFMGs. The Ti-Ni-Cu TFMGs after crystallization at 973 K for 3.6ks showed the single martensitic transformation of B2-B19 phase upon cooling and heating. When Ti content was around 50 at.%, peak temperatures of martensitic transformation O* and A* increased with increasing Cu content until 16 at.%. Further Cu content increasing, O* and A* decreased.

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Magnetostrictive materials often used for several sensors and actuators from some features that are fast response, high power, and contactless actuation. Magnetostriction and relative permeability are important characteristics to determine the performance of the sensors and actuator, however, it need the different sample to evaluate magnetostriction and relative permeability. So that, it takes a lot of time to search new magnetostrictive materials or optimize composition of alloy magnetostrictive materials. The combinatorial method could search novel alloy materials or optimize composition efficiently compared to the conventional material searching method. In this research, we proposd the MEMS device for the combinatorial materials searching method. This device could evaluate characteristics of magnetostrictive material that are magnetostriction and relative permeability. Moreover, magnetostriction an drelative permeability are evaluated by the change of capacitance, induced electromotive force, respectively. In this paper, we show the fabrication process and fabricated device that keeps the cantilever structure.

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MEMS cantilevers with multi-layer structure of sputtered Fe_<60>Pd_<40> film (2μm) /SiO_2 (0.8μm) / Si (50μm) were fabricated and characterized. MEMS cantilevers with a length of 1-8mm were used to evaluate influence of different initial deflection due to film stress on deflection measurement under magnetic flux. It was found that initial deflection, corresponding to cantilever length, was little influenced on magnetostriction measurement results. Effect of annealing on magnetostriction of the Fe_<60>Pd_<40> film was also evaluated using 8 mm long MEMS cantilevers. Magnetostrictive effect increased to 1.5-2 times after annealing at 350〜450℃ for 30 min, In contrast, magnetostrictive effect was lost when annealing was carried out at a temperature of 500℃ or higher.

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MCF haptic rubber (MCFHR) contains the rubber and the magnetic compound fluid (MCF) which has developed by Shimada as a magnetic reactive intelligent fluid by compounding μm-ordered metal particles and magnetic fluid (MF) having magnetic paticles (Fe_3O_). The characteristics of the MCFHR previously made of by utilizing a natural rubber and by the application of a magnetic field have been changed due to aging. In the present study, a new making method of preventing the aged deterioration is shown. By the application of the DC voltage as well as by that of the magnetic field, the electric current path is formed by many double bonds of the natural rubber arranged as the radical polymerization along the line of the magnetic force direction by the effect of the magnetic clusters of metal and Fe_3O_4 particles.

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Electrode catalyst used in industrial electrolysis is important material which affects oxidation-reduction reaction materially. The electrode catalyst having high catalystic activity and high durability gives efficient production of chemical materials. In this study, we proposed to search for new electrode catalyst using a combinatorial method. The evaluation substrate consisting of 72 catalyst samples and 9 Pt reference electrodes was designed and fabricated by a micro electro mechanical system (MEMS) technique. The thin film electrode catalyst library on the evaluation substrate was prepared by a combinatorial multi target sputtering system using 3 pure metal targets (Ir, Ru and Ti). The alloy compositions of these thin films were measured by an energy dispersive X-ray spectroscopy. To evaluation the characteristics of catalyst samples, the polarization curves (current density/potential curves) of catalyst samples were measured by the potential sweep method. Surface poisoning and elution of catalysis samples were observed by an optical microscopy. Finally, we confirmed that the proposed combinatorial method was useful to search for new electrode catalyst materials.

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Ionic liquid (IL) is a kind of molten salt, which has negligible vapor pressure. Therefore IL can be utilized as a support for soft materials for observation under vacuum by electron microscopy. However, it has been concerned that IL may harden by electron irradiation during the electron microscopy observation. The purpose of this study is to reveal the relations between process of IL hardening, irradiation conditions of electron beam (acceleration voltage, irradiation density) and parameter of IL such as volume of IL. Adhesion force generally has strong correlation with surface tension, which is proportional to the adhesion force. To estimate the degree of hardening, adhesion force of an individual droplet of IL was measured in scanning electron microscope (SEM) equipped with nanomanipulator. Experimental data show that the adhesion force increases for several tens minutes, and then rapidly decreases. Correlating this result with SEM images taken simultaneously, we constructed a model. At the process of a model, Surface region of IL droplet hardens rapidly and forms solid film due to high energy electron irradiation. Film gradually increases its thickness by hardening of IL near the solid/liquid interface. Simutaeously, liquid phase of IL at inner region of the droplet also hardened slowly due to electrons penetrating to inside of droplet.

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This paper reports etching characteristics on the Si{100} and {110} wet etching in 0.25 and 1 wt%TMAH solution. Variations in Si{100} and {110} etching rate in the solution were large. As its feature, etching rate was dividend into a higher rate part and a lower rate part. The etching rate increased gradually with increasing temperature below 80degC. The etching rate at 88degC was lower than that of 80degC. Larger size of pyramidal hillocks was appeared at higher part of the etching rate. Smaller hillocks were observed on the surface of the lower etching rate.

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Thermal-photovoltaic hybrid solar generators is one candidate for energy harvesting devices. Near-infrared solar light which cannot be used for photovoltaic generator is used for thermoelectric generator. Hybrid generator with buls lens to generate temeperature gradient has been fabricated. However, it is difficult to reduce the volume of the generators due to the bulk lens. In our study, we proposed a thin-film thermoelectric generator with anti-reflection structures on the hot side of pn junctions. First, we designed the anti-reflection structures using rigorous coupled wave analysis. When the grating period was 200 nm, the reflectance exhibits minimal value of 6.7%. Anti-reflection structures was fabricated using self-assembled silica microspheres and following CuO thin film deposition. The silica microspheres were assembled by dip coating. Then, the CuO thin film were coated by reactive sputtering on the self-assembled microspheres to reduce the energy loss and to convert the solar light to thermal energy. Finally, we investigated the effect of the ant-reflection structures using a commercially-available bulk thermoelectric module. The generation voltage of the modules with anti-reflection structures was increased by comparing to the modules without the structures. This result indicates that the near-infrared solar light was efficiently absorbed and converted to the thermal energy by anti-reflection structures.

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A new fabrication method of minute metal structures, which have optical properties of surface, on a quartz glass sustrate is reported in this paper. Minute metal structures are useful to develop metamaterials, which have artificial optical properties that have not existed in nature. The proposed fabrication method is a combination of Nano Plastic Forming (NPF) and self-organization technique by annealing. Firstly, gold thin film is deposited on a quartz glass substrate by DC spatter coater. Secondly, rectangle groove pattern is fabricated by NPF. Then, the substrate is annealed in an electric furnace to induce self-organization of he gold. Finally, SiO_2 spacer layer and gold thin film are deposited on this structure. In addition, optical extinction spectra are measured in the wavelength of visible light and near-infrared region. This structure shows high absorption peak at the wavelength of 966 nm. This absorption mechanism is discussed from the view point of electric circuit.

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Metal nano-dot array, consisting of a glass substrate and metal dots arranged on it, has the property of localized surface plasmon resonance and it's expected to be applied to optical devices or biosensors. For fabrication of such minute structures EBL and FIB are not always suitable due to their high facility cost, low throughput and stringency of processes. In order to fabricate nano-dot array more simply and efficiently, the authors propose its fabrication metod utilizing ultra precision machining. 1 μm-pitch line & space groove pattern and lattice groove pattern are made on a soda glass and quartz glass substrates by ultra precision machining with diamond tool. After gold coating on the substrates and annealing them, gold nano-dots aggregate and their alignments are controlled by the groove pattern.

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In this study. we suggested simple and easy fabrication technique of flowe-like nanomaterials called Nano Flower (NF) by stress-induced method. From the observation of NFs grown on substrates which have different surface conditions, growth of NFs is probably related to residual stress of surface of substrates. EDS analysis results show that NFs grow up by taking in atmospheric carbon dioxide. NFs are expected as application to carbon dioxide capture and storage.

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Metallic ion concentration on Ni-W planting bath had little influence on the thickness of Ni-W films. On the other hand, concentration increasing of metallic ion decreased the content rate of W in Ni-W film and suppressing nodules on Ni-W film. Ni-W plating bath with a metallic ion concentration of 0.75 M was largely similar to that of 1.0 M in content rate of W in Ni-W film and surface shape of Ni-W film. Since the content rate of W in Ni-W film and suppression of nodules are in the relationship of trade-off, it is necessary to search a metallic ion concentration that achieves high content rate of W and suppression of nodules at the same time

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A sharp tip-separable microneedle device for trans-dermal drug delivery systems (DDSs) is developed by MEMS technologies. At first, a Si microneedle was fabricated by applying a photolithography and anistropic wet etching of KOH. Then, a tip-separable microneedle device was produced by the molding process. A sharp tip-separable microneedle device is composed of a sharp tip containing medicine and a supporting base. It has a hook structure between them to separate the tip after its penetration into the skin. Thanks to the hook, the tips penetrated into the skin surface are easily separated and placed in the skin inside by removing the supporting base. It has an advantage that medicine injection time drastically decreases by separating the tip into the skin inside. We evaluated the penetration performanceof eight-sided and rounded knife-edge Si pyramids, as a shape of the tip structure. We inserted them into an artificial skin of a silicone rubber sheet and confirmed that the eight-sided Si pyramid had a larger displacement than the rounded knife-edge one at the same applied load. Thus, we used the eight-sided pyramid shape for a sharp tip-separable microneedle device. Thanks to the sharpness of the Si microneedles, sharp biodegradable tips with the radius of 500 nm could be fabricated.

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Biomolecules monitoring methods has been studied for the management of diseases like diabetes or hyperlipidemia for several decades. In this study, we report on a novel high sensitive electrochemical therml micro sensor based on VO_2 for an enzymatic healthcare monitoring system. In the process of glucose oxidation with the catalysis of enzyme, heat will be generated, which can be measured by a high sensitive thermal micro sensor so that the concentration of glucose solution can be calculated. A VO_2 thin film is used as a material of thermal micro sensor due to its high temperature coefficient of resistance of 15000 ppm/℃. The VO_2 thermal micro sensor is fabricated by the technology of MEMS with high temperature resolution of 0.299 mV/√Hz. This sensor has been utilized for the estimation of glucose concentration as an example. The result of glucose estimation indicates that the time rate of the output signal has positive correlation with glucose solution concentraitons.

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Lubricating oil is widely used to improve performance and life of various machines. However, when amount of moisture in lubricating oil increase, lubrication performance of the lubricating oil deteriorate. It cause the trouble of the machine. Therefore, the sensor to monitor amount of moisture in lubricating oil is need. This research propose capacitance type moisture sensor that can measure the relative humidity of lubricating oil in the real time. Dielectric constant changes by moisture absorption of the dielectric of the sensor. Relative humidity can be monitored by detecting changes of capacitance. So, it is need that electrode of capacior has porous structure to facilitate moisture absorption of dielectric. In the paper, this electrode was deposited by oblique angle sputtering in high sputtering gas pressure. We defined incidence angle of sputtering particle. And we fabricated three kinds of sensors whose incidence angles of sputtering particle were respectively 90, 60, 30 degrees. Those sensors were evaluated for the relative humidity in the atmosphere using temperature and humidity testing chamber. As incidence angle decreased, hysteresis decreased. (90 deg.:12.2%F.S., 60 deg.:10.1%F.S., 30 deg.:7.2%F.S.) We considered the reason of this decrease of the hysteresis is that porosity of the electrode increased because shadow effect became remarkable.

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We established a simple fabrication process of patterning vertically-aligned carbon nanotubes (CNTs) on reaction field for bio sensor and controlled clumping CNTs to extend effective surface. The process mainly consists from transferring CNTs to patterned resin. The resin was used Polydimethylsiloxane (PDMS) which is patterned by using the mold. The patterns are adopted hexagonal closet packing. Pitch ware prepared three patterns but other pattern's parameteres are same condition. As experiments, the CNTs synthesized on Si substrate by chemical vapor deposition (CVD) method. Synthesized substrates were set on pattened resin and loaded. Transferred CNTs were clumped by fluorescence particles suspension and ethanol. SEM images showed that the vertically CNTs are successfully transferred to the patterend PDMS after the synthesis substrate was peeled off and that configuration of top of clumping CNTs were opened to outside. We defined the transfer rate to verify the efficacy of propose process and evaluated. In each of the patterns, transfer rates are very high. The propose process easily could transfer CNTs on PDMS in large area. We will evaluate this sturcture as biosensor in future.

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It is known fine bubbles with micro-or nano meter order diameters exhibit diameter-dependent unique characteristics, and some related applications has been developed. Development of further applications requires much detailed understanding of size effect on their fundamental properties. Here we propose an application of carbn nanotubes (CNTs) for a tool of generate and operate individual bubbles with selective size. Generally production of finebubbles for application use is conducted by top down approach such as mechanical sharing of large bubbles in liquid, so that the bubbles are obtained as a suspension with rather wide diameter distribution. In our study, individual CNTs work as a electrodes for water electrolysis, therefore the proposed device enable us to generate individual bubbles at CNT tip. If individual CNTs hold isolated bubbles at tip continuously, array of size-controlled bubbles can be realized applicable to various size-selective measurements. To realize such a device using vertically aligned CNTs, some technical problems should be solved such as aggression of neighboring CNTs by capillary action in water. Therefore, we fabricated CNT/resin composites as the electrode. Tips of individual CNTs are isolated on the surface of composite, so that they can work independently as the electrodes. Atomic Force Microscopy (AFM) revealed that numerous protrusions consisting if CNT tips existed on their surface and bubbles selectively generated at such protrusions by electrolysis with 5% sodium chloride solution. In situ AFM also showed time-dependent growth of nanobubbles in 10 seconds order to be certain size and, and gradual shrinking in 10 hours.

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We proposed a microvalve using photoprocessible thremoresponsible gel, which is called "Bioresist". Bioresist has characteristic of shrinking higher than 32 degree Celsius and swelling lower than 32 degrees. The volum change is utilized for opening and closing the microvalve. Since Bioresist is patterned, we can fabricate any arbitrary 2D shape of Bioresist using photolithography. We developed a microvalve which can control opening and closing by integrating the patterned Bioresist with a microheater using MEMS technology. The microvalve using Bioresist hasthe advantage of high speed response and low power consumption. We evaluated the relationship between applied current required for opening the microvalve and flow rate when microvalve were tested under regular pressurized flow with de-ionized (DI) water. As a result, flow rate is proportional relationship with applied current. It was shown controllability of flow rate by applied current.

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Magnetic resonance imaging (MRI) is the key technology to investigate anatomy and phyisiology by a non-destructive imaging method. The analysis of molecular structures in nano-scale plays an important role for future nanotechnology. Since the spatial resolution of conventional MRI sytsems is limited to tens of micrometers, the high sensitive magnetic sensor is required for imaging in nanometer spatial resolution. The luminescence of nitrogen vacancy (NV) centers in diamond is sensitive to magnetic field, which applicable to MRI at room temperature through optical detection. Si scanning probes with a diamond particle having the NV centers are developed. Firstly, the diamond particles with the NV centers is deposited on a dummy wafer by microwave plasma chemical vapor deposition (MPCVD) with additional N_2 gas. While a graphite component in the diamond particle is observed by Raman spectroscopy, and the luminescence of the NV centers has been slightly detected. After XeF_2 etching and annealing, diamond particles which own NV centers are picked up and fixed onto the fabricated probe pillar using a glass needle and glue.

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In this paper, an experimental investigation on the controllability of a colloidal damper, employing a water-based ferrofluid (FERROTEC MSGW10) working against a liquid-repellent nanoporous matrix (gamma alumina, silica gel), is presented. Control of the dynamic characteristics is obtained by moving permanent neodymium annular magnets, which are placed either on the piston head (axial magnetic field) or on the external surface of the cylinder (radial magnetic field). In order to properly select these magnets, flow visualizations inside of a transparent model damper were performed, and the quantity of displaced liquid by the magnet through the damper's filter and through the nanoporous matrix was determined. Also, experimental data concerning the variation of the magnetic flux density at the magnet surface versus the hight of the magnet was collected, and based on it, the magnet's optimal height was determined. Then, the 3D structural model of the trial colloidal damper, obtained by using Solidworks and the excitation test rig are presented. From excitation tests on a ball-screw shaker, one confirmed larger damping abilities of the proposed damper relative to the traditional colloidal damper, and also the possibility to adjust the damping coefficient.

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We investigated the effect of surface voltage on biomolecules diffusion in micro reaction field with micro-pillar array. Using particle image velocimetry, the visualization of fluorescent particles motion as biomolecules diffusion in the reaction field with different structural dimension of micro pillar was demonstrated. The surface voltage of reaction field was changed by different pH of suspension liquid containing fluorescent particles. For the investigation in the effect of surface voltage on the diagnosis property such as detection limit and reaction efficiency, the particle number distributed near the surface of micro pillar structure was measured from the visualization of fluorescet particles motion by MATLAB. The result shows that particle number increases with increasing surface voltage positively because of the weakness in the interaction between reaction field and fluorescent particle caused by electric double layer (EDL). Moreover, decreasing the structural pitch of micro pillar, the significant effect of surfce voltage was indicated.

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We invented noble device for bio analysis to reduce sample volume and detecting time. We focused on increasing surface area and circulation of ligands. Large surface area leads to increase immobilized receptor, and circulation of receptor promote reaction. To get large surface area, the device is consists of stacking micro structured film. Because micro structure film has a lot of pillar, surface area is a few times than of ordinary film and diffusion area of ligands is small. And to achieve circulation of ligands, the device is rotated with magnetic stirrer. This device can be used in ordinary micro plate well without special equipment. We used 3D simulation to determine design parameter. 3D simulation showed that micro structure influence flow pattern and bio analysis. To validate this results, we demonstrated bio analysis of rubella virus with the device. As a result, in positive sample, higher sensitivity was showed with the device than only micro plate well. In negative sample, high surface area device showed large absorbance. This result was consistent with simulation.

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Nanomechanical resonators are widely studied for the applications to various sensors and oscillato It is difficult to capacitively detect its vibration of nanomechanical resonators because of its small capacitance and large motional resistance. One of the methods for lowering the motional resistance is to use mechanically coupled resonators. In this method, the capacitive detection of the vibration will be available by increasing the total capacitance. In this research, the coupled multiple nanomechanical resonators are designed, fabricated and evaluated. The nanomechanical resonators have a shape of clamped-clamped beam structure and those can be vibrated at a flexural mode. Its length is 21.3 μm, width is 500 nm, thickness is 5 μm, and the capacitive gap is 300 nm. The resonant frequency of fundamental flexural mode is designed to be approximately 9.4MHz. The number of coupled naomechanical resonators are 100. The fabricated resonators are evaluated by network analyzer. As the result, some resonant peaks are observed, which shows that most of nanomechanical resonators will be synchronized.

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A micro gripper with high-stiffness was designed and fabricated for handling of thin bio-sheets. Flash-evaporated thick (30 μm) TiNiCu shape memory alloy (SMA) film was employed to obtain sufficently stiff gripper. Thin film circuits of Pt heaters and Pt-Au thermo couple were integrated on the SMA micro gripper. The integrated heaters were designed so that the gripper can be reversibly driven between holding and releasing position. The SMA micro-gripper was closed at room temperature because the inner and outer arms of the gripper were similarly deflected by intrinsic stress of the SMA thick film. The outer arm of the gripper was reversibly deformed to 100μm in the direction of gripper opening when it was heated above phase transformation temperature. Spring constant of the gripper inner arm was about 30 N/m corresponding to a gripping force of 3 mN when 100μm thick sheet is held by the gripper.

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Recently, the RF-MEMS (micro electro-mechanical systems) switch is required rapidly to be installed such as mobile information devices. Therefore, we have been investigating a bi-stable mechanical actuator in order to realize RF-switches. Our bi-stable actuator was three-terminal comb-drive actuators which has two comb-electrodes pull a moveable mass in each side and realize two static states. The distance between two stable states was 28 um. The potassium ion electret technique which has developed in our laboratory was utilized for low-voltage actuation. The electret potential was 135V. We reported previously that the minimum operation pulse voltage between two bi-stable positions was 13V (pulse width was 300 us). In this paper, we measured the switching voltage between two bi-stable positions with DC voltage (applied time was 10 s). As a result, the minimum operation step voltage was 4.5V.

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Recently the realization of the electrostatic speaker is expected with the popularization of smartphones. In this paper, the structure of the electrostatic MEMS speaker is suggested and the characteristic is measured. The electrostatic MEMS speaker has a comb-drive actuator which vibrate in a longitudinal direction. The speaker can be drive with zero bias by introducing the Potassium-ion electret into the comb-erectrodes. The design concept of this device is making of the MEMS speaker which realize a sound pressure level 70〜80 dB in a rsonance frequency at 2 V with the size of the vibration board which is equal to an earphone. The sound from the fabricated speaker was heard at applied voltage 30 V and charged voltage 250 V. when the relation between the vibration velocity and the frequency was measured by the laser Doppler vibrometer, the value roughly match up to the simulation. However, the problem is that various resonance mode come about and the drive voltage is higher than the design value. In the future, the resonance mode will be confirmed and low voltage driving will realized by reviewing the design.

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The purpose of this study is to investigate the shock attenuation properties of long pile synthetic turf by modeling and simulation. Three types of sepecimens which have different hardness were used for comparing the shock attenuation properties. The hardness was controlled by the composite ratio of infill material, i.e. normal type specimen was formed by the sand and the rubber chip with 1:1 volume ratio, 2:1 for hard and 1:2 for soft. To identify the model parameters, multi-intensity multi-area impact test which was constructed by ten grades of impact intensities and five kinds of test feet were performed to each specimen. Although the identification accuracies were not so high, the parameter sets for the each specimen calculated from the identification could represent the differences of the specimens and simulate the FR (Force Reduction) values as shock attenuation properties against the landing impact of running. In conclusions, FR values decreased with increasing the impact duration at the same impact area and also decreased with increasing impat area at the same impact duration.

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Hollow barrel baseball bats have higher batting performance than wooden bats. Generally, hollow metal bats are made from aluminum alloy tubes, and hollow composite baseball bats are madewith fiber glass, carbon yarn and others. In this study, a hollow composite baseball bat, which has a better batting performance than current commercial metal or composite bats, was proposed. The materials of the proposed composite bat include: an aluminum alloy in the grip part, coupled with an aluminum alloy and CFRP (Carbon Fiber Reinforced Plastics) in the barrel part. The effects of the bending and hoop modes of the hollow metal and composite barrel bats were investigated by modal analysis. Collisions between the bat and baseballs thrown using the pitch types of no-spin (knuckle ball) and back-spin (fastball), and the vertical offset distance (the height of the center distance between the bat and ball) varying between 0 to 20 mm were simulated. From the results of the simulations, the proposed new bat was found to have a high BBCOR (Bat-Ball Coefficient of Restitution) compared to metal baseball bats. It has been shown that the new composite barrel bat increases the performance of the hollow baseball bat.

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The purpose of this study was to quantify the contribution of the whole-body joint torques to the vertical component of the bat head velocity during baseball batting motion. The segments and bat were modeled as a system of sixteen-ridig linked segments, and constraint axes of the elbow, wrist, knee and ankle joints were modeled with anatomical constraint equations in order to consider the degree of freedom (DOF) of the joint. Each hand was considered to be connected with the bat through zero DOF joint. The equation of motion with respect to the whole-body and bat was obtained from 1) the equation of motion for each segment, 2) equations for constraint condition in which adjacent segments are connected by joint, 3) equations for constraint axes of joints. The dynamic contributions of the joint moments, shoulder joint force, motion dependent term and gravity term to the vertical component of the bat head velocity was derived from the dynamic equation of the system.

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Musculoskeletal simulation in running considering the tension property of compression wear was conducted in the present study. In elements constituting a compression wear, zonatoin cloths were reproduced as virtual ligaments on the musculoskeletal model. The tension curve of the cloths could be represented in the virtual ligament model. The reference points were placed on the leg of musculoskeletal model. The virtual ligaments were represented by connecting two reference points. If a virtual ligament was extended than the natural length, tension was generated in the compression direction in proportion to extension from natural length. As an example of analysis, a case of four zonation cloths on the legs was analyzed. An actual human running motion and tension property of the real cloths were put into the model. The target muscles of analysis were quadriceps and hamstrings. From the simulation results, the effects of the tension on the muscle force was confirmed by comparison between results with the wear and those without the wear.

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The purpose of this study was to quantify the functional roles of the swing leg joints during maximal velocity phase in sprint motion based on multi-body dynamics. Five male sprinters (height: 1.74±0.03m, body mass: 66.6±4.7kg, personal best time in the 100m: 10.9±0.27s) from a university track team performed 60m maximal sprints on a straight track in this experiment. Video data were recorded using three high-speed digital cameras (EXILIM-EX-F1, CASIO) operating at 300fps. Two dimensional kinematic and kinetic data of the participants sprinting around 50m were analyzed by using the trajectory of 25 landmarks of the body. In order to quantify the roles of primary joints such as hip and knee joints, which exert large joint torque, ankle joint input was treated as angular acceleration instead of joint torque. The results indicated that 1) this method enabled us to quantify the joint function of the swing leg in sprint, 2) the main generating factor of the swing leg motion was hip joint torque, and 3) ankle joint torque was necessary to control the orientation of the foot segment.

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A compact gait analysis using one wearable inertial sensors is discussed. Because gait analysis using combination of a 3D camera system and force plate is very expensive and time consuming, a very simple and cheap gait analysis for personal use is proposed. An inertial sensor is mounted on the trunk of the subject and the ground reaction force and energy dissipation are estimated by using triaxial acceleration defined in the global coordinate. At first, the triaxial ground reaction force is estimated by using the triaxial acceleration of the center of gravity and the equivalent mass of the subject. Triaxial velocity of the center of gravity is estimated by integrating acceleration and suppressing the integration error by the proposed compensation method. Next, the dissipation power is estimated by multiplying the ground reaction force and the velocity. Finally, walking experiment is carried out and the validity of the proposed method is confirmed.

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In this paper, we have presented a new direction for gait measurement without the use of a camera or video images. The change in the electric potential of the human body that is caused by the walking motion induces an electrostatic induction current in the electrode placed at a distanceof a few meters from the human body. Using this technology, we have developed an effective non-contact and non-attached technique for the detection of human walking motion by detecting the change in this human-generated body charge. This technique effectively explains the behavior of the waveform of the electrostatic induction current flowing through a given measurement electrode through a capacitance model of the human body. Gair waveforms of 8 healthy individuals aged between 22 and 24 years were obtained by the proposed technique. By data processing techniques such as differentiation and normalization after Fourier analysis of the obtained waveform, we obtained the Pearson correlation coefficients with each other. Results show that there is high correlation in spite of different walking tempo. This suggests that process of human walk has a self-sustaining and dynamic rhythm by the integrated signals from the spinal cord in spite of walking tempo.

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We have studied the walking posture diagnosis using inertial measurement units. We acquired the acceleration data of a waking model and a general subject attached inertial sensors to their ankles, creating the algorithm judging angels of the upper body and the leg opening from the analysis of the waking movement features.

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In this paper, two foot strike pattern, which are the rear foot strike (RFS) and the fore foot strike (FFS), are compared from the viewpoint ofthe joint moment, joint reaction force and muscle activity using the actual measurement of running for two subjects. As the results, the landing impact force has two peaks for RFS while one peak for FFS, and the significant features can be observed in the ankle joint rather than the knee and hip joint. The joint moment of the ankle joint for RFS acts toward the dorsal flexion direction at the beginning of landing, and then toward the plantar flexion direction, while the one for FFS acts toward the plantar flexion direction during landing. The bone-on-bone force for RFS shows two peaks as similar with the landing impact force. For RFS, the Tibialis anterior much works while for FFS, the Gastrocnemius and the Soleus works much. Moreover, the differences of subject A and B are shown as the contribition of joints on the running.

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It is important to investigate the effects on a seated human body exposed to whole-body vibration. We have shown the effects on a human body based on the changes in the seated postures exposed to vertical excitation. We, however, have not dealt with fore-and-aft or lateral excitation. Accordingly, the major objective of this study is to investigate the relationship between the vibration characteristics on a seated human body and the seated postures exposed to fore-and-aft, lateral and vertical excitations, respectively. Ten seated male subjects were measured at their heads in fore-and-aft, lateral, vertical, and roll and pitch directions, in terms of seat-to-head transmissibility and driving-point apparent mass, under random vibration excitations in the three directions. The random fore-and-aft and lateral excitations were in the range of 1-20 Hz, and the vertical excitation was in the range of 1-30 Hz. Each magnitude of the random excitations was 1.0 m/s^2 rms. Three different seated postures were examined: upright, relaxed, and the intermediate thereof. As a result, the resonance frequencies of 2-3 Hz and 10-2 Hz were obtained for for-and-aft excitation and lateral excitation, respectively. The results also showed that, under vertical excitation, the resonance points vary depending on the seated postures, while they do not under fore-and-aft lateral excitations. Moreover, the transmissibility of the pitch direction durng vertical and fore-and-aft excitation could be considered as being coupled vibration.

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In the modern society, many people feel loneliness and uneasiness, dissatisfaction memtally. These accumulations may produce serious social problems such as the suicide. "Iyashi" that is stimulation to restore a state of mind is effective to improve these problems. In this study, I focused on tactile stimulation and measured the brain activity of the "Iyashi" state using fMRI and alanyzed it. In fMRI experiments, "Iyashi" state was reproduced by tactile stimulations and storythinking. The areas activated in "Iyashi" state by tactile stimulation were anterior cingulate cortex and middle frontal gyrus. Anterior cingulate cortex was also activated by storythinking. It was shown that these areas was deeply related to "Iyashi". In addition, I inspected whether could distinguish "Iyasi" state by a brain activation pattern. In the case of only tactile stimulation data, it was succeeded to distinguish significantly. In the case of different input stimulation data, it was not succeeded. It was suggested that processes of "Iyashi" were different.

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Stresses are roughly classified into distress and eustress. However the method to reduce distress is to receive a counseling, more convenient stress evaluation system without counselor is needed. For this reason, a stress evaluation system using onomatopeias was developed without reducing user's distress. In this study, the improved stress evaluation system using onomatopeias was developed and evaluated. Twenty male subjects, with their ages from 21 to 25, were participated in the three-day experiment using both the previously developed system (system A) and the improved system (System B). After that, subjects answered a 5-grade system comparison test including 10 evaluation items. Afterward, subjects selected system A or system B, and used the selected system more for one week. One week later, subjects answered another system evaluationtest including 7 evaluation items. The results showed that "The more excellent system is system B than system A" was majority. However, in the usability evaluations system A was better than system B. That is, it is needed to improve more usability.

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We have measured the aerodynamic forces during the landing phase for a V-style as well as the free flight phase by employing a full size modelin a wind tunnel. A full size model of a ski jumper was mounted in 6.5m×5.5m low-speed wind tunnel at JAXA. In the case of the ground effect experiment, the ground plate was set over the whole test section. The height of the ground plage was varied in this series of experiments. It was found that the lift depends on the height difference between the ground plate and the tail of skies. The lift increases with decreasing the height difference when the angle of attack is positive. On the other hand, the lift decreases with decreasing the height difference when the angle of attack is positive.

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Recently we have enjoyed the sport "Ultimate" using flying disk in the world. We play Ultimate with seven people per team. The flying disk used in this competition isn't made in Japan. So, it is expected to develop the inexpensive and highly efficient flying disk of Ultimate. In this research, I understood the aerodynamic properties of flying disk by fluid forces measurement and Stereo-PIV measurement, CFD analysis. Also, I verified the appropriateness of CFD analysis by comparing fluid coefficients of experiment with that of CFD analysis.

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When preparing the manuscript, read and observe carefully this sample as well as the instruction manual for the manuscript of the Transaction of Japan Society of Mechanical Engineers. This sample was prepared using.

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The decrease in fluid resistance is one of the important keys for the purpose of shortening of the sports time record. By wearing of a low resistance swimsuit, it still reminds us that there were a lot of large time record shortening in swimming races of Beijing Olympic. The development of low resistance cloth as the application to sports is very important. This study is intended to suggest the best piece of cloth in specific speed area of sports. The fluid resistance concerning the change of cloth materials, surface roughness, surface processing method, seam position and the difference in sewing were investigated by one of the authors. In this time, Influence of slack of the clothes was also investigated. In addition, we performed the aerodynamics experiment of the sports wears which considered the seam position of the cloth as a result of cylinder model and obtained an interesting result. The obtained results showed that there were no influence on the seam position and cloth materials.

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Scuba diving is becoming popular as a leisure activity. Although manufacturers make various types of diving fin, these developments are based on qualitative methods because of the difficulty in estimating the fin effeciency quantitatively. In this research, a simulation model to assess the performance of diving fin was constructed by extending the swimming human simulation model SWUM. In this model, the fin was modeled as a series of five rigid plates. These plates were connected by virtual springs and dampers, and fin's elasticity was represented by springs. The swimming motion with fins was obtained by motion capture experiment, and the fin parameters such as the shape, the rigidity, and the hydrodynamic coefficent, were determined by comparing the deformation and the drag measurement with the result of simulation. Finally, the diving swimming was simulated, and the swimming speed was found to be about 0.85 m/s. The speed was 10% higher compared with the actual diver's speed.

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Low back pain of caregiver has serious problem in welfare field. Transfer motion is thought as a cause of the low back pain, and it is necessary to reduce the lumbar burden. Also practical quantification method of lumbar burden is required strongly. This study aims to develop a practical and dynamic evaluation method of lumber burden by measuring surface muscle potential of the Erector spine muscle. This study delas with transfer motion and divide it into three motions, "lifting motion", "rotation a motion" and "unloading motion". Experiments have been conducted to show that "lifting motion" and "rotation a motion" can be evaluated by the surface muscle potential of the erector spine muscle by previous studies. This paper focuses on the "unloading motion" and, the relationship between the load and the "surface muscle potential of the erector spine muscle" is confirmed by experiments. It is also shown that the lumbar burden during "unload motion" is possible to be evaluated by using the surface muscle potential. In addition, this study evaluates, whether dynamic evaluation by using the proposed evaluation method is possible. Because caregivers are required to slow down during the "unoad motion", inertial force increass the load during decelerated motion. For an example, a dynamic evaluation in the case of deceleration during the "unloading motion" were confirmed by experiments. Conducting experiments, we found that the value of the potential of the surface of the erector spine was increased during slow down motion. This result indicates that the lumbar burden can be increased by decelerated motion. This study showed the effectiveness of the dynamic evaluation method by surface muscle potential.

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This paper proposes a candle-like microneedle electrode for electroencephalogram (EEG) measurement from the hairy part of the scalp. In the previous report, we successfully measured EEG from the frontal pole by using a polymer-based dry microneedle electrode. However, this electrode could not measure EEG from the hairy part of the scalp because hairs obstructed contact between microneedles and the scalp. Therefore in this paper, we fabricated candle-like microneedle electrode which can avoid hairs. The pillars help the micro-needles to avoud hair and reach the scalp surface. We experimentally verified that the candle-like microneedle electrode with pillars of 0.6 mm diameter could effectively avoid hairs and measure EEG from the hairy part of the scalp. We believe that this dry electrode, which is mechanically robust, can measure EEG from any parts, and does not need any skin preparation, is readily applicable to EEG measurement for medical and ICT applications.

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Diffuse optical tomography (DOT) is a key technique for evaluating a tumor location and for obtaining muscle function imaging. DOT algorithm consists of the forward model and inverse analysis. The forward model calculates light transmittance in biological tissue at given optical properties. In the inverse analysis, optical properties are evaluated by minimizing a difference between measured profiles and calculated profiles of light transmittance. Recently, the Radiative Transfer Equation (RTE), which is an accurate forward model, has been applied to DOT. However, DOT based on the RTE requires high computational loads, resulting in the application to small animals. To overcome the difficulty, we propose an efficient technique to calculate light transmittance by combining a numerical solution with an analytical solution of the RTE. The proposed technique has the following two steps: 1) light transmittance is numerically calculated in initial values of the optical properties. 2) a variation of light transmittance in change of the optical properties is calculated using an approximation based on the analytical solution. To confirm a validity of the proposed technique, we investigate the variations of light transmittance in a two-dimensional homogeneous scattering medium with the optical properties of human muscle. We can show the variations calclulated from the proposed technique agree will those from the RTE. Thess results indicate the usefulness of the proposed technique for the forward model of DOT.

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In this study, the method to measure the deformation at the surface and inside of a mattress was developed. The mattress with contrast media on and in it was manufactured, and the manikin in imination of the shape of the human trunk, of which the weight was equivalent to the human one, was manufactured by photo fabrication. The mattress with the manikin on it were photographed by X-ray CT. It was confirmed that the CT images had the phantom of contrast media and the mattress deformation state could be visualized. The coordinates of positions equivalent to the centers of gravity of contrast media were acquired from image processing. This process enabled us that deformation state of the mattress was evaluated using numerical values. The plane shape at the mattress surface contacting the manikin was almost the same as the shape of the manikin. Thus, the digitizing precision of our method was estimated by comparing the shape of the manikin with the digitized result, showing the precision was about 2.4mm.

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The objective of this paper is to develop an estimation methid to extract wrist joint angle from a deformation of the forearm skin surface based on muscle contraction. We have been focused on the muscle bulge movement longitudinally along the forearm that derived from muscle contraction. We confirmed on to one relathinship between the muscle bulge movement and wrist joint angle and validate the feasibility to estimate joint angle using this relationship. However, the relationship is difficult to identify because of the misalignment of the sensor to a position of the muscle. Therefore, in this paper, we use the tactle sensor that can measure three-dimensional data of the foream skin surface for considering the estimation method from a muscle bulge mapping. We measured the large area (32[mm]×96[mm]) on the foream skin and the sensor has 48 distance sensor in this area. We calculated x and y coordinates of center of gravity from the measured data for deriving an equation that express the wrist joint angle. We compared the RMSE of estimated angle between the equation that uses x and y coordinate of the COG and the equation that uses only y coordinate of the COG. From the result, RMSE using the equation that uses only y coordinate of COG was smaller than anothre equation. Finally, we validated the fesibility of the estimation method that uses y coordinate of the COG from the measured data by tactile sensor. However, further research is needed to reduce the estimation error by improving the extraction of the relate expression.

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Monitoring of scratching motion, accompany with itchiness, is important for the medical treatment of skin diseases associated with itchiness. In previous study, the sensor system for measuring human scratching by scratch sound is developed and the relationship between the scratch sounds and the mechanical characteristics of human scratch motion was investigated. However, evaluation of human scratching motion against their own skin is not enough, because it is difficult to measure the contact force against human skin during scratching human skin. Therefore, in this paper, in order to measure the contact force, such as pressing force and shearing force of human scratching motion against their own skin, a contact force estimation method using three dimensional motion measurement system is proposed. In experiment, motions of scratching weakly and strongly artificial skin placed on 3-axis force sensor were measured. And finger tip trajectories and deformation of artificial skin were analyzed and compared with contact force. From the result, it is confirmed that the proposed estimation method is available to estimate the contact force during scratching.

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This study proposes an eyeball vibration-type non-contact tonometer using a Point-focus-type Parametric Speaker (PPS). In this method, the cornea is vibrated by PPS using an ultrasonic carrier wave that can cause a low frequency oscillation in a small space. Further, by vibrating the cornea using signals below the low frequency range, the proposed device does not emit any sound to the surroundings. It had been revealed that the amplitude of the vibration to happen on corea decreases with the increase of the intraocular pressure experimentally. However, it was not possible to estimate an accurate intraocular pressure from the cornea vibration; because, a correlation between the amplitude os a cornea vibration and the intraocular pressure amplitudes was low. This problem occurred due to an insufficient investigation of the characteristics of PPS in the previous study. In this paper, the results of measuring an exact sound pressure distribution of PPS are reported.

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