A vibration-driven electret generator has been developed. By using parylene as the spring material, a high-aspect-ratio spring with low-resonant-frequency is realized. Large in-plane amplitude of 0.5mm at the resonant frequency as low as 63Hz has been achieved. Aprototype generator with a seismic mass of 11.6×10.2mm^2 is fabricated through MEMS technologies. Fluorinated amorphous polymer CYTOP is used as high-perfomance polymer electret material. With the present early prototype, we have obtained output power of 1μW at the resonant frequency of 63Hz.

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We used metal thin films prepared by a simple MEMS technique for temperature measurements. We calibrated the decreased thermoelectric power of metal thin film thermocouples (TFTCs), and used those for measurements of temperature distribution at microscopic area. We applied the TFTCs to the Scanning Thermal Microscope (SThM) for developments of temperature measurements. We used metal thin film for thermal conductivity measurements of thin films as both a micro-heater and a temperature sensor called 3ω method. The mechanisms of thermal conductivity reduction of nano-structured materials can be discussed through thermal conductivity measurements at low temperature.

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Recently, the necessity of high Knudsen number flows, such as highly rarefied gas flows with large mean free path and gaseous flows around nanodevices with small characteristic length have increased significantly. In this paper, we describe mainly the optical diagnostic techniques for the high Knudsen number flows, such as laser induced fluorescence (LIF), resonantly enhanced multi-photon ionization (REMPI) and pressure sensitive molecular film (PSMF), and our experimental results obtained by the use of the techniques, i.e., applications of LIF to visualization of flow field structures including complicated shock wave system and to a measurement of rotational temperature, establishment of a REMPI system and its application to detection of rotational nonequilibrium in highly rarefied gas flows, and development of the suitable PSMF for low density and micro-scale gas flows.

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This paper briefly reviews researches on miniature gas turbine generators performed to date in the world. Two major approaches; MEMS-based and mechanical-machining-based approaches are described. The first approach was proposed by Massachusetts Institute of Technology (MIT) in 1997. A lot of outstanding outputs were produced by MIT, but the MEMS-based coin-sized engine has not been demonstrated to date. This paper discusses main three challenging issues of this type of engine. The second approach was taken by at least several groups. The main challenging issues are similar to those of MEMS-based engines. In 2007, Tohoku University and IHI with collaborators established the heat cycle of a juice-can-sized engine with a compressor impeller of 16mm in diameter. This is the world's smallest operating gas turbine engine that has been reported in open literatures.

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Advanced bulk micromachining using aqueous pure and Triton X-100 [C_<14>H_<22>O(C_2H_4O)_n, n=9-10] added 25wt% tetramethylammonium hydroxide (TMAH) solutions is presented in order to extend the range of MEMS structures realized by wet etching. Fabrication processes include two-step wet etching, local oxidation of silicon (LOCOS), and silicon direct wafer bonding. A wide range of both fixed and freestanding MEMS structures are fabricated. The fixed structures such as rectangular and circular corrugations, square and circular shapes trays, etc. contain perfectly sharp edges and corners. The freestanding structures such as cantilever, microfluidic channels, etc. are fabricated using thermal oxide and single crystal silicon as materials.

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We present a micro-machined micro ion sources for flexible and concurrent MEMS processes adequate to production of multiple models in smaller lots. The ion source using the B.K. (Barkhausen-Kurz) oscillation was successfully fabricated by using micro-machining. An ion beam current up to several μA was successfully generated from the B.K. type micro ion source unit having φ1mm×4.37mm discharge space.

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In the present study, we have proposed the flexible piezoelectric sensor by weaving functional fibers with piezoelectric thin films. The flexible piezoelectric sensor is composed of conductive fibers as warp and functional fibers with piezoelectric thin film and patterned electrode as weft. Applying force onto patterned electrode generate voltage through piezoelectric effect. By scanning voltages of nodes of warp and weft, the flexible piezoelectric sensor can work as touch sensor. We have applied die coating, which hes been utilized for protective layer of optical fibers, to realize high-speed PZT thin films deposition on fibers. 1μm thick PZT thin films has been successfully deposited on 200μmφ stainless fibers by die coating.

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Injection molding intrinsically has advantages of high throughput and flexibility of the replica shapes, as you can see that various industrial components and machine parts made from polymer are produced by using injection molding. However, nanostructures, especially with fine and high-aspect-ratio nanostructured surfaces, are hardly replicated by injection molding, because a solidified skin layer is formed on the polymer surface at the moment the melted polymer contacts the mold surface. In this note, we introduce the heat-assisted injection molding, in which the mold surface is dynamically heated during polymer injection. This process realizes as short cycle times as conventional injection molding and as high replication factors as other thermal nanoimprint technique, in which the polymer plate is pressed by a mold and heated over its glass transition temperature. We show the replication of 800-nm-pitch and 350-nm-depth line-and-spaces. And 90-nm-pitch line-and-space and 180-nm-pitch hole patterns were also successfully replicated within 15s using this method.

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A new method to fabricate permanent microstructures in hollow fiber-shaped substrates utilizing the flow patterns generated by the multiphase flows in microchannels was proposed. Regularly arranged cellular microstructures in capillary tubes are obtained by generating a monodisperse slug flow consisting of a curable liquid resin material to be used as the solid partitions and an insoluble fluid material to fill the cellular structures, then petrifying the flow pattern by curing the resin. Experiments were performed using a UV-imprinting resin as the structural material fluid, and a T-junction with the inner diameter of 150μm as the mixer. Fabrication of arrays of cellular microstructures in capillary tubes confining either Nitrogen gas or DI-water was successfully demonstrated.

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Micro-plasma actuator is promising for active flow control because of large induced velocity without any moving parts. In the present study, MEMS plasma actuator has been developed and its mechanical and electrical responses are characterized. Experimental data for induced flow pattern and discharge current are in accordance with previous results using macro-scale devices. It is found that the optimal frequency for energy conversion efficiency depends on the electrode width. The maximum energy conversion efficiency is about 0.1%, which is much larger than that of macro-scale counter part. The present result also indicates that the energy conversion efficiency increases as the thickness of dielectric substrate decreases.

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Optical (far infrared) and thermal properties of a copper nanostrip array on silicon substrate were investigated. It acted as a coupler between the radiation and heat on the surface as non-radiative components (phonon or plasmon polariton at the surface), aiming to enhance outward heat flux from the surface as a cooling device via radiation heat transfer. The emission spectrum of the heat radiation was controlled by the nanostrip array that was designed as the local plasmon and phonon resonant conditions. In the experiment, it generated the temperature gradient of 1.3K across the substrate thickness (0.5mm) when the substrate was contacted on the heater (42℃) in the atmosphere at 26℃.

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This paper reports development of novel micro fluidic device using surface acoustic wave (SAW). The device can control micro channel flow with flow rate ranging from 1.5 to 700nl/min. We found that two different driving modes exist depending on the channel height. Also reported here is how liquid droplet motion changes by experimental conditions.

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A new viscosity sensor enabling non-contact measurement at high speed, with less sample volume and high stability is required in a broad field. For example, in the industrial field, process control by in situ measurement of viscosity can enhance quality and process yield of ink, paint and coating films. Therefore, we have developed a new miniaturized optical viscosity sensor, namely MOVS (Miniaturized Optical Viscosity Sensor), based on a laser-induced capillary wave (LiCW) method which can meet the requirements above. MOVS measures viscosity by observing damping oscillation of laser-induced capillary wave (LiCW), which is generated by an interference of two excitation laser beams on a liquid surface. MOVS consists of five U-grooves fabricated by MEMS process and optical fibers. The newly integrated optical surface tracking system makes possible the stable viscosity measurement under external disturbances such as vibration and evaporation. In this study, by integrating the optical surface tracking system, nanosecond damping oscillation of LiCW is successfully observed in the presence of external forced vibration drying process of a liquid film (thickness of hundreds micrometer order).

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Measurement of temperature distribution at nanometer scale is important for the thermal design of high integrated devices. However, in conventional optical measurement techniques, the spatial resolution is limited by the diffraction limit of light, which is approximately half of the wavelength of the optical beam. Therefore, we have developed a novel optical temperature measurement method in nanometer scale using near-field microscope technique. We newly employed the polarization of light into the measurement principle, since the near-field polarization has a high sensitivity for the refraction index of the sample, which varies with temperature. In this method, the near-field optical fiber probe which can maintain the polarization state is necessary for increasing the measurement sensitivity. Hence, we have newly fabricated the single mode near-field optical fiber probe. In this paper, we report the verification of the new measurement principle and the comparison of the measurement sensitivity with the results using temperature dependence of reflectance.

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The purpose of this research is to develop the multi-functional thermal analysis system, where fast thermal analysis and resonance mass analysis are conducted with SEM observation using a tiny cantilever type calorimeter. The developed calorimeter can conduct a fast DTA of temperature scan rate over 10000K/s and mass measurement of nano-gram sample by detecting mechanical resonance of the cantilever. In this paper effects of air on the thermal and mass analysis with the calorimeter were experimentally investigated. Moreover, simultaneous thermal and mass analysis test with tiny copper sulfate pentahydrate showed sub-microgram dehydration process in a continuous fast temperature scan operation.

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The objective of this study is to investigate heat transfer mechanism of pool nucleate boiling with MEMS (Micro-Electro-Mechanical systems) sensor fabricated for boiling research. Temperature variation beneath an isolated bubble under nucleate boiling condition of saturated water was measured with the sensor. Measured temperature data presents microlayer evaporation and expansion of dry-out area in bubble growth process and rewetting of the dry-out area in bubble departure process. Heat transfer from the heated surface was evaluated by calculating local heat flux by transient heat conduction simulation with the measurement data as a boundary condition. It is shown that high heat flux, induced by the microlayer evaporation, on the order of MW/m^2 was observed in the local heat flux distribution. The heat transfer enhancement by the microlayer evaporation was much larger than that by the rewetting, microlayer evaporation contributed mainly to the heat transfer from the heated surface to the boiling liquid and vapor phase. From the evaluation of the total surface heat transfer, transferred heat from the surface corresponded to about half of the latent heat of vaporization in the bubble.

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Scattering process of gas molecules on vertically aligned single-walled carbon nanotube (VA-SWNT) films was investigated using molecular beam technique. The surface modification with VA-SWNT films was found to significantly enhance energy accommodation of helium molecules, which tends to be inefficient even on contaminated or rough surfaces because of the large mass mismatch between helium and surface atoms. Our results indicate that the surface modification with VA-SWNT films is promising for enhancing heat transfer across surfaces in micro/nanoscale devices. The efficient energy transfer originates from high porosity of the films, which enables gas molecules to penetrate into the film and have multiple collisions with SWNTs. In order to reveal the scattering process within the film, we also conducted the measurements with freestanding VA-SWNT films. Even for the film as thin as 0.1μm, most of the molecules are well accommodated and are reflected or transmitted diffusively through the film while few molecules are transmitted without any interaction.

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The influence of 11-mercapoundecanol (-S(CH_2)_<11>OH) self-assembled monolayer (SAM) on the interfacial thermal resistance at the interface of Au(111) and water was investigated using nonequilibrium molecular dynamics simulation. As a result, the interfacial thermal resistance at the interface of Au-SAM-water was found to be higher than that at the interface of Au-water. In addition, the local interfacial thermal resistance at the interface of SAM and water was found to be very small. We analyzed the hydrogen bond at the interface of SAM and water and found that the most of hydrogen bond provided by the SAM molecules are connected to water molecules, and that they would effectively contribute to the small local interfacial thermal resistance at the interface of SAM and water.

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Recently, the microfluidic device such as μ-TAS has been attracted in many fields. Since surface forces become dominant with decreasing of a length scale, it is difficult to remove the bubble attached to the channel in a device. An unexpected adhesion of a bubble causes the large pressure loss or deterioration of the device. We have suggested the noncontact bubble manipulation method using photothermal Marangoni effect. When the fluid in the vicinity of the bubble is irradiated by the laser and local temperature gradient is induced around the bubble, Marangoni convection along the gas-liquid interface occurs due to the surface tension gradient. As a result, the bubble migrates to the laser spot and scanning of the laser spot enables transportation of the bubble. In this paper, the migration behavior of the bubble along the channel was investigated. We also obtained the minimum optical power for the manipulation with different conditions of bubble sizes, scanning speed and kinematic viscosity of liquid. Experimental results can be summarized by a dimensionless number which means a ratio of thermocapillary force to viscous drag force. Universal criteria on migration are indicated by the dimensionless number.

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In this paper, we studied basic characteristics of the SAW propagation. When periodic micro structures were formed on the SAW transmission region, the propagation characteristics were dynamically changed. The prototype devices based on this analysis were fabricated and demonstrated. Conventional SAW elements were consisted of IDTs on the piezoelectric material and its transmitting frequency was just determined by the pitch of the IDTs. The periodic micro structures formed on the SAW transmission region can modulate the SAW propagation. Since periodic micro structures are controlled dynamically using the MEMS techniques, phase, frequency and transmitting power of the SAW can be modified.

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The removal effect of a humidity swing operation on suspended particulate matters (SPM) was experimentally studied. The experimental results show that the humidity swing operation increases number of SPM less than 5μm size and decreases that of more than 5μm size. Also, a large number of liquid droplets were found in a deposited matter collected by inertial impact method after the humidity swing operation. We concluded that the nuclear condensation takes place on the SPM in the supersaturated moist air during the humidity swing process. It is expected that new whole SPM removal method can be proposed, where the SPM grows to several micrometer size by the nuclear condensation, and then the grown particles can be removed by gravitational or inertial effects.

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The manipulation of small objects is difficult in micro scale, because surface force is more dominant than body force. Adhesion force between the objective and a manipulator tip due to electrostatic, Van der Waals or meniscus force makes a pick-up motion easy but a release motion difficult. Thus, we invented a "meniscus tip" with a variable adhesion force feature. The meniscus tip, having small heater on water filled capillary tube, can control the adhesion force through varying wet state of the tip by supplying or drying water. The variation of the adhesion force of several micro-Newton was measured by a movable coil voltage meter adapted to a force measurement. Additionally, the micromanipulation of small glass beads was demonstrated.

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This paper describes a flapping robot based on a dragonfly. Flapping flight enables the robot to hover and take a sharp turn like an insect. The flapping motion was produced by a four-bar linkage and a slider-crank mechanism actuated by a DC motor. The body of the robot was fabricated from a brass plate using MEMS techniques. The brass plate was patterned by etching, and then folded out of the plane to assemble the three dimensional structure. The wing with veins was also microfabricated from an aluminum plate and a parylene film. The robot flapped at 12.4Hz and generated the lift force of 7.21mN.

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This paper discusses a biomimetic water strider robots that is fabricated using MEMS (micro electromechanical systems) techniques. Lift, pull-off and thrust forces of the supporting legs have been measured. The robot has a "origami structure" that is assembled by folding a flat brass plate. The robot successfully walked in the tripod gait at 300mm/min, and also moved on the surface of water at 600mm/min.

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In order to achieve improving both performance of curve-passing and critical speed of hunting motion for railway vehicles, the assist steering system that builds the actuator function into mono-link type primary suspension has been developed. As a result of the running test, outer side lateral force of the leading axle in a circular curve section was decreased by about 30% by adoption of the developed system. However, the running test results on the test track remained different from those on a typical commercial line because of the restriction of the alignment of the test track and the test vehicle's performance. Therefore, quantitative examinations of the lateral force reducing performance in high speed running situation, and the influences of the lateral force increase on inverse steering condition were carried out with the bench test device that is able to simulate the running condition in a circular curve section of the commercial line. In the bench test, this system could achieve 70 to 90% decrease of the turning lateral force compared with the passive condition. It has been recognized that the turning lateral force would not be affected by the radius of the curve section and vehicle's running speed, but be affected only by the geometrical factor. Moreover, the mechanical reverse-steering prevention strategy that was established based on the characteristic of the assist actuator's inner structure and the longitudinal creep force was studied. In addition, the authors report the stability confirmation of bogie hunting motion during operation of the assist actuators.

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The comb structure between cleats in adjoining steps is one of the safety features in escalators. It prevents the biting of shoes, hands and feet between adjoining steps. This comb structure is between the riser cleat in the upper side step and the demarcation comb in the lower side step. Now, the depth of overlap of the comb structure in the upper side of the riser is gradually reduced over that in the lower side of the riser to make for easy exit when shoes, hands or feet are bitten between steps. This method greatly contributes to the prevention of nasty accidents. On the other hand, this ease in exit also makes it easier to be bitten in the upper side of the riser. Therefore, as one idea, safety improvement by making it more difficult to be bitten by deepening the engaging in the upper side of the riser is a likely area for study. In this paper, the riser cleat shape and step composition are examined with the view that "it should not ever be easy for shoes to be bitten between steps". As a result, if you follow this view, the overlap depth should be enlarged in the upper side of the riser.

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One of the major causes of the tire coming-off accident of large vehicles is that wheel bolts, which clamp inner and outer wheels to the hub, are not necessarily tightened with prescribed torque. The amount of torque is a practical index to clamp the joint with its target bolt preload. In the past, tightening operation was conducted by an impact wrench, which cannot control the tightening torque with sufficient accuracy. In order to reduce the number of such accidents, the use of a manual torque wrench has strongly been recommended since 2003 by Ministry of Land, Infrastructure, Transport and Tourism. However, the tire coming-off accident still occurs rather frequently. That is because all the tires of large vehicles have not always been tightened using manual torque wrenches due to the low working efficiency, since the total number of tightening operation is usually 80 times and higher when clamping a lot of wheel bolts one by one. In this study, tightening apparatuses with torque control mechanism, especially designed for wheel bolts of large vehicles, are developed aiming at the extermination of tire coming-off accidents. A tightening device, called "air wrench", is used as the key device to design the tightening apparatuses. Air wrench has been used to tighten large bolts with prescribed torque in some industrial fields. First, the performance of air wrench is examined concerning the accuracy of bolt preloads and the scatter in coefficients of friction at mating surfaces. Then, tightening apparatuses equipped with two or four air wrenches are designed, which can tighten two or four wheel bolts simultaneously. It is shown that the developed tightening apparatuses provide high working efficiency and low scatter in bolt preloads.

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One of the important issues on the Sequential Approximate Optimization (SAO) is the sampling strategy. The sampling strategy for SAO using the Radial Basis Function (RBF) network is proposed in this paper. The proposed sampling strategy consists of three parts, which are called the density function, the boundary function, and random sampling. In order to add the new sampling points effectively, the density function and the boundary fuction are constructed by the RBF network. The objective of the density function is to find the sparse region in the design variable space and is to add the new sampling points in this region. In the constrained optimization problems, at least, one or more constraints will be active. As the result, it is desirable to add the new sampling points on the constratins. The objective of the boundary function is to add the new sampling points on the boundary. In addition, the random sampling is also introduced to spread the search region. The algorithm of proposed sampling strategy is described in detail. Through the numerical examples, the validity is examined.

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The impacts between structural elements are often happened in engineering applications. There are many types of impacts in such situations. Among them, direct central impacts between two spheres are one of the most basic impact configurations. So far, several expressions for the coefficient of restitution have been proposed by K.L. Johnson, W.J. Stronge, C. Thornton, but they mainly focused on the impacts between two spheres made of same materials. This paper investigates the influence of material dissimilarity on the impact properties in detail. The experiments between spheres made of aluminum and steel were conducted. Then the numerical simulations have been carried out by using Finite Element Method. The results were compared between the experiments and simulations and they agreed well. In the present study, the deformation concentrated on the aluminum sphere. Further, the profile of the contact surface became concave. For the impact between spheres made of dissimilar materials, the concept of composite coefficient of restitution has been successfully applied to several experimental results so far. According to the composite coefficient, the coefficient of restitution for the dissimilar materials should take the intermediate value between those for the same materials. However, the coefficient of restitution for the dissimilar impact was lower than those of the same materials in the present study. It is thought that this discrepancy is caused from the assumption of flat contact surface in the composite coefficient of restitution, while it was concave as seen in the results of this paper.

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Fractional derivative finite deformation theory and nonlinear finite element method were developed for evaluating dynamic characteristics of viscoelastic bodies used in shock and vibration reduction. Fractional differential orders from the static and dynamic testing of viscoelastic material with small strain were obtained. Then a fractional derivative constitutive model for finite deformation theory was constructed and nonlinear finite element equations of motion, involving a newly developed viscoelastic damping matrix as well as standard mass and stiffness matrices, were formulated. Based on this work, a nonlinear finite element computer program for the evaluation of vibration characteristics of viscoelastic products was developed. Simple numerical examples were computed and compared with the experimental results. Both results are in good agreement.

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Dynamic wind-tunnel tests on a simplified car model, known as the Ahmed model, were conducted using a two-degree-of-freedom model shaker. Time-resolved aerodynamic forces were directly measured with a built-in six-component balance in sinusoidal heave or pitch motions with forcing frequencies up to 8Hz depending on the motion type. The results show that frequency-dependent magnitudes and phase differences between the model height/angle and the aerodynamic forces are in close agreement with those predicted by large-eddy simulation (LES) using an arbitrary Lagrangian-Eulerian (ALE) method. On the basis of these results, an unsteady aerodynamic force model is constructed in the form of transfer function on the assumption of linear system. The force and moment fluctuations associated with vertical motions are well described by the linear force model that integrates virtual mass and moment-of-inertia terms into the quasi steady model which expresses the posture changing rate in the form of the relative inflow angle.

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A numerical method is proposed to calculate damping properties for three-dimensional sound proof structure including elastic material, viscoelastic material and porous material. Displacement vectors as common unknown variable are solved under coupled condition. Further, explicit expressions of modal loss factor for the three-dimensional sound proof structures are derived using asymptotic method. Using this technique, eigenvalue analysis and frequency response analysis are performed for automotive double walls with a porous material. Further a spacer installed between a steel panel and sheet in the double walls to analyze deterioration of vibration.

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Modal differential substructure method that can quickly predict the effects of structural modifications has been proposed by the author. This method is a kind of the component mode synthesis and utilizes the reduction of degrees of freedom for unmodified parts. For calculation accuracy improvement of the proposed method, a combination with the static condensation (Guyan reduction), which is similar to the fixed-boundary dynamic reduction, is investigated. The formulation is a generalization of the component mode synthesis method which can be combined with any kind of deformation patterns. The prediction accuracy and efficiency depend on deformation patterns used for the coordinate transformation. More accurate reduction components are generally obtained with modes under boundary conditions similar to the assembly.

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Designing low noise elevator cars has become an important issue. Elevator car noise is caused by aerodynamics and the elevator traction machine. The noise under 1000Hz that radiates from a elevator traction machine is a particular problem because it is not easily insulated by the elevator car's walls, the structure of elevator traction machines differs from that of general electric motors. Hence, a noise evaluation method for the elevator traction machine has been developed. First, we conducted an excitation test with an excitation machine, the results of which showed the vibration mode. Then we designed the numerical model on the basis of the excitation test results and calculated structure-borne sound radiated from the elevator traction machine excited by electromagnetic force. This force was obtained from magnetic field analysis using measured current and computed Fourier transform of the time domain and the space domain. As a result, we show how calculated results matched the measured results well. We also show the space order of the excitation force that had a large influence on the noise radiated from the elevator traction machine.

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In this paper we propose a model for sound-absorbing poroelastic materials using the homogenization method, based on the asymptotic approach. In contrast to the conventional Biot's model which is empirical and is not linked with the microstructure, the proposed model is consistent with microscopic structure and yields a macroscopic governing equation with properties predicted directly from microscopic geometry. In this model, four properties for the solid phase and two properties for the fluid phase are calculated by averaging characteristic functions of the periodic microscale model. These properties are then substituted into the macroscopic governing equations to evaluate performance such as the sound absorption coefficient for normal incidence. The proposed model is reduced to an equivalent monophasic model, i.e., an elastic solid model when the pore size is infinitely small, and a fluid model governed by the Helmholtz equation when the bulk modulus of the solid phase is sufficiently high compared to the bulk modulus of the fluid phase. Utilizing two-dimensional models with simple microscopic geometries where analytical solutions of sound absorption coefficients for normal incidence can be obtained, we show that the proposed method can provide accurate numerical solutions that converge to solutions obtained analytically as the discretization parameter of the microstructural model is made smaller. We also show how the actual size of the microscale affects the sound absorption coefficient, using a three-dimensional microstructure model.

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The motion and vibration of a moving body running on a complicated 3 dimensional (3D) trajectory considering resistance to forward motion are investigated in this paper. A roller coaster is treated with here as a concrete example of moving body. The equations of motion of a roller coaster in which a trajectory and a vehicle are coupled are derived by using differential-algebraic equation (DAE). By using these equations, a time history simulation analysis is performed. The dynamic behavior of a roller coaster which moves forward due to the gravity is investigated. The effect of an air resistance and a rolling resistance are taken into consideration in this analysis. Also, the motion and vibration experiments have been performed using an actual roller coaster in site. The acceleration responses in simulation are compared to those in experiment. Both show a good coincidence qualitatively. Moreover, influences of running resistances on the required time from the starting point to the arriving one are made clear.

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This paper presents a novel transparent smart film actuator based upon a conductive polymer. Conventional smart sensors and actuators were fabricated by opaque materials such as aluminum electrode. Because of opacity, their applications were restricted to a specific area. To overcome such problems, this paper introduces a conductive polymer Poly(3,4-ethylendioxythiophen)/poly(4-styrenesulfonate) (PEDOT/PSS) for electrode, the result that the PVDF film becomes a transparent distributed parameter actuator per se, hence transparent smart material fit for optical flexible device is developed. Firstly, this paper overviews conductive property and transparency of conductive polymer. Then two-dimensional modal actuator film for exciting specific structural mode is proposed. Furthermore, a conductive polymer-based cantilever beam entailing the capability of modal actuating is developed, the validity of the proposed transparent smart film actuator based upon a conductive polymer being analytically as well as experimentally verified.

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This paper concerns global control of the total energy and power of a structural and acoustic field of a generic dynamical system. In light of the magnitude of state variables; structural kinetic energy, acoustic power in the outer space and acoustic potential energy in the inner space of an enclosure, a total performance index is introduced such that each state variable is to be evenly dealt with. The orthogonal contributors, termed vibro-acoustic modes, responsible for the total performance index are then derived. With an aim to extract the vibro-acoustic modes, a vibration-centric spatial filter is introduced, which is found to be frequency dependent. To overcome this impracticality, a fixed modal filter is presented, the viability being investigated. Once the filtering methodology is established, the actuation methodology is similarly achieved due to the duality in between. Finally, a numerical analysis is conducted, demonstrating the capability of achieving global control of the total energy and power of a dynamical system.

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Open loop control for the tower crane whose length is time varying is proposed to reduce the residual response amplitude. Different from traveling crane, because the system is described as 2 degrees of freedom system even in the case without variation of the length, a special strategy is required in the design of the acceleration pattern for the open loop control. By introducing the nonlinear time scales, we modify the acceleration pattern in the case without time-variation of the length proposed in our pervious research. We carry out the open loop control by applying the proposed acceleration pattern. We perform the numerical simulation for the analytical model whose validity is experimentally verified. The comparison of the residual amplitude under the conventional method and the proposed method shows the effectiveness of the proposed control method for the practical use.

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This paper investigates amplitude modulation (AM) of a relatively long-cycle vibration when excited by a double belt in a belt-driven centrifugal fan. Since the inner belt is stretched more than the outer belt due to the longitudinal difference in bending displacement of the overhung shaft by the pulley, tension and rotational speed of the inner belt are greater than for the outer belt. Two types of V-Belt excitation occur as a result of the small difference in rotating speeds of the belts, and cause amplitude modulation of the vibration during fan operation. On the other hand, the previous investigation confirmed that V-Belt excitation due to belt joins incorporates some higher harmonics. Superposition of amplitude modulation due to each higher harmonic was observed, and it was therefore concluded that measured data were consistent with calculated data based on the results of the previous investigation. Furthermore, it was shown that there is an amplitude modulation of the vibration in the tested fan, consisting of the amplitude modulation due to first, second, fourth and sixth order components corresponding to the rotational speed of the belt.

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Power assist devices have been introduced to reduce physical burden of workers in conveying and mounting work in industries. Most of them handle controlled objects as rigid bodies. This paper discusses an effective vibration control method for conveying flexible structures with power assist. In this study, the power assist is realized by an impedance control method. The impedance characteristics of the power assisted object correspond to the dynamic characteristics of the disturbance for the vibration control. Our previous paper discussed a disturbance accommodating LQ optimal control (DAOC) method for the vibration control problem and the effectiveness was verified by state feedback control simulations. In this paper, the DAOC method is applied to the same cart with a 1-DOF vibration system as in the previous paper but having more flexible structure. The effectiveness of DAOC in this paper is demonstrated through actual experiments on the basis of output feedback control implementation.

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In industrial production lines, there are many operations by not only autonomous machinery as industrial robots but also man-machine cooperative systems as power-assist systems. There are many flexible and large parts because of being lightened, which cause vibration during operation. In such a case, efficient mode switching from machine-oriented operation to human-oriented operation and vibration suppression are important issues. This paper presents an assist control method for task from automated conveyance to manual positioning of a flexible part. This method consists of the smooth mode switching compensator whose control input is continuous at the controll mode switching, and the input shaping compensator which is used to suppress the vibtation of the flexible part. The notch filter with a variable gain is used as the input shaping compensator, which eliminates the vibration frequency component of the flexible part from operating force signal. The effectiveness of the proposed method is verified from standpoints of maneuverability and operating feel. The former is based on the evaluation of the time responses and the success time of the task, and the latter is the subjective evaluation of the operators using questionnaires.

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A small mobile robot with automatic welding system of steel plates was developed. It has functions of automatic seam tracking and weld penetration control. The image of welding lines including straight and angled line were acquired by CCD camera that was set on tip of the robot arm. The welding line was detected by applying some image processing to the image. In this welding robot system, acceleration and deceleration of welding speed are conducted to reduce welding process time. In this case, welding current is controlled in accordance with the speed change to keep the weld penetration optimum. The control system was constructed using Neural Network in which geometric parameters of the molten pool were inputted to the input layer and the optimum weling current was outputted to the output layer. The geometric parameters of the molten pool are obtained by applying the image processing to the image captured by another CCD camera. The effectiveness of the mobile welding robot system was confirmed by some welding control experiments.

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Parametrically excited dynamic bipedal walking is an effective approach for a robot to restore its mechanical energy that is lost during the exchange of a leg's swing phase to the stance phase. Based on the parametric excitation principle, we succeeded in developing an experimental walking robot and realized for the first time the dynamic walking by the robot. In detail, the biped robot consists of four parallel legs with prismatic joints driven by DC motors so as to constrain its movement in a 2D plane. Each set of two inside or outside legs is physically jointed by a synchronous shaft and connected with the other set at the free rotational hip joint. The foot of each leg has a semicircular shape that has an effect to increase the walking speed without considering the zero moment point problem. By introducing an unique counterweight mechanism, it is shown that we can improve the Specific resistance, Restored mechanical energy and Walking soeed. Experimental studies and simulations show the effectiveness of this walking robot.

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In this paper, we propose a distributed cooperative scheduling approach for flexible flowshop manufacturing system. This method breaks up the system into each process, and they are integrated as a single system. Since each process needs only local information, it is effective to apply the method to the large production system. Our approach focuses on lotsizing problem as well as manufacturing scheduling concurrently with Lagrangian decomposition and coodination method. We try to compare our method with conventional distributed cooperative method and centralized method, and show the effectiveness of the proposed concept.

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Tooth contact evaluation has been conventionally performed visually by the machine operator in the gear manufacturing fields when finishing a gear or at assembly. With automation, the boundary of the contact area is unclear due to scattered light when visible light is used to obtain an image to evaluate tooth contact. We have therefore focused on the use of a near-infrared to prevent scattered light. First, a suitable wavelength is investigated to obtain a fine tooth contact image in near-infrared vision. Second, it is confirmed that the tooth contact image obtained by image binarization is hardly affected by the image threshold. Third, we propose a new method to extract the boundary part of the tooth contact by differential calculation of the fine near-infrared image. These methods make it possible to automatically divide a near-infrared image into the contact area, the boundary and the non-contact area. Finally, the obtained result is compared with the tooth contact calculated from the measured tooth surface. As a result, we demonstrated that the near-infrared image method is effective for automatic tooth contact evaluation.

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The DNA chip is required of high sensitivity and low cost for practical medical service. We have tried to use polycarbonate (PC) included TiO_2 as a substrate of DNA chip for low cost. However, the PC included TiO_2 cannot adhere DNA easily due to their hydrophobicity. In this work, in order to change the PC included TiO_2 to be hydrophilicity, At, N_2 and O_2 ions were irradiated on the surface of specimen by using an Electron Cyclotron Resonance (ECR) ion shower apparatus. We measured the contact angle of water on the surface of specimens with an optical microscope. Surface morphology of specimens were observed by a SEM, and measured by an AFM. Surface of specimen was analyzed by X-Ray photoelectron spectrometry (XPS). Then we measured adhesion force of DNA probe to the surface of specimen by force curve measurement using the AFM in water. The contact angle of untreated specimen were decreased and reached to 8deg. by N_2 and O_2 ion irradiation. The surface roughness of untreated specimen were increased and reached to 248nmRa by N_2 ion irradiation. The hydrophilic property was kept during 1440 hours in air by 2 times irradiation of O_2 ion. XPS showed that hydrophobic groups were formed on the surface of specimens by N_2 ion irradiation. The adhesion force of DNA probe to the surface of specimen was increase by seven times larger than the untreated one by 4 times irradiation of N_2 ion.

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In order to preserve environment and save energy, some resembles using low viscous engine oils have been made. We examined the tribological properties in base oils with low viscosities of 8.3, 17.5 and 78.7mPa・s. Friction test was carried out using a lathe, similar to a block on ring tribometer. Block specimen and ring specimen was the same cast iron. Frictional force and temperature rise were measured. As a result, the type of frictional properties and the type of wear curve can respectively be classified into three. Those types corresponded. It is possible to divide by the classification like H type, T type, and B type. For T type, pressure from which oil is supported has lowered as the viscosity lowers. From the PV diagram, it is understood that the area of H type narrows from L3 of a high viscosity as for L1 and L2 of a low viscosity. Moreover, if L1 is compared with L2, the area of B type is growing in L1. This suggests that the possibility of transition to B type that friction and wear keeps increasing when the viscosity is lowered in excess rise.

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