Many air conditioners use fan systems for heat exchange. Vibratory motion and noise in the conditioner occur when aerodynamic force of the rotating fan blades act on the cabinet of the air conditioner. On the other hand, reaction force corresponding to the aerodynamic force occur, and then the reaction force transmitted to the motor-feet. Finally, these transmitted forces excite support-structure of the motor. In this research, we conducted experiments and discussed the influence of the number of boards which corresponds to the cabinet of an outdoor air conditioning unit to motor-reaction forces. Furthermore, we applied bell mouth to the experimental apparatus and investigated the influence of it. We also performed a computational fluid dynamics (CFD) analysis using fluid flow analysis software PHOENICS, and obtained pressure distribution near fan. Based on the calculation results of pressure distribution, experimental results were considered.

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In recent years, the information society rapidly developed. It is required to increase density of hard disk drives （HDDs）. In order to achieve the high density HDDs, it is important to research details of magnetic disk surface and some properties related with the head-disk interface. However, diamond like carbon (DLC) film on disks have been too thin to analyze chemical structure of DLC surface using Raman spectroscopy. In this study, we fabricated the plasmon lens with the sliver thin film on the surface by the vapor deposition and evaluated the structure change of ultra-thin DLC after laser-heating using surface enhanced Raman spectroscopy with the plasmon lens.

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A new type of sliding probe for clarifying nano-lubrication phenomena is proposed. In the probe, a small glass sphere was attached with a micro structure for force detection. This enabled us to increase the design freedom such as the curvature and material of the sliding surface. In this study, we successfully fabricated the probe and demonstrated the feasibility of nano-rheological measurement for the confined lubricant.

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It has been clarified that liquid lubricants confined in nanometer-sized gaps have different mechanical properties from those in bulk state, and it is necessary to consider these effects on lubrication design. In our previous studies, authors have established high-precision nano-rheology measurement method (fiber wobbling method), clarified that unique viscoelasticity of lubricants in nano gaps. In the conventional measurement, however, the effective contact area between the probe and the lubricant is several square microns, whereas the sliding distance is about several tens of nm. It means that the sample liquid in nano gaps is sheared without being replaced. On the other hand, in actual lubrication between mechanical elements, it is supposed that the sliding distance is sufficiently large as compared with the contact area. In order to measure the viscoelasticity of the lubricant under such conditions, the purpose of this research is to realize a sliding distance of micrometer order while maintaining the nano gaps in viscoelastic measurements using the fiber wobbling method.

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We focus on colloidal liquid used as thermal transport media applied to thermal storage or heat transfer enhancement. Electro-kinetic behavior of colloidal liquid is a key for the heat transfer in these applications, especially at the interface between liquid and solid where heat transfer takes place. We develop a novel measurement technique for measuring the electro-kinetic mobility of colloidal particles particularly in the vicinity of a solid wall. The measurement is based on laser Doppler technique using evanescent waves created on the surface of a glass plate facing at colloidal test liquid. In the present paper, we report on the development of the measurement system and the latest results of the experiments including the initial measurement signals of the system using colloidal particles.

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We fabricated contoured nanostripe (CNS) surface consisting of Cr and Cu multilayer films having a contour like grooves by wet blasting. Depth of nanoscale grooves (nanogrooves) on the substrate is 60 to180 nm. The friction tests at a constant load were carried out using an Al ball under a lubricating condition. The CNS substrate having dense nano-grooves showed the lowest wear. The substrate having nano-grooves showed good lubricating properties. Durability of CNS surface probably depended on interfacial strength between films. The friction loop showed that the CNS surface had locally friction reduction properties.

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Malignant malaria is an infectious disease caused by Plasmodium falciparum in tropical and subtropical regions in the world. P. falciparum invades red blood cells (RBCs) and remodels their membrane. It is well known that the membrane of P. falciparum-infected RBCs (P.f-iRBCs) become indurated as a result of the remodeling. However, this remodeling mechanism remains to be elucidated. Here, we present a tensile test method for RBCs using dielectrophoresis (DEP) that is able to quantify their deformability and can be used to elucidate the remodeling mechanism in combination with biochemical analyses. The deformability of P.f-iRBCs and uninfected RBCs were quantified using this method. We found that the deformability of P.f-iRBCs was significantly lower than that of uninfected RBCs, suggesting that the membrane of P.f-iRBCs become indurated as reported previously. We conclude that this method is useful to quantify the deformability of the RBC and evaluate the RBC remodeling activity of P. falciparum.

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Nanoimprint is a technique to fabricate nanoscale patterns by pressing a mold onto a resin material. In particular, nanoimprint lithography (NIL) using UV curable photoresist is expected to improve a process of semiconductor memory manufacturing in the future. During molding, the photoresist is confined in nanometer-sized gaps (nano-gaps) between the mold and the substrate. Furthermore, in the NIL of the semiconductor memory manufacturing process, high precision positioning of the mold is indispensable, and the photoresist is sheared at the nano-gap. The frictional resistance at this time becomes a factor of lowering the positioning accuracy. Therefore, prediction and control of frictional resistance are essential to improve positioning accuracy. However, it is known that various liquids have characteristic mechanical properties in nano-gaps. In this study, we aimed to elucidate the viscoelasticity of photoresist for UV nanoimprint confined and sheared in the nano-gap by the highly accurate nanorheological measurement method developed in our previous study.

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Dye-sensitized Solar Cell (DSC) is one of the noteworthy devices due to its superior design and low cost process. However, there is a drawback in low conversion efficiency. We are controlling the structure of titanium dioxide thin film used for dye sensitized solar cell for high efficiency by using electrostatic ink jet method which is printing technology. In the currently used electrostatic inkjet method, the large droplets are stacked on the substrate by gravity. In this study, to remove the large droplets nozzle orientation and positional for the substrate are controlled, and we have succeted to form an uniform thin films.

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This study proposes a method of measurement and control in micro cutting process with rotary cutting tools of 30-100μm in diameter using a electromagnetically levitated stage. Because the magnetic levitation can support a stage with work by non-contact, disturbance such as frictional force does not occur and it can measure force produced by micro cutting. Furthermore, the force applied to the cutting tool can be controlled by adjusting the position of the stage depending on the measured force. In this study, an experiment of measurement of the force in micro cutting process using tool of 30μm in diameter are reported.

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Lithium ion batteries are widely used in a variety of portable products because of their high energy density. Recently solid-state lithium ion batteries have been studied to solve the safety issue of liquid electrolyte. In order to realize solid state thin film batteries, we prepared electrode thin films by RF magnetron sputtering on Pt/Ti/Si substrates. In this study, LiCoO₂(LCO) cathode thin films were deposited. After annealing at 620°C, clear diffraction of (003) and (101) orientation was detected in XRD measurements. Si anode, Cyclic voltammgram showed oxidation and reduction peaks at 0.6 V, 0.01 V, respectively. We also measured the capacity of the Si thin film by the discharge-charge curves. The discharge-charge capacity of 660 μAh/(cm²・μm) and 609 μAh/(cm²・μm) could be obtained for the Si anode thin films, respectively.

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This paper describes piezoelectric vibration energy harvester (PVEH). The PVEH was fabricated from Pb(ZrTi)O₃ (PZT) thin films which were deposited onto (Pb,La)TiO₃/Pt/Ti-coated stainless steel substrate by rf-magnetron sputtering. We measured output power of the PVEH as well as theoretical calculation. The output power showed maximum at the calculated optimal load resistance of 73.2 kΩ, where the output power was 1.0 μW. For the purpose of predicting output power, we tried to derive electromechanical coupling coefficient. Applying an equivalent circuit model of the energy harvester, we succeeded in deriving electromechanical coupling coefficient.

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Telexistence is not merely a remote operation but a bilateral feedback system of sensory feeling and force between an agent robot and an operator. This system gives the operator sensations like existing in the remote place actually. By miniaturizing this telexistence system, new applications of the telexistence are available, e.g. the inspection operation in the narrow space where is too small to go workers into there. By using the telexistence system, the operators can operate the agent robot intuitively, operation training is required minimally. Implement the robot middleware; our micro telexistence agent robot can be treated as a HRI (Human-Robot Interaction) component on the IoT system network. In this paper, we report the configuration design, development and evaluation of the micro telexistence agent robot.

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Among the many types of sensors for measuring vibration, the AE sensor is designed to measure acoustic emission, i.e., small-amplitude vibration. Most AE sensors use piezoelectric material as transducers. Compared with the piezoelectric sensors, MEMS sensors have beneficial characteristics such as low cost attributable to mass production and smaller size. The SA sensor is a type of MEMS sensor and has broad frequency bandwidth. Exploiting this characteristic, the SA sensor can be used as a multifunctional vibration sensor to measure several frequency ranges conventionally measured by multiple sensors. In this paper, PLB test results measured by SA and AE sensors are evaluated by wavelet transform to investigate the applicability of the SA sensor for AE measurement.

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Vibration power generation technology is expected as a power supply technology to realize IoT society to widely spread. However, commercial examples are only a few, and they have not yet grown up a big business. In this presentation, we will introduce our vibration power generation technology and describe the issues for big commercialization.

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Surface forces interacting between solids play an important role for small devices such as micro/nanoelectromechanical systems (MEMS/NEMS) or for industrial processes including tribological phenomena. Atomic force microscope (AFM) and surface force apparatus (SFA) are often used to measure the surface forces with ultra-high resolution. In this study, we proposed a new method of surface force measurements using the quartz crystal microbalance (QCM). Combining the surface interaction force tester and the QCM, the surface interaction forces and resonant frequency shift of the QCM were measured simultaneously. The basic characteristics of the relationships between the surface forces and the frequency shifts were obtained using the newly developed experimental system.

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In the data center, which manages a huge amount of information, a hard disk drive which is inexpensive and has a large storage capacity is mainly used. However, since the number of HDD operations increases as information volume increases, it is now required to save HDD power. In response to this problem, development of an air bearing spindle to which an air bearing is applied is being carried out. However, there are no examples that have come into practical use due to low impact resistance and low productivity. In this resear ch, to reduce the dynamic characteristics of the HDD spindle motor, the purpose is to develop a small gas bearing spindle of a new structure. This paper report the processing conditions of bearing grooves by laser processing to obtain the groove processing characteristics required for robust optimum design of bearings.

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We have been investigating a way to help English beginners improve their pronunciation by improving their understanding of the relationship between pronunciation and mouth movement. We analyzed the relationship between tongue movement and different combinations in English articulation. The result showed that there is certain relationship between them. Next, we analyzed movements of tongue and summarized them into several patterns. Then, we focused on the possibility of a specific arrangement of SMA actuators that can mimic the tongue movement during English articulation. This paper discusses SMA springs as soft actuators are very light and flexible, which can be suitable materials for mimicking tongue movement.

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This paper addresses the wall climbing mechanism by sucker-type adsorption for multi-copters. The mechanism is composed of bellows and suckers with an air compressor. The air compressor can be realized by the rotation force of the propellers. The wall climbing motion with controlling the air pressure is proposed. Finally, the motion of straight is verified by some experiments on flat and slop conditions.

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This paper presents a plan of wind power generation by a captive unmanned balloon with some feasibility experiments for increasing power generation on land. It can be expected that the increasing power device is effective though the result is in a proto-system on land. In the future, more experiments of wind power generation by a small captive unmanned balloon will be necessary.

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While the proposed single probe gripper shows promise in picking up an object using strong capillary and surface tension forces, the main challenge has been the smooth release of the object. I'm proposing to Study on micromanipulation using EWOD. By controlling the electrical field imposed on the gripper surface, one can manipulate the contact angle of the liquid bridge and therefore, the meniscus geometry. Modifyin g the curvature of the meniscus geometry causes the lifting force between the object and the gripper to change. In order to explain the grasping of the object by the effect of the contact angle manipulation, I conducted an experiment in units of mm. As a result, it was possible to separate by the self-weight of the object and the wettability of the surface by operating the contact angle by application of EWOD.

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This paper presents droplet transportation and droplet generation experiments using EWOD (Electro wetting on dielectric). EWOD is a technology for manipulating droplets discretely by controlling the electrical wettability of surface.1.5 μL ~5 μL of pure water droplets were successfully transported using transport device with an electrode size of 1.5 [mm] x 0.3 [mm]. During the generation experiments, droplet size varied from 2.5 μL to 4 μL were easier to generate. And it is verified that the minimum voltage of generation is 70V. By changing the program and the shape of the electrode, it is expected that a successful droplet generation can be achieved.

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Changing the uneven surface allow the water repellency to increase and decrease. The leaf of the lotus is known to form the water-repellent surface by a surface uneven and characteristic. In reference to it, I made the surface which changed surface height, the width of the column, a diameter. I made the water-repellent surface by applying water-repellent medicine to the uneven surface which I made. I drop a water on the surface which I made and observe the water-repellent increase and decrease by measuring a contact angle and a Sliding angle. Based on that we make a surface for transporting water drops.

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This paper describes adhesive characteristics of foot pads for insect-inspired wall-climbing robots. Ants can walk on the smooth vertical surfaces using an adhesive organ and secreted viscous liquid. We fabricated three kinds of adhesive pads inspired by the adhesive organ of ants, a glass pad, a PDMS pad and a glass pad with a water supply mechanism. Pure water were provided to the pads, and normal and tangential adhesive forces between the pad and a glass surface were measured. The experimental results show that the hydrophilization treated glass pad generates higher adhesive force than the untreated pad, and the pad with water supply mechanism generates long-lasting adhesive force.

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When the 3D printed structures were printed utilizing FDM 3D printer the layer grooves were generated on the structures. The layer grooves make the 3D printed structures strength decrease. Therefore authors already devised the 3D-CMF (Chemical Melting Finishing). The 3D-CMF is the method that dissolve the convex part of the layer grooves and filled in the concave part of the layer grooves and smoothen the layer grooves.3D-CMF reduces the cause of breaking of the 3D printed structures, which is considered to increase the strength. In this paper, we investigated the fundamental characteristics of the 3D-CMF and demonstrate of the change of the strength of the 3D printed structures.

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This study presents a novel optical method for visualizing adsorption process between contacting two surfaces using surface plasmon resonance (SPR) with the Otto configuration. The SPR microscopy developed in this study employs a point contact between a cupper hemisphere and an optically transparent glass prism. As a lubricant, hexadecane with Stearic acid of 0.01wt% was used. From some experiments, it was found that the SPR microscopy with a variable wavelength light source can measure reflectance spectrum easily as a two dimensional picture.

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3D bio printing technology was promised to fabricate complex cellular tissues. By printing cells or biomaterials for scaffolds, 3D cellular tissues are fabricated. Required printing precision are several tens of micrometer order, because cell size is several tens of micrometer. But, high precision printing is difficult, because almost biomaterials are high viscosity. Therefore, the 3D bio printer which is able to print biomaterials with high precision is needed for biofabrication. In this paper, we were developed micro bio 3D printer. This printer is able to print high viscosity biomaterials with high precision. In addition, to solve a problem that printed ink was spread on the printing medium, we used gelatin gels for printing medium, because gelatin gel was low wettability. Printed ink was sodium alginate and gelatin solution. This ink was able to be gelatinized with keeping print shape. By utilizing this device and these materials, we are achieved high precision printing of biomaterials.

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The crowd behavior recognition system is a subsystem of a distributed cooperative dynamic evacuation guidance system, and it detects and predicts crowd flow and abnormality occurrence by using machine learning method such as deep learning with visual and depth information obtained by RGB-D camera. The distributed cooperative dynamic evacuation guidance system aims to suggest evacuation routes at extensive evacuation situations by autonomously cooperation among plural sensors and evacuation guiding devices. In this paper, a recognition method of overall behavior of the crowd is proposed. Some indices for indicating the situation are examined in order to recognize the overall behavior of the crowd flow and the abnormality occurrence, and cooperate among the system by sharing the recognition results rapidly.

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In recent years, studies and applications of virtual reality (VR) have been actively conducted. Many of the studies on force sense presentation of VR sports are large-scale devices, and reproduction of shock is not strictly performed. In this paper, we focus on sense presentation of tennis and propose miniaturization of devices and waveform reproduction by genetic algorithm. In order to generate an impact on the racket, we mount a push solenoid in the racket, thereby making the force sense presentation device smaller. Moreover, by using genetic algorithm, we optimize the pushing timing of the push solenoid and reproduce the shock waveform. As a result, it was confirmed that the generated waveform approximates the impact waveform when the tennis ball was dropped into t he racket.

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In recent years, various techniques, such as Neural Network, Deep Learning and Genetic Programming(GP), to realize the adaptive behavior of the robot have been proposed. This paper aims to construct the control structure of the robot moving in the real world to realize the adaptive behavior through Evolutionary Hardware approach. The proposal method mentioned in this paper tries to build a gate network consisted of NAND gates by using Cellular Automaton and the adequate rule set of the Cellular Automaton is obtained by Genetic Algorithm(GA). And it is applied to the position control problem of the two-linked manipulator to confirm the effectiveness.

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In recent years, studies on posture analysis have been actively conducted in order to solve health problems related to posture. In this paper, we propose a net-type pressure sensor array using wires. The pressure distribution is estimated by the wire tension with pulleys and force sensors. By adopting a matrix-like structure, it is possible to configure with fewer sensors than the resolution of the pressure distribution. Furthermore, the “Center Of Pressure: COP” position, which is closely related to the posture, can be estimated by measuring each wire matrix. In this paper, the estimation accuracy of COP is verified by experiments and the estimation accuracy is improved by using Gaussian filter.

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