We developed a method for calculating the displacement of the beam spot focused on an optical disc by the objective lens for optical pickups. This method is reasonably accurate at predicting the stability in tracking servo control systems. The vibration model of an optical pickup is expressed as the frequency response function of the ratio of the displacement of the beam spot focused on an optical disc by the objective lens to the voltage applied to the tracking coils. The displacement of the beam spot was obtained by adding the product of the focal length of the objective lens and the incident angle of the beam onto the objective lens caused by mirror rotation to the displacement of the objective lens. The calculated values agree well with the measured results. Stiffening the pickup case around the mirror could help to decrease the displacement of the beam spot on an optical disc by 40%.

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This paper proposes a vibration control method of PC case. Vibration of the PC influences its performance. Especially, the vibration caused in hard disk drive (HDD) degrades the positioning control accuracy. From this background, this paper introduces smart structures technology to the PC case, and attempts active control to suppress the vibration of the PC case. In this paper, vibration test is carried out to measure the vibration characteristics of the PC case. From the measured data, the location of the actuator is determined, and control system is constructed. To achieve high control performance, this paper designs two controllers with different design conditions and their control performances are compared.

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Estimation method based on multibody system modeling for Frequency Response Function (FRF) of a driving unit in a printer was developed. The multibody system consists of combination of many masses, fundamental springs and dumpers. Using multibody system modeling with fundamental elements, there are mainly two benefits for estimating FRF. One is that calculation is easy and the other is that modeling is easy especially input/output interface of the model. To verify the developed method, a trial estimation of FRF of an intermediate transfer belt unit in a printer was conducted. For modeling the unit, belt rollers were replaced with mass elements and the belt was replaced with spring element respectively. The trial indicate that the estimated FRF was closely match with experimental result.

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For color electrophotographic printers, it is necessary to transcribe the color toner images stably and accurately from an intermediate transfer belt to the media. The production printer is required the image transfer accuracy that is higher than that of the office printer. Then, the production printer needs to adapt many kind of media. Error of the transfer system is varied by the media. This paper reports on the hardware configuration, control method and experimental results of the position control of the media feed direction for high-speed electrophotographic printers.

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The heads of HDD must be controlled at the center of each track within an allowable tracking-error-bound to read and write data safely. Thus, track-seeking process should finish only when the heads completely converge to the bound. Although the heads eventually converge to the bound after sufficient time because of the stable dynamics, it is important for the reduction of the access time to judge the end of the track-seeking as early as possible. In this paper, we propose a new method to determine the end of track seeking by using the maximal output admissible set considering an inter-sampling response. The effectiveness of the proposed method is shown by simulations.

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To improve positioning accuracy in a head-positioning control system for hard disk drives, we have developed a triple-stage-actuator system on a spin-stand tester. In this system, the first stage is a VCM actuator for moving a head-stack assembly, the second stage is a PZT actuator for moving a suspension, and the third stage is a thermal actuator for moving read/write elements. The frequency response of the thermal actuator showed that the thermal actuator system has no mechanical resonant mode. Therefore, this head-positioning system with a thermal actuator can control the head position in high frequency range without negative impact from mechanical resonances. As a result, the servo bandwidth of the proposed triple-stage-actuator system can be higher than that of the conventional dual-stage-actuator system which consists of the VCM and the PZT actuators. This improvement is similar to the improvement from the single-stage -actuator system to the dual-stage-actuator system. Experimental results on the spin-stand tester showed that the proposed control system can dramatically improve the positioning accuracy during a track-following control.

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Plastic films which are transported by many rollers are wound up in the roll. This winding method is called the roll-to-roll system. This production system which is performed a large number of processes makes it possible to low-cost and mass production. However, when the web is wound up in the roll, surface asperity of the wound roll occurs by thickness variation of the web. We need an accurate measurement of internal stress in the roll for winding up many webs without occurring surface asperity of the roll. However, the research on internal stress state in wound roll considering the thickness variation in width direction of the web has not yet been carried out. In this study, we fabricated a multipoint sensor to measurement the radial stress distribution in axial direction. As a result, we succeeded in fabrication of the sensor that can be measured it.

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Plastic film is produced by Roll-to-Roll system. In this system, winding process is the final section of the producing line, which influences the quality of film. Therefore, winding process is very important. However, the film thickness distribution becomes larger by film-firming processes, printed electronics and laminating processes in this system. As a result, film thickness is not uniform in the width direction and it leads to gauge band in the wound roll. In this case, internal stress changes in the width direction. In addition, the film thickness distribution is changed by the elastic deformation. Therefore, it is necessary to understand the internal stress to prevent roll defect in wound roll. In this study, a winding model considering the film thickness variation and the elastic deformation is presented and experimentally verified. As a result, the predicted values are in good agreement with the measured values.

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Thin and flexible continuous mediums such as plastic films and thin metal films are called the web and that is used to make a high functional device. In recently, the web products have especially attracting attention on lithium secondary battery which is made from the web. Therefore the Roll to Roll process has been tried to fuse to technology of printed electronics for mass produce the web products. However, that challenge has not successful yet because a web defect which is called wrinkles and film meandering are often occurred in process of transporting in Roll to Roll. The web is been transporting by physical contact with many rotating roller and those defect are caused by variation of friction force acting between the web and the roller. In general, it is known to the effect of the humidity on friction characteristic from previous research and we have confirmed that condition of surrounding atmosphere affect to friction force. But it had not considered the effectiveness of the roller surface roughness that has generated a strong effect on contact of friction. Consequently, in this study, we tried to clarify the effect of change in the roller surface roughness and humidity on static friction characteristics between plastic film and steel roller

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In recent years, flexible devices have attracted attention. These devices are produced by Printed Electronics. However, it is difficult to mass-produce those devices by Printed Electronics. Therefore, Printed Electronics is expected fusing with Roll-to-Roll. The combining process is called Roll-to-Roll-Printed-Electronics which is expected to mass-produce of flexible devices. However, the large quantity of air is caught up in between the film and the steel roller under low tension and high speed transporting. Consequently, the film is floated, and then slippage are occurred because condition between the film and the steel roller is changed. Therefore, we need to investigate friction properties between the film and the steel roller changing conditions of transportation. We carried out experimental examination of kinetic friction properties of between the film and the steel roller to change tension, thickness and velocity. As a result of this experiment, kinetic friction coefficient decrease with decrease in thickness.

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This paper introduces a method of upstream product design for low-noise MFP (Multifunctional Peripherals). At first, noise level of similar MFP is measured and the acoustic power level of each noise source is calculated. If motors of new MFP differ, single noise source data is acquired separately. Non-stationary noise such as paper collision noise and clutch, are extracted by subtracting stationary noise (ex. motor) from copying noise applying spectral subtraction. Acoustic power levels are predicted according to specifications such as noise level and copying speed and the contributing rate of noise sources are calculated. Next, the level of noise sources are assigned according to the size of the contributing rate and the difficulty level of noise control so that a new MFP noise level will fit in the specifications. The rank order of noise sources with high contributing rate was properly extracted.

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Rubbing noise of a paper with guides in paper-handling mechanism is getting louder now with the higher sheet feeding speed in printer or copy machine. This research deals with the paper vibration caused by sliding contact with guides. The purpose of this research is establishing a theory of rubbing noise. First, it was found that the characteristics of rubbing noise depend on state of the contact of paper and guide. Next, the influence of distance and angle from the guide of roller on rubbing noise was revealed. Finally, it was shown that volume of rubbing noise was affected by degree of inclination of guide.

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It is important to understand behavior of ink penetration into paper for designing inkjet process which enable both high speed and high quality of print. However, there was no method to visualize the phenomena directly. In this study, to visual ize ink penet ration, the de vice based on optical coherence to mography has bee n developed. Optical coherence tomography is the technology acquiring cross-sectional images of objects in non-destructive observation. Ink penetration process has been observed as the time-va rying cross-sectional images of paper through the use of this device. In addition, quantitative evaluation of penetration around ink and paper has become available as displacement of boundary surface of penetration in cross-sectional images.

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Some kind of inkjet printers use water-based ink and it is known that the moisture contained in the ink causes paper curl. Especially high-density image printing, the paper becomes excessively curled and large paper curl lead to messy paper stack on the paper tray and it prone to smearing that may be caused the tip of the curled paper touched inkjet head. On the other hand, it is also known that the paper curl decreases when a curled paper is held in the paper path. However, a prediction method for these phenomena, which is appropriate for the efficient development of products, has not been developed. In this paper, we proposed a prediction method of curvature in such paper curl phenomena. The proposed method includes some mathematical models of paper that are the extension and the stress relaxation of the paper after ink printing. Whole coefficient related these mathematical models are decided experimentally. Then, the calculation of curvature after ink printing is carried out. The proposed prediction method is verified experimentally and the results indicate that it provides appropriate precision for paper curl of an inkjet printer with water-based ink.

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At second transfer roller process in electrophotography system, paper deformation is caused by electrostatic force stronger than the rigidity of a paper, which might cause paper jam. We are studying to understand the mechanism of paper deformation by charge generated on a paper. So a numerical simulation tool is developed in order to analyze the paper deformation by the effect of transfer parameter. And also we observe paper deformation occurred by electrostatic force. The calculation results are compared with experimental results. The calculated tendency to paper deformation results shows good agreement with the experimental results.

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Several kinds of wound roll defects like telescoping, dishing, starring, and wrinkles often appear in many manufacturing lines of web handling companies. In order to investigate how the dishing or telescoping is developed, three web winding processes are simulated by using a three dimensional FEM model which is composed of an isotropic web and a rigid core. The results show that (1) the web is wound around the core executing a slow vibratory motion in the lateral direction when the core is inclined against the web or winding tensions of both sides of the web are different. (2) The telescoping suddenly occurs when a lateral distributed load acting on a normally wound roll increases gradually. The critical lateral load gets larger as a winding tension or friction coefficient increases.

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We developed behavior modeling method of bill in non-pinched belt conveyors at high speed. Non-pinching belt conveyors are commonly used in bill sensing system since flapping of bills degrades the performance of sensing. However, predicting the complex behaviors of bills in these conveyors at high speed is especially difficult because of the thin thickness and low stiffness. To improve the prediction accuracy, here we introduce probability model and Bayesian inference into analysis model. The proposed model is evaluated by comparing with experimental data obtained with laser displacement meter, and the prediction accuracy of the model is 98.4%.

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The dragonfly wing is passively deformed under flapping and has the strength to withstand high flapping frequency simultaneously. These characteristics of vibration of wings are important for dragonfly flight. However, the effect of those on dragonfly flight has not been well understood. For the purpose of investigating an artificial wing suitable for flapping Micro Air Vehicle, we measured natural frequency and deformation of the wing and fabricated the artificial wing based on the results of that. From the results, the dragon fly wing has the high natural frequency of 120 Hz. The tip-side of the wing is greatly deformed. Then, we fabricated the deformable artificial wing which can deform in the same manner of dragonfly wings and measured aerodynamic force and power consumption under flapping. As a result, the power efficiency of aerodynamic force using the deformable wing is 5 times greater than the power efficiency using an undeformable wing.

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Recently, there are many researches related to single cell trapping techniques using a microfluidic device. We have proposed a cell trapping array having micro-channels, micro-orifices, and tapered structure for single cell analysis fabricated by multidirectional photolithography and soft-micromachining. In this study, we investigated agglutination of cell samples infused to the cell trapping array to improve cell trapping efficiency at each orifice.

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For gene analysis in clinical diagnosis, we have demonstrated extension of chromosomes by flow induced by a centrifugal force and compartmentalize them at the microfabricated 3 dimensional mesh array. In this study, we analyzed flow field generated by the centrifugal force by finite element method. Then, we evaluated the correlation of the experimental and numerical results. The drag force in the fluid mainly extends the chromosomes on the microchip.

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This paper discusses the efficiency of an electrostatic vibration power generator made from silicon MEMS technology. From the consideration of an equivalent circuit of the vibration device having built-in voltage, the relation of the efficiency and force factor of the device is described. The relation between quality factor and angular frequency is also discussed in terms of generating power and vibration energy of the device

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We report the first step to build a mobile, low-power MEMS (Micro Electro Mechanical Systems) switch using two comb-drive actuators with a movable component. Sidewalls of the comb-drive fingers were covered with potassium ions doped electret films. As a result, a built-in electric field of 75 MV/m was generated between the opposing faces of the combs. These actuators are mechanically combined to a push-pull component to change the position between two mechanical states. Switching from one state to the other required only a voltage pulse (with an energy of 36 nJ) and thus, bistable actuation was achieved with low-power consumption.

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The actuators using electrostatic energy have been reported because these actuators have some advantages. It can be driven by a little energy because of using electrostatic energy. These actuators also have simple structure and it is easy to miniaturize them. However, these actuators generally can generate low power. The reason is that the energy conversion method from electrostatic energy to mechanical energy is not appropriate. We proposed the novel drive principle of the microactuator, which makes electrostatic energy/force collaborate with the elastic energy/force. In this paper, this microactuator powered by collaboration of electrostatic and elastic energies/forces was fabricated with solving some problems on the fabrication process. The operation of the microactuator was observed by applying voltage of 150V.

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Dual-axis friction force microscopy probe can provide accurate measurement of lateral and normal forces without mechanical interferences of lateral and normal deformation of the probe. However, lateral movement of the probe causes essential problems such as image distortion and degradation of lateral resolution, which come from position difference between the tip and probe support. Here, we tried to solve these problems by using a dual-axis probe with an electrostatic actuator and controlling the tip position by the electrostatic force.

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In this study, we fabricated the triaxial force sensors embedded in the shoe insole, and measured the relationships between planter stress and heel height. The size of the micro triaxial force sensors and the prototype triaxial force sensors were 15×15×4.5 mm^3 and 25×25×10 mm^3, respectively. The sensitivities of Z, X, and Y axis force sensor were 0.299 kPa/mV, 0.060 kPa/mV, and 0.063 kPa/mV, respectively. We measured the triaxial force of forefoot and heel on the condition of heel height from 0 to 90 mm. We confirmed that the pressure of the middle part of forefoot and share stress of outside part of forefoot were increase with heel height.

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In brain science and psychology, one of the most important purposes of recent studies about neural network, biological circuit in brain, is to establish a method of treatment for the central nervous system disease, such as Alzheimer. "Optogenetics" is a new technique for analyzing neural network. In optogenetics, neurons in a neural network is stimulated and controlled by visible lights. In this paper, we propose an integrated microchip having micro electrodes and micro lenses. The proposed microchip stimulates a brain slice sample with two focused lights which have different affection to the neuron, and measures the electrical reaction of the neural network.

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Generally, chrome thin film is used for shading material of a photo mask. Pattern precision of the chrome mask is unstable in chrome wet etching, and process cost and environmental risk increase in chrome dry etching using chlorine gas. In this study, we investigate dry etching method using non-chlorine gas for the Cr mask patterning. Etch selectively between Cr thin film and protective resist treated by vacuum UV cure method were measured in electron cyclotron resonance plasma etching using Ar gas as inert gas.

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In femoral fracture reduction, it is required for the orthopedic surgeons to pull distal bone fragments with large traction force and return it in correct position referring 2D-CT imaging. Since these method had been burdened with them, it is effective to introduce robot assist. The robot had been developed, but the control method is not established yet because of lack of experiment data. The reason of lack of experiment data is we cannot carry out the experiment because the cadavers or animals are different from living body in muscle characteristic or anatomically. So the experimental model that simulated human femoral characteristic is needed. In this research, human muscles can be reproduced by using Mckibben type pneumatic rubber actuator (artificial muscle), and developed the model that simulated typical femur muscle with artificial muscle.

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