Nanometer scale device in the thickness direction has already been realized in the industry. Next step to be studied is spatial control and usage of nanometer scale structure. Including the process for its development, requested of the Nano-device and its application system is an aspect of building a base for constructing the sustainably evolving society, for example, from a viewpoint of minimizing environmental burden. Such a purpose cannot be accomplished when merely the conventional development road map of the existing technologies is pursued. Nanotechnology is roughly divided into two fields. One is the field where we can find living examples or hints for new idea abundantly concealed in the living things and/or ecological system, while the other field is the frontier to be newly developed. Covering the fields in full detail is yet vague, since the systematization of Nanotechnology is still immature and the technology fields themselves are on the way of being rapidly developed and expanded. This lecture is intended to offer a hint for considering how to build competing domination at stages ranging from "Science" to "Industry," and is also focused on the importance of destructive innovation and roadmap of united technologies.

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Paper feeding problems find technical applications in numerous information equipments. For example, copy machine, printer, automatic teller machine and etc.. This paper deals with the features of paper feeding as a form of frictional drives and the two schemes in finite element analysis of paper transport velocity with a pair of a rubber-covered roller and a rigid roller.; One is an incremental theory explaining transitional behaviors of frictional drive from slipping between a rubber covered roller and a paper to stationary tractive rolling step by step of revolution.. The other is a direct solution using by the Galilean transform converting the governing equations of motion to a spatially dependent form, which is applicable to viscoelastic and inertial effects.

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This report describes the theoretical modeling of friction coefficient between uncoated paper-web (newsprint; for example) and steel roller. In the modeling, the paper base is approximated by the linear spacing and the surface asperities are treated as rigid body. Introducing the contact mechanics and assuming the Gaussian distribution of surface asperities, the mixed friction coefficient is formulated theoretically for a wide range of roller surface velocity, in which the air film thickness between the web and roller is estimated based on the foil bearing model. A comparison between the predicted results and the experimental results is presented to verify the applicability of the model.

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Printers and copiers have to feed papers one by one by using rubber rollers. How to design paper feed mechanism is a serious problem in developing these machines. The present article gives some simple ideas to designers concerning how to estimate a paper feed velocity when a friction between the rollers and paper is given, even though the rubber roller stiffness is not taken into account.

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As examples of recent research on the head/disk interface (HDI), the following topics are introduced: (i) analyses of dynamics of flying head considering van der Waals force (one degree-of-freedom (1-DOF) model, 2-DOF model, and two dimensional pressure distribution), (ii) analyses of flying characterstics of head slider considering liquid (lubricant) surface deformation, and (iii) dynamics of liquid meniscus bridge.

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Dynamic characteristics of a magnetic head slider of a hard disk drive were analysed using 2 degrees-of-freedom (2-DOF) mechanical model considering the dynamic pressures due to the van der Waals force and the air bearing force. The corrected van der Waals force equation for multilayers and the molecular gas-film lubrication (MGL) equation were used to calculate the pressures. It was found that the signs of the total stiffness of the mechanical system could be reversed due to the negative van der Waals stiffness when the spacing became small. The spacing at which the total stiffness was zero was defined as the "stiffness reversal spacing", and the characteristics of the stiffness reversal spacing was clarified. The animations of the slider motion were shown in order to see the influence of the van der Waals force.

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We calculated the characteristics of contact force and adhesive force between contact pad and disk surface considering asperity contact, attractive force of the lubricant and bulk deformation. At first, we compared the results of GW model and our present model. As a result, we found that the bulk deformation becomes predominant when the asperity density is large and the rms value of asperity peak height is small as in cases of current slider and disk surfaces. Nest, we examined the intermolecular adhesive force and the contact stiffness as a function of asperity contact pad area, density, rms value of the peak height, asperity radius of curvature and lubricant thickness. As a result, it was found that the rough surface can be modeled by a simple bulk contact force and attractive force can be modeled as constant attractive force when the asperity density is large and the rms value of asperity peak height is small.

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This paper deals with experimental study of elastic force, damping force and adhesive force in dynamic collision of a spherical slider with a magnetic disk. We used an Al_2O_3TiC and glass spherical slider with a radius of 1mm and magnetic disks whose substrate is Aluminum (Al) and glass. The Al disk samples have four different lubricant film thicknesses of 0, 1, 2, and 3 nm. We found that the static pull-off force of glass slider is close to 4πRγ where R is radius of the spherical slider and y is surface energy of the lubricant. The dynamic adhesion force is larger than the static pull-off force but not far from 4πRγ except for the case of 3 nm lubricant thickness. The adhesion force at 3 nm lubricant thickness significantly increases probably because of squeeze damping force. Contact stiffness of rough Al_2O_3TiC slider is much smaller than Hertzian contact force, whereas that of smooth glass slider is higher than the Herzian contact force.

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The report is about a simulation of a negative pressure slider due to a shock. In the simulation, a shock with downward direction and a shock with upward direction are used. The shock is set as a triangle wave with maximum value 9800m/s^2(1000G) and varied duration. It is clear that squeeze effect of air bearing surface play an important role when a shock is gave to slider. In the case under downward shock, the flying height variation in short duration is smaller than in long duration, and in the case under upward shock, the suction face in short duration is larger than in long duration.The suction force of ABS under a upward shock is larger than the suction force that occurs in normal flying situation.

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This paper describes the interactions between flying head sliders and ultra-thin liquid lubricant films. The dynamics of sliders was monitored using Laser Doppler Vibrometer (LDV) and Acoustic Emission (AE). The slider hysteresis behavior of touch-down and take-off processes was investigated as a function of the disk velocity. As a result, it is found that the difference between touch-down velocity and take-off velocity of A20H lubricant films were larger than that of Zdol, and the LDV RMS signals for A20H lubricant films became larger than that for Zdol. In addition, the replenishment characteristics of two kinds of ultra-thin liquid lubricant films was studied and discussed.

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Vibration transfer characteristics through a liquid meniscus bridge were investigated experimentally using the meniscus response apparatus. Effects of the excitation amplitude and the contact angle on the vibration transfer characteristics were clarified. The large contact angle was obtained by applying oil repellent to a glass plate. It was found that the excitation amplitude affected the vibration transfer characteristics and the contact angle amazingly affected them because the boundary condition at the meniscus periphery was changed.

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The dynamic force between solid surfaces linked by a liquid meniscus bridge was analyzed assuming small vibration of the spacing newly. Combined model considering change of contact angle and boundary position was constructed as an analytical model. The incompressible.' Reynolds equation was solved under the Laplace pressure boundary condition and the solution was linearized by the small vibration assumption. Applying the spring constant and damping coefficient of a meniscus derived from the analyses to a mechanical system, the vibration transfer characteristics through a liquid meniscus bridge are analytically clarified and compared with the experimental results. Combination coefficient is derived from comparison between experimental results and theoretical results. Velocity of solid surface increases, then amplitude ratio approachs variable boundary position model.

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Low-coherence phase-shifting interferometry is presented for measuring spreading of a molecularly thin lubricant film. This method provides lubricant distribution in three dimensions from calculation using phase-shifted two-dimensional interferograms. As light source, low-coherence white light was employed, demonstrating a remarkable effect on suppressing image noise as compared with a laser. The phase-shifting function was realized by attaching a high-precision piezo actuator to the reference surface of the interferometer. To prevent fringe drift induced by mechanical vibration, the signal of fringe position detected by a position sensitive detector was used for feedback control of the piezo actuator. By accurately driving the position sensitive detector, high-precision phase shift was realized even in the presence of vibration. The applicability of the low-coherence phase-shifting interferometry was confirmed by measuring a nanometer-order-thick lubricant film on a diamond-like carbon surface.

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Depletion and replenishment characteristics of molecularly thin PFPE lubricant film coated over magnetic disk were studied through the pin-on-disk sliding test using magnetic disks coated with hydrogenated diamond-like carbon and a semi-sphere glass pin. Depletion and a pile of the lubricant after the sliding test and recovery process towards original flat surface were measured using OSA (optical surface analyzer). A peculiar phenomenon was observed wherein the replenishment function of lubricant was stalled or weakened when the residual film thickness after depletion nearly equaled to a monolayer of PFPE molecules. This phenomenon can be attributed to the fact that the polar component of surface energy takes a local minimum just at a film thickness equivalent to a monolayer of polar molecules.

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In this paper, we propose a new head positioning mechanism of a magnetic disk storage. On the basis of the concept of the in-phase positioning mechanism, a new positioning mechanism is designed for 2.5 inch single disk and single side recording drive. Natural frequency of it's primaly resonance mode is about 8.5kHz. This positioning mechanism is actuated by a voice coil motor attached on the middle of the arm, which is more reliable device than other positioners with micro-actuator. To show the performance of this positioning mechanism, we design a Η_∞ controller for this positioner. Under assumption of continuous time control, the band-width of this positioning system is over 3kHz which can achieve 200kTPI track density.

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This research shows the new design concept of an actuator in hard disk drives. The actuator which has several higher-order mechanical resonance determines the stability and mechanical noise suppression ability of the servo control system. We presented the new design concept that higher resonance are made in-phase to the first major resonance. In this concept, all the resonance with high gain are in-phase but the outphase resonance's gain are reduced. This mechanical characteristic can be achieved by the carriage arm shape design which pay its attention to 1st and 2nd arm sway mode. In the actuator based on this concept, the higher resonance can be compensated only by the compensator which is designed for the first major resonance.

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A conventional spin-stand system which used to evaluate read-write performance of magnetic recording heads and media can not allow thermal drift of its mechanism and run out of its air spindle motor. Therefore, we propose a precise tracking actuator for the spin-stand system like a piggyback actuator. The actuator constructed with a piezoelectric element(PZT) and a stroke amplifying mechanism. We applied a robust controller using Η_∞ control theory for the tracking actuator, The designed system showed good controllability guaranteeing the control performance for two kinds of HGA(Head Gimbals Assembly) fixture (0.2g fixture and 2.0g fixture).

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In the head positioning control design of hard disk drives (HDDs), holder has less limitation on its running frequency than sampler. Thus, so-called input multi-rate control has been widely used in order to improve the performance, and many algorithms have been proposed so far. However, all the methods assume zero order hold (ZOH) as a hold function although the hold function does not necessarily have to be ZOH. In this sense, the designed method with the use of the Generalized Hold Function (GHF) is quite attractive since it does not assume any conventional kind of hold function but yields a piecewise continuous function with jumps at measurement instance. In this paper, we studied the possible performance enhancement for track-following control of HDDs that can be attained with a GHF by conducting several simulations. Our results show that we can have some advantage in terms of the position accuracy in standard deviation compared to the conventional Η_∞-based controller.

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This paper describes dynamic analysis of a dual-slider type active head slider with a piezoelectric actuator for flying height. Tracking ability of the slider and the head to normal vibration and microwaviness of the disk surface has been investigated using a three-degree-of-freedom slider model and the MGL(molecular gas film lubrication) theory. It is found that the air-bearing pad below the head generating negative pressure is superior to the one generating positive pressure to improve the tracking ability.

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This paper describes a novel active head slider equipped with micro-actuator using PZT thin films for flying height control. The active head slider is a breakthrough technology for achieving ultra-low spacing of less than 10nm. The position of a read/write magnetic head is gone above and below because an unimorph cantilever build in the slider bends by PZT thin film, and flying height is controlled. The multi-step silicone etching process by ICP-RIE or RIE is important to fabricate active head sliders. Therefore, the fabrication process of a silicone slider structure was completed by optimizing etching conditions.

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Recently, it is important to clarify air flow induced vibration issues for hard disk drives in order to achieve ultra-high magnetic recording density. We studied flow induced flutter vibration of co-rotating two disks by using LDV. We also measured pressure distribution between two disks using a pressure sensor. From the experimental results, we found that the arm which is inserted between two disks suppresses the disk flutter vibration. In addition, it is found that the mean pressure increases and its fluctuation decreases, when the arm is inserted between two disks. Therefore, it is suggested that there is the correlation between the disk flutter vibration and the pressure fluctuation between two disks, and the disk.flutter can be suppressed by inserting the arm or spoiler that decreases the pressure fluctuation between two disks.

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We proposed a simple disk spindle assembly supported by a full cylindrical fluid journal bearing at the top of shaft and a spherical grooved pivot bearing at the bottom of shaft and made clear that the gyro effect can make this spindle stable. In this study we manufactured three prototypes of the disk spindle composed of two 3.5 inch disk platters, a full cylindrical journal fluid bearing and a spherical grooved pivot bearing. Then we measured radial vibration and axial vibration at rotational speed up to 9150 rpm. We found that the amplitude of half frequency whirl is about 30nm. We also evaluated the NRRO and bearing stiffness to unbalance force.

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In the development of hard disk drives (HDD), the head position control is very important issue and it is influenced by the flow of the disc rotation. The analysis of that flow has many difficult problems such as the modeling and the computing time. Then, this report shows unsteady analysis of HDD internal flow using the Lattice Boltzmann Method.

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We propose the negative pressure type flexible optical head slider as an air-bearing slider by fluid lubrication, which is one of the factor technologies of near-field optical recording that is new signal regeneration technology beyond diffraction limit. We established the design method and evaluated the performance by simulation. To be concrete, ±50μm slider tracking performance for the outside displacement of the disk and adjustment capacity of lm curvature radius of a warp in a slider were ascertained.

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In the advanced information technology, a large amount of data should be handled and it is necessary to develop ultra-high density data storage devices. So far, many innovative technologies have been proposed in order to increase the recording density of optical disk storage devices. Multilayer optical disk is one of the high-density technologies. This technology, however, has serious technological issues related to arise aberration for multilayered disk media. This paper proposes MEMS-Based aberration free mirror micro actuators using PZT thin film. In this paper, the fundamental design of the proposed MEMS-based micro mirror actuator mechanism is studied and the fabrication process of the mirror actuator is developed.

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Two kinds of actuator structure for optical disc drives reducing the rolling moment in the track coils were developed. One of the structures is an arrangement in which the track coils and magnets are crossed. That is, track coils on one side of the actuator are arranged inside the magnets, and those on the other side are arranged outside the magnets. The other structure uses two-pole magnets in opposition to the track coils. These two structures can cancel the vertical forces generated in the track coils, thus reduce the rolling moment. The experimental results show that the inclinations of the developed actuators at the resonance point in rolling mode were reduced to 60% and 20%, respectively, of the value for a conventional structure.

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New technologies of sensors and mechatronics are now applied positively for surgical intervention. In this paper, recent developments of the high performance surgery with mechatronics are introduced including surgical navigation system, chemical navigation with 5ALA, augmented reality image overlay device, surgical robots for remote surgery and MRI compatible robots to achieve minimally invasive surgery. Two examples of the image overlay system and the MRI compatible navigation robot are shown and the important factor of the development of surgical devices are discussed.

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This paper reports a study on the development of an artificial rectum valve. An artificial rectum valve is developed using an SMA plate as the actuator. At body temperature, the SMA plate takes an arc shape, and the valve closes the rectum by the force of a bias spring. When the SMA plate is heated by the electric current that flows through the nichrome wire to the plate, it recovers its original flat shape, and then opens the valve to enable the evacuations. The motion characteristic is studied from preliminary experiments, which confirms that the valve closes at the body temperature and opens when the SMA plate is heated. Furthermore, to verify the function of the artificial rectum valve as an anal sphincter, in vivo animal experiments were conducted using dogs. The experiments verify that this rectum valve works well as an artificial and sphincter.

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This paper is a study on the development of a sensor for measuring tactile sensation. The sensor using pyroelectric of a PVDF (Polyvinylidene Fluoride) film is assembled. The base of the sensor is an aluminum, around which a synthetic rubber layer overlaid with Nichrome wire, a PVDF film and a protective layer of acetate film are stacked in sequence. The sensor is heated and kept at a constant temperature by Nichrome wire and thermistor attached on the sensor through PID control. The heated sensor is contacted with the object to obtain output of pyroelectric effect from the PVDF film. Through experiments on different fabrics, the results show that the PVDF sensor using pyroelectric is 'available to obtain information on warm feeling.

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The purpose of this study is to establish a method of measuring precisely the seismocardiogram (SCG) of a patient who lying in an open magnetic resonance imaging (openMRI) machine for myocardial ischemia monitoring during surgery. Vibration isolation was examined by analyzing the gantry vibration during MRI scanning and the SCG of a healthy volunteer. The signal-to-noise ratio between the SCG and the patient bed vibration was calculated to be 6. These results demonstrate that the peak acceleration of the SCG can be monitored during openMRI scanning. In conclusion, vibration analysis showed the feasibility of using the piezoelectric acceleration sensor for seismocardiogram measurement in the openMRI-guided operating theater.

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Interventional MRI therapy has started in these years, and surgical robots operated under the MRI environment are Focused by many researchers to achieve most effective image guided therapy. In this paper, the MRI compatible modular designed navigation robot for needle screw insertion is proposed, and system feature is described. It comprises a feed screw, aluminum parts, FRTP parts and ultrasound motor, that are all non-ferromagnetic characteristics. Influences of the robot to MR image(image distortion) are reported.

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We have been developing exoskeleton robots to assist the motion of physically weak persons such as elderly persons or slightly disabled persons in daily life. In this paper, we propose an intelligent control method of an exoskeleton robot for human forearm motion assist. The robot automatically assists the forearm daily motion mainly based on the skin surface electromyogram (EMG) signals in the proposed method. Fuzzy-neuro control has been applied to realize the sophisticated real-time intelligent control. Experiment has been performed to evaluate the proposed method.

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This paper is concerned with the development of a wireless stethoscope system for diagnosis of cardiac disorders. This system consists of an electronic stethoscope, a sound converter circuit, audio wireless transmitter and receiver modules and a computer. The cardiac sound is easily acquired by the electronic stethoscope and transmit to computer by audio wireless modules for abnormal cardiac sound monitoring and diagnosis. A filter with the eardrum mechanical characteristic is designed and characteristic waveforms are obtained by applying the recorded heart sound signals through the filter. Some experimental examples have shown that the characteristic waveforms are powerful to diagnosis the abnormal heart sound and easy operation for the users who even have no special knowledge on the cardiac diagnosis.

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Elastic property is an important factor of skin touch through which we sense the condition of the skin. From the viewpoint of cosmetics and toiletries, stratum corneum is most important because it is the surface layer of the skin and is directly affected by the variety of environmental factors. In this study, we have measured the stiffness of the stratum corneum in vivo with a commercially available suction device (Cutometer) and in vitro with a uniaxial tensile tester. In the Cutometer measurement, the aspiration pressure was increased linearly with time to detect subtle deformation of the stratum corneum. Using these methods, we could detect the decrease in the stiffness following the application of glycerin both in vivo and in vitro. These results suggest that our measurement methods are useful when evaluating the feeling of skin touch affected by daily events.

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To make an automobile indoor winker sound more comfortably, firstly we carried out an auditory perception experiment using several winker sounds. Then FFT analysis and principal component analysis of the waveforms of winker sounds were done. Based on these analyses, we found that the growl sound deteriorates the winker sound. Finally, we build the prototype winker, and also got the good characteristics of the winker sound.

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In the present paper, we first derive a mathematical model for a spiral beam model micro manipulator for optical switches and then we show that this mathematical model simulates the device correctly by checking its results. We use this mathematical model for design of fabrication parameters of this micro manipulator. We will show that the designed micro manipulator for optical switches is capable of rotating the reflecting mirror by 32° with operating voltage of 163 volts. Also the state, of stress analysis of switch model shows that the generated stress in the structure (369 MPa) is well beneath the fracture strength (7000 MPa). We also suggest a control method for this optical switch using our mathematical model.

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In the area of the manufacturing of plane display and semiconductor, there is a problem that the micro particles which are adhered in the manufacturing process give bad influence to the yield of product. In recent years, a demand of removal of them has been becoming tight from a viewpoint of the yield. Namely, considering the adhesive force and an adhesion state of the material and so on, respectively, the development of new technology to pick them up is needed. In this paper, we present a manufacture technology of microgripper which grips the micro particles and experiment in removal of adhered particles by the developed microgripper. As a result, under the observation of an SEM, picking up micro particles of several micrometer diameter is succeeded by using the device which we developed.

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The geometry measurement method that changes a phase by a part of reflective mirror precise movement is proposed, and is applied for the phase difference microscope system. Using this principle, the variable phase-contrast microscope that can measure nano-micro meter size geometry at high speed and high precise is examined. For this purpose, a silicon mirror with height differences was fabricated and the optical system using the device with the piezo-electric actuator was configured. Using this system, the principle of the nano-micro meter size geometry measurement was confirmed.

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Over the past few decades, rapid strides have been made in high speed and high precision wire bonding, which is one of semi-conductor assembling processes. The high speed and precision are mainly realized by XY-table and bonding head of wire bonder. Especially XY-table requires low vibration after high speed positioning. This paper reports that our accomplishment in developing the low vibration AY-table, which consists of liner motor and has the structure of high natural frequency.

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This paper proposes a novel micro actuator head for ultra-high density hard disk devices. In order to improve of the recording density of the hard disk drive, tracking control technology that positions heads on the track with high speed and high reliability and head-disk spacing control technology are necessary. In this study, the microstructure that was able to be driven independently in both tracking directions of in-plate and out of-plate motion by the use of the PZT thin film was developed. This mechanism consists of high aspect-ratio parallel ribs and flat plate structure. This paper also reports a silicon micro machining technology and the PZT thin film deposition technology on the vertical sidewall of parallel ribs necessary.

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This paper describes the development of novel PZT thin films. The feature for novel PZT thin films is that double-layered composite PZT thin films which laminate sputtered PZT thin films and sol-gel PZT thin films. The novel PZT thin films are found to have the higher (111) preferred orientation than not only sol-gel PZT thin films but also sputtered PZT thin films. In addition, it is found that composite PZT thin films, which feature is that the sol-gel derived PZT thin films are deposited on the sputtered PZT thin films, shows better characteristics.

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An automatic electric power generator that utilizes self excited rotation has been investigated as a power supply for information devices. By the approximate analysis with the dynamic model and the numerical simulation, we confirmed the conditions when the self-exited rotation takes place. In order to create self excited rotation, we suggest a system that increases the angular speed. When revving up, the motor is used as an actuator rather than a generator. The experimental results show that generating capacity increases from 10μW to 380μW by the system. The input voltage and time was optimized to reduce energy loss. We propose a system that revs up the rotational plummet till self-excited rotation occurs in order to lessen the influence of the initial plummet position and angular speed.

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An automatic electric power generator that utilizes self-excited rotation by vibration has been investigated as a power supply for information devices. The amount of electric power of a rotated type generator increases by using self excited rotation. In the theoretical analysis about self excited rotation that generate under the limited condition, we deterimined the control method of self excited rotation and established the judgment method of the possibility that self-excited rotation stops in transition. states such as impedance control that uses change of an electric damper. And we manufactured parameter variable generator to show the validity of impedance control. As an example of the optimal design, we selected the coil core of the generator applying the established method.

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Recently, the power supplying devices for the ubiquitous in formation devices require miniaturization and low environmental load. As example of ubiquitous information devices, portable digital measurement instruments like digital tape measure and micrometer caliper are produced commercially. In this study, automatic power generating unit for the digital tape measure was developed. In the first phase, the feasibility study was done by making the macro-model and performance of the macro-model was evaluated to achieve guidelines of optimal design. In the second phase, the examination of the miniaturization and the evaluation of the performance of an automatic generating unit was examined by making the 2nd trial unit based on the optimum, design.

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In case that users exercise for healthcare, the users require the effect of exercise. Gait speed measurement is focused as the useful index of the effect by exercise. Gait speed is correlated with Energy consumption, and one of the most basic index. The object of this study is to construct the "Wearable Information Healthcare System". As the first step of this study, the algorithm of accurate and convenient analysis method of gait speed is developed. The new algorithm is evaluated in the field test, and the calculated value is agreed to the true value.

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