[in Japanese]

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Loverich et al. have reported a micropump by dielectric elastomer actuation (DEA). The micropump has been fabricated everything from polymer, and achieved highly efficient and low-cost. A microfluidic chip incorporating the DEA micropumps is designed and fabricated in this paper. Assuming an analytical system that should transport sequentially and independently three liquids, the micro fluidic chip was designed. The microfluidic chip consists of three DEA micropumps and check valves. Fabricated microfluidic system performed independent motion of DEA and fluid control. It is possible to transport fluids without mixing. Actual analysis using the chip is future works.

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Recently, many single-cell analysis systems have been proposed for electroporation and patch clamp. We have proposed a microchip fabricated by the SIngle-Mask inclined UV PhotoLithography for Embedded network (SIMPLE process). The microchip fabricated by SIMPLE process is made of thick negative photoresist SU-8. In this study, we carried out the toxicity and proliferative tests of SU-8 to living cells. Then, we tried to improve cell adhesiveness of substrates by coating poly-L-lysine.

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This paper describes a resin-based device to separate living cells using ultrasonic standing wave (USW). Heretofore silicon is used for USW device structure because it has high reflection property and vertical wall can be fabricated by wet etching. But the resin-based device is needed for the permeation property and simple fabrication process. First, we fabricated the SU-8 resist microchannel by photolithographic method in order to obtain the vertical side walls. Then we carried out cell sorting test using the 1μm beads. As a result, we observed the micro beads moving to acoustic nodes and different phenomenon for the silicon structure device.

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This paper presents novel methods of manipulation of single chromosomal DNA molecules for single molecular genomic studies. Chromosomal DNA molecules are, first, extended to the full length by electroosmotic flow. We demonstrated translocation and winding of the extended DNA fibers in solution using optically-driven microstructures. An extended DNA fiber is translocated with a micro-fabricated hook driven by a focused-laser beam. When two optically-driven micro-fabricated bobbins are made into contact with a DNA fiber and the bobbin revolved around the other, the fiber is wound and suspended between them. The combination of the partial DNA manipulation using the hook and the whole manipulation using the bobbins leads to the chromosomal DNA-protein interaction assay in single molecular level.

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Techniques of DNA manipulation are important for molecular biology. In this study, we propose a novel high-throughput DNA fiber assembling method to semi-control DNA positioning. We fabricated SU-8 microbridges using the Single Mask Inclined Photo-Lithography Expose (SIMPLE) process, and stretched the human chromosome on those microbridges by centrifugal force. Then DNA fibers can be stretched separately on microbridges, which are called a Genetic Extended-fiber Network (GEN). By performing Fluorescent In Situ Hybridization (FISH) analysis, the validity of GEN using the microbridges for DNA analysis was confirmed.

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We demonstrate to modify DNA by coating Pd nano particle and measured an electrical characteristic of the DNA-Pd wire using the DNA tweezers. In this paper, we report a high sensitivity piezo-resistance measurement of DNA-Pd wire. The wire is prepared capturing between the probe tips of the tweezers. An AFM probe (spring constant: 0.02N/m) can be used for giving a displacement to the wire and the displacement is also detected by AFM system. An electric current through the wire was monitored by lock-in-amplifier applying 0.1Hz sine wave voltage. I-V curves of the DNA-Pd wire were measured just before bending and during 800nm bending of the wire respectively. The resistivity of the fabricated Pd wire was estimated to be 16.9Ω・cm. The resistance of the wire was changed from 0.429Ω to 0.453Ω by the extension. As demonstrated here, this method is useful for an electro-mechanical evaluation technique of nano materials.

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Nowadays, precision instruments play a vital role in performing surgery inside of a human body. The instruments require micro motor which comprises of several micogears, and producing those complicated tooth shy of microgear is a huge challenge for gear engineers. Using bulk metallic glass to fabricate microgear could reduce the difficulties faced in manufacturing process and it is also expected to extend gear life cycle. This paper deals with developing a metallic glass micro gear performance tester through evaluation experiments of its basic strength and failure mode.

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This paper describes evaluation of bond strength in MEMS soldering package heated by using Al/Ni multilayer film. Al/Ni multilayer film deposited by DC magnetron sputtering shows self-propagating exothermic reaction. By applying a spark to the reactive film, the film generates heat enough to melt eutectic solder film. The heat of reaction depended on Al/Ni bilayer thickness and the total film thickness. We used the Al/Ni multilayer film as a local heat source in MEMS soldering packages. The solder film-bonded silicon elements by the local heating was fabricated without other external heat sources. The bond strength examined by blister test for package was evaluated by weibull distribution.

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This paper describes a novel micromotor using surface tension of liquid droplets. As the dimension of mechanical elements decreases, surface tension becomes dominant compared to gravity force, and it often causes adhesion problems between two surfaces. On the other hand, recent studies show that surface tension can be utilized for transportation of liquid droplets and lubrication of hydrophobic surfaces. In this study, a micromotor that is driven and lubricated by surface tension of water droplets has been developed. The motor consists of stator electrodes, water droplets and a rotor. The water droplets are transported on the stator by using electrowetting on dielectric (EWOD) and a rotor is supported and rotated by the droplets. A rotor of 5-mm diameter was successfully rotated at 320rpm.

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This paper describes a molding method using a precise micro-die and a ultraviolet light hardening type resin to realize a large amount and low cost production of the planar light waveguide device which is essential for the optical communication and the light control fields. In particular, we examined the Arrayed Waveguide Grating (AWG) which can be used for the Coarse Wavelength Division Multiplexing (CWDM) system. For this purpose, we have designed and analyzed the parameters of the AWG. A Si master block for the AWG production was fabricated by the photo-lithography technology and the dry etching technology. Furthermore, the micro-die was made by the Ni plating and removing a Si master block. Finally, the AWG was molded by the ultraviolet light hardening type resin using the Ni micro-die.

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Recently, high aspect ratio structure forming is important technology to apply for the sensing device and micro pillar array structure. In a general way, a dry etching process using ICP-RIE (inductively-coupled plasma-reactive ion etching) is well known to fabricate the high aspect ratio structure. However, using Deep RIE generates the scalloping of the sidewall. This paper proposes the high aspect ratio shape forming technology using Si crystal anisotropic etching. In this method, we fabricate the high aspect ratio micro pillar array using (110) Si crystal by TMAH wet etching. As a result, we confirmed the principle for the high aspect ratio structure forming only by using a wet etching process, our proposed method has features of lower cost than ICP-RIE and good surface roughness.

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This paper describes a new fabrication process of a micro elliptical collimator lens to form a beam shape for a LD (Laser Diode). The beam shape of LD is an ellipse because the divergent light angle is different between horizontal and vertical direction. In this presentation, we propose the lens to form the divergent light of an elliptical beam shape to the collimated light of a circular beam shape. For this purpose, we designed one lens, which has different curvature radiuses between the incident and the output surfaces. In the incident surface, the divergent light is formed to the convergent light, and the convergent light is formed to the collimated light in the output surface. We simulated the optical, characteristic of this lens, and designed for various parameters. In order to fabricate this lens, we propose a new process using a chemically absorbed monomolecular layer, which has an excellent hydrophobic property. This layer is patterned and deposited by a photolithographic technique. Next, we drop a UV (Ultra Violet) cure material on the hydrophilic area, as the result, we can fabricate a micro elliptical lens shape. The formed lens shapes are transferred by the electro-plating and then the micro dies are fabricated. By using this micro die, we can fabricate the micro elliptical lens.

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In advanced information technology, large amount of data is 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 optical aberration for multilayered disk media. This paper proposes MEMS-Based aberration free mirror micro actuators using PZT thin films. 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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Recently, large capacity and high track density optical disks have been developed. In such optical storage devices, it is important to develop the positioning control mechanism with high accuracy and high speed in order to control and reduce the tracking error due to the disk radial run out in optical disks. Therefore, this paper proposes the MEMS-based mirror actuator mechanism using PZT thin films. This MEMS mirror fabricated by using silicon micro machining technologies and the characteristics were evaluated. As a result, it was confirmed that the proposed mechanisms have good static and dynamic performances.

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We have developed small sized and low-loss MEMS switches for RF applications. Our MEMS switch is a cantilever type that is an integral structure with a signal line. The device size is 150μm by 60μm, which is one of the smallest in the reported MEMS switches. Our MEMS switch has a high resistance bias line between an electrode and a bias pad. The high resistance bias line gives the decrease in the insertion loss, because it prevents a signal from leaking to the bias pad. As a result, we achieved RF characteristics as 0.26dB insertion loss and 18.1dB isolation at 20GHz.

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In this study, a novel technique of wafer-level automatic integration of Surface Mount Devices (SMD) on silicon microchips and its application to ubiquitous microsensor devices are presented. One of the important problems in networked sensing systems is power supplying method to each sensor node in the sensing system. We have proposed fully wireless silicon microsensor node driven by RF power transmission for realization of battery-less power supply system in ubiquitous sensor networks. Integrating large capacitor by SMD technology with ubiquitous sensor microchip, the maximum drive capability and the efficiency of the on-chip power receiver (RF-DC converter) for total system drive is so much increased. Self-assembly of SMD on silicon-wafer can be automatically performed by means of both gravity force and vibration. The concept, experimental results, and an application example to RF-powered circuit are presented.

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For high-resolution retinal camera, we have developed an adaptive optical system with a silicon-membrane deformable mirror (DM), which is electrostatically actuated by 85 electrodes. The square voltages applied to the electrodes are mathematically calculated by a linear combination of base templates, each of that approximately forms a specific Zernike-modal shape. We present a derivation method how to obtain new templates. The suitable coefficients for the template combination are derived by the least-squares method. By using the method, we have successfully improved the wavefront compensation performance in the adaptive optics with the DM.

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To apply an adaptive optics to a retinal camera, we developed an electrostatic driven DM (Deformable Mirror) with 85 electrodes. At now, there are two kinds of DM. One is a division mirror type that mirror structure has a minute mirror array, and the other is a continuous mirror type that mirror structure is a one membrane. We selected a continuous mirror type, because it was simple structure and could correct for larger wavefront aberration. However, there was a trade-off that the control method becomes complex. So we performed FEM (Finite Element Method) based Electrostatic-Structural coupled analysis with consideration of internal stress to predict DM deflection. As a result, the FEM simulated results showed good consistency with the measured results.

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A new on-chip tensile testing device using electrostatic actuation and detection was designed and fabricated from an SOI wafer to evaluate the mechanical properties of carbon nano materials such as carbon nano-tubes and fullerenes. In this device, force is generated by electrostatic comb drive actuator and tensile force on specimen is measured as the deformation of force-measuring spring. The specimen elongation and the spring deformation are detected as capacitance changes. As a result of design, we predicted high resolution of elongation and tensile force, which are 1nm and 1nN respectively. In order to assemble carbon nano-material on this device, a new technique for fabricating a free-standing fullerene nano-wire was proposed. This wire was fabricated using electron beam writing and sacrificial dry etching. By irradiated vacuum-deposited fullerene thin film with electron beam, polymerized fullerene nano-wires were patterned. Then, the doubly-supported beam structure of the fullerene nano-wire was obtained by sacrificial dry etching using XeF_2 gas.

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HBC nanotube bundle is trapped and mechanically tested by MEMS tweezers. HBC nanotube is macromolecule which has helical structure. Molecular Tweezers and Tweezers for Electron Microscopy (EM tweezers) is used for trapping HBC nanotube bundle. Dielectrophoresis is used for trapping by Molecular tweezers. Electron Microscopy observation is capable during tensile test using EM tweezers. We have successfully measured 1MPa in young's modulus of HBC nanotube by two type tweezers.

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It is necessary to study the characteristics of materials in atomic scale because electric devices are scaling down to nanometer size. In nano scale, the peculiar structures and phenomena on the surface of materials ware observed. Nano-contact is one of the important atomic scale structures to investigate such nano scopic phenomena. In this paper, a MEMS (Micro Electro Mechanical System) device with movable opposing tips was fabricated to observe nano-contact. This device is actuated electrostatically in the transmission electron microscope (TEM). And tilt-evaporation which can make hetero-material opposing tips was proposed and inspected.

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This paper proposes a new composition of a 2D array SPM system using optical interference fringes for a parallel nano imaging in a large area scanning. We achieved large-scale integration with 50,000 probes fabricated with MEMS technology, and measured the optical interference patterns with CCD. We designed, fabricated, and evaluated the characteristics of the probe. We took some interference patterns by CCD and measured the position of them. We calculate the probe height using the interference displacement and compared the result with the theoretical deflection curve. As a result, these interference patterns matched the theoretical deflection curve. We found that this multi-probe chip using interference patterns is effective in measurement for a parallel nano imaging and confirmed the feasibility of a 2D array SPM system.

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We describe a new class of atomic force microscope (AFM) which provides tweezers function in addition to atomic force observation. In order to integrate a function of nano-manipulation with AFM, we have developed new micromachined tweezers, named AFM tweezers. This device has two wedged probes at the end of cantilevers; one is used for AFM observation (sensing probe) and another (movable probe) for grasping a small object which is just observed by the sensing probe. The integrated functions of AFM observation and manipulation enables us to do a precise approach even to a small object which cannot be observed though an optical microscope; consequently successful manipulation is realized. Moreover in order to develop the AFM tweezers, we have designed software for operation of the AFM tweezers which can be installed to SPA400 AFM system (SII Nanotechnology Inc.). In this prototype software, manipulation sequence including approach, grasp, and pick-up is automated.

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The atomic force microscope (AFM) has been widely used for research of nanotechnorogy. for instruments Recently, we analyzed machine immitance of the comb-drive actuator, and observed clear nonlinear characteristic of the machine admittance near the resonance frequency. We made a probe with comb-drive actuator. When the probe touched to the substrate, we found out that the mechanical immitance characteristics near the resonance changed. It is possible to make a device, it is able to measured ruggedness image using that characteristic. In addition, we observed self-oscillation in this device with a circuit make a positive feedback loop. This is same as characteristic of a crystal oscillator. Self oscillation frequency of comb-drive actuator is change when the probe touched the opposing substrate. We make a PID control circuit for control a stage, therefore the probe was hold soft contact position with opposing substrate. While the probe hold this position, it scan XY plane, we observe ruggedness image.

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In biological, chemical, and medical analyses, the mechanism of particle motion at near-surface is greatly attracted attention for prediction of chemical characteristics such as reaction time and efficiency in micro chip. In this paper, we developed observational method of 3-D particle motion at near-surface used evanescent wave and PTV. A precise measurement was developed for calibration of position of particle in direction of depth. And we evaluated Brownian motion and concentration distribution of polyethylene latex particle (diameter 100nm) motion at near-surface in micro-channel. The results show Brownian motion is hindered as particle close to wall. In addition, the concentration is the lowest at near-surface and shows the largest value at specific location from wall. The location is consistent with theoretical particle-wall minimum potential location.

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A web is continuous flexible materials such as paper, plastic film, thin metal plates etc. Before being converted to the final product, the web undergoes several processes, for example, transportation by the drag roller, press, printing, coating, drying, slittering, winding, and so on. Under such processes, the web is given the additional values to enhance the quality and function of product. When the web defects, such as slippage, wrinkling, star defect and telescope, are generated in the web handling processes, the web defects immediately result in quality loss. Therefore, to predict and protect the web defects is very important engineering problems in web handling industries. This key note paper describes the recent research topics treating how to predict and protect the web defects based on the theoretical model with experimental verifications.

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A web is continuous flexible materials such as paper, plastic film, thin metal plates etc. Before being converted to the final product, the web undergoes several processes, for example, transportation by the drag roller, press, printing, coating, drying, slittering, winding, and so on. Under such processes, the web is given the additional values to enhance the quality and function of product. When the web wrinkles are generated in the handling processes, the wrinkles immediately result in quality loss. Therefore, to predict and protect the wrinkles is very important engineering problems in web handling industries. It is well known experimentally in the web handling industries that web wrinkles are generated due to misalignment of roller. Based on such experiences, several investigators successfully formulated the prediction model of wrinkles for isotropic webs with constant Young's modulus in machine and cross machine directions. However, some anisotropic materials such as paper and some optical films used for the Liquid Crystal Display have different Young's modulus in machine and cross machine directions. In this paper, observation method is presented for web wrinkling and the prediction model of wrinkling is proposed with experimental verifications.

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This paper describes the theoretical modeling for the prediction of slippage onset condition between web and steel roller with experimental verifications. For the first step of modeling, the occurrence of slippage is observed far the cases of uncoated paper (newsprint) and coated paper and optical films and the relation between the slip ratio and roller velocity is measured by changing the web tension. Theoretical model is formulated based on the observed results, and the predicted results by the model are compared with the experimental results. From the results obtained, the applicability of the model is confirmed experimentally.

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This paper describes the pressure characteristics of the transporting web handling roller with different types of permeability To be utilized in the experiment, two kinds of web, i.e. a newsprint and PET film were taken up. The pressure distribution of the rotating guide roller is measured to be offered for the use of a pressure transducer with a view to combining the behavior of the web wrap angle, web tension, web width, and rotating roller speed. In addition to the above, velocity distribution between the web and rotating roller was measured in the inlet and outlet region by PIV. From the experimental results, it is explained how the hydrodynamic behavior is with respect to the two types of web with different permeability. The vortexes are generated in the inlet region, whereas the reverse flow is produced in the outlet region. The spike-shaped change was in consideration based on these phenomena.

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This paper describes the optimization method of winding tension for preventing the wound roll defects, mainly the star defects and slippage, based on the optimum design technique. In the analysis of in-roll stress distributions in the radial and circumferential directions, Hakiel's nonlinear model with and without air entrainment effects is basically applied. It is well known experimentally that a decrease in the winding tension has the effects of preventing the star defects due to negative circumferential stress under winding. So, in the present optimization method the winding tension is gradually decreased in the radial direction to minimize the averaged value of circumferential stresses, under the constraint of non-negative circumferential stresses. The successive quadratic programming (SQP), which is the typical mathematical programming method, is used as the optimization technique and the winding tension is expressed by the 3rd order spline curve of radial coordinate. The liner function with respect to radial coordinate is used as an original winding tension. The optimized winding tensions are obtained for various winding conditions, and it is confirmed that the in-roll stress distributions are very much improved by the present method.

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Predicting the behavior of sheets with a high degree of reliability is important when designing sheet-handling machinery. Automated teller machines, in particular, require the deformation of each bill in the feeding mechanism to be analyzed to predict the reliability of the mechanism. We, therefore, developed a simulation method that can predict the behavior of sheets in an overlap-type sheet separating mechanism under various conditions by means of a finite element method. To predict the reliability of its mechanism, we also analyzed deformation forces by means of Clapeyron's theorem. We derived a formula that showed the relationship between the deformation forces and coefficients of friction of the rollers in its mechanism, which is useful when designing the sheet separating mechanism.

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A preliminary investigation has been conducted on the control of a micro-droplet in electrostatic inkjet phenomena, because the electrostatic inkjet has a merit that the formation and locus of the droplet can be controlled by the application of the electric field. It was observed that a Taylor cone of the ink was formed at the tip of a tube and the tip of the cone was broken to form a very small droplet. It was demonstrated that highly fine image, 2,700dpi Kanji character, was printed on a paper utilizing this phenomenon.

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We have studied dynamics of magnetic brushes in two-component magnetic development system of electrophotography by a model experiment and the numerical simulation with the Distinct Element Method. Axial and lateral forces of chain-like brushes applied to the photoconductor were measured to clarify the relationship between the lateral friction force and the diameter of carrier particles, magnetic flux density, and the brush length. It was observed that the force was increased in accordance with the increase of the magnetic flux density and decreased with the brush length but the particle diameter did not affect the total force. On the other hand, the numerical calculation deduced that although the total force is not affected by the particle diameter, the individual differential force of the chain was small and the density of contact points of brushes was high for small particles.

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Olympus Corporation recently founded a new research laboratory the Future Creation Laboratory, based on its management principles "social involvement, social insight, and social inspiration." This laboratory is committed to pursuing a variety of research projects by identifying and creating social values for enriching people's lives in the future. Instead of simply predicting the technological future needs, our actions start with imagining what people really want in the future, and creating and sharing visions with strategic partners of both academia and industries worldwide. To accomplish such actions, the laboratory organizes a flexible management style that enhances originality of ideas by individual researchers, and that also leads to a new collaborative framework and an open innovation process. In this paper, I present the concepts and the practices of this innovative management as well as research activities in the Future Creation Laboratory.

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A method for measuring the aerodynamic excitation force of the rotating fan has been developed. In this study, the aerodynamic excitation force of the rotating fan was measured using test system with a four-bladed fan, an induction motor, pressure gauges, and a high-stiffness wall. The aerodynamic pressure of the rotating fan makes several peak frequency components that are Nz-frequency excitation force. "Nz" is [Rotational speed of motor "N"×Number of fans "z" (Hz)]. We used the static pressure previously measured to analyze the vibration response of a thin plate structure. The thin plate structure was a 900×740×3.5mm aluminum plate lies at a distance of 10mm to 7mm against the fan. To calculate the vibration response of a thin plate excited by the aerodynamic force of rotating fan, the measured pressure was transformed into the excitation force and phase angle. Acceleration response of the thin plate excited by the rotating fan was determined by using the transformed force and the F-E model. Only the basic frequency of blade-passing component, at which the largest pressure occurs, was used in this calculation. Using the transformed force and phase of rotating fan, the vibration response of a thin plate structure was accurately calculated.

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This paper is concerned with gas leakage fault detection of electromagnetic valve using a neural network filter. In modem plants, the ability to detect and identify gas leakage faults is becoming increasingly important. The main difficulty to detect gas leakage faults by sound signals lies in that the practical plants are usually very noisy. To solve this difficulty, a neural network filter is used to eliminate background noise and raise the signal noise ratio of the sound signal. The background noise is assumed as a dynamic system and the accurate mathematical model of the dynamic system can be established by a neural network filter. The predicted error between predicted values and practical ones constitutes output of the filter. If the predicted error is zero, then there is no leakage. If the predicted error is greater than a certain value, then there is a leakage fault. Through application to practical pneumatic systems, it is verified that Neural Network filter was effective in gas leakage detection..

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To reduce the number of traffic accidents from driver's misunderstanding of headway distance, driver's subjective sense error correction method is proposed. First the subjective sense error is estimated using a back-propagation neural network. Then the method provides a warning based on the estimated driver's subjective sense of headway distance. A warning threshold value change mechanism is applied for reducing driver distraction. The threshold for starting providing warning is adjusted according to the vehicle's acceleration and speed relative to the car running just ahead of the driver. It was tested successfully on 7 people, reducing the subjective distance error up to 3%. The model is built in order to make it adaptable in real time to the changes in driver's subjective sense of headway distance. This proposed method can be implemented on conventional devices (such as a Head-Up Display, HUD), in order to reduce car collision accidents.

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A risk estimation system based on Bayesian Networks using a driver model is proposed for achieving a risk estimation function in traffic situations for safe driving support systems. The proposed system uses input traffic and vehicle information to evaluate subsequent driving operations such as acceleration and steering using Bayesian networks. The vehicle trajectory is then forecasted using a dynamical physical model. Next the risk of collision with other vehicles is calculated by considering the trajectories of other vehicles and the possible trajectories of the car itself based on the output probabilities of the Bayesian network and the predictions of the dynamical model. In the scene of the intersection, the effectiveness of the proposal system is shown by comparing in the simulator the scene where the accident occurs to the scene where it does not, and then specifying the difference between the risk transition coefficients of both cases. In the future, the proposed system can be applied to a system that prevents traffic accidents by giving to the automatic control system of the vehicle the optimal evasion driving operation.

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We research physical relationship between actual sound of including clear peaky frequency and their corresponding onomatopoeia and utterance sounds. First, to explore the connection between peaky sounds and their corresponding onomatopoeia, we created sounds based on the linguistic information of onomatopoeic words. We then carried out an auditory perception experiment using these sounds. Then we specified that the frequencies of a sound perceived to be an onomatopoeic word. And we found that the frequencies of a sound perceived to be an onomatopoeic word are similar to the frequencies comprising the corresponding actual sounds. Second, we explored that relationship between the frequencies of a sound perceived to be an onomatopoeic word and utterance sound. Finally, we found that a human auditory sense is extremely influenced from the vowel utterance sound.

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We have performed basic experiments for the purpose of applying onomatopoeia to engineering problems. In these experiments, test subjects were made to perform lifting actions while listening to onomatopoeic utterances. We thereby demonstrated that there is a relationship between onomatopoeic utterances and the lifting forces exerted by the test subjects. Here, we examined how the lifting forces are related to the way to utter onomatopoeia to make test subjects to exert light force. Human can utter the onomatopoeia with various "nuance". For example, we can "bellow", or "whisper". Then, we investigated how the lifting force is affected depending on this "nuance" that is expressed in human onomatopoeic utterance.

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It is a common knowledge for safety engineers to perform machine safe measures based on the risk reduction process described in ISO12100. However, as there are many "hazardous point near by operation" or the work in large scale industrial field, it is very difficult to apply above safe measures. The supporting system for safe work of operator using the database related to risk information, communication system using personal type information terminal, or discrimination or warning system was proposed. It was also indicated that these systems were effective in order to reduce the fatal accident in industrial field.

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We have been developing a 4DOF exoskeleton robot system in order to assist shoulder vertical motion, shoulder horizontal motion, elbow motion, and forearm motion of physically weak persons such as elderly, injured, or disabled persons. The robot is directly attached to a user's body and activated based on EMG (Electromyogram) signals of the user's muscles, since the EMG signals directly reflect the user's motion intention. A fuzzy-neuro controller has been applied to control the exoskeleton robot system. In this paper, controller adaptation method to user's EMG signals is proposed. The experimental results show the effectiveness of the proposed method.

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Since three-axis tactile sensing has good advantages on grasping an object of unknown mass and hardness, we developed a multi-fingered robotic hand equipped with a hemispherical three-axis tactile sensor on the fingertips. A controller and a tactile processing system for the robotic hand are developed to implement distributed processing and communicate tactile information using TCP/IP protocol. The algorithm of the controller decides the fingertip velocity on the basis of variation in sharing force and normal force increment: the variation in sharing force is used as information for judgment of touching or slippage; the normal force increment is used as information for recognition of the object hardness. To evaluate the algorithm, we conducted a series of experiments, in which the robotic hand grasped same size blocks of aluminum, Styrofoam, and soft paper. As a result of the experiments, the robot succeeded in grasping these objects possessing various kinds of hardness and yield force.

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Our aim is to develop the system that take someone by the hand and teach him step by step. By using this system, we instruct ideal motion like the throw motion of baseball, the pose of the dance, and the application of craftsmanship. It is necessary to measure learner's joint angle. In this paper we propose a novel system that measures the joint angle with bend sensors. The bend sensor doesn't disturb movement because it is light and soft. Concretely, it measures the joint angle of articulatio humeri (2-DOF). To ease the nonlinearity of the sensor and the influence of the mutual interference between sensors, we have done the calibration of two dimensions. From the experimental results, it is confirmed the improvement of the measurement accuracy.

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The rational formula of robots was proposed. The axis direction of the motor which composes a robot is classified by Yaw axis, Roll axis and Pitch axis. When there is a motor on the body side, the initial of axis is written with a capital letter, and written with a small letter in case of opposition. The leg of SANSYRO II developed in this laboratory can be written with "Leg=RP-p-PR". The whole structure of the robot is expressed as rational formula of the robot to show molecule structure in chemistry. SANSYRO II is expressed as a rational formula of the robot with "16=Head-Y-Arm-Y-Leg(Arm=Pr-0-0)_2(Leg=RP-p-PR)_2". And, the first stage prototype was proposed. Servo-motors, C form parts and box parts are combined, and the trial production of the robot can be done easily.

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We designed and developed a quasi-passive dynamic walking robot with swinging torso, and we confirmed flat plane walking as well as slope climbing by experiments. Past experiments were static walking, but this time we experimentally realized dynamic walking where inertial force was considered. From the heuristic searches by changing swinging period of torso, we found several patterns in the results. They were compared with walking speed and the walking pitch. Then we discussed the walking condition depending on the swinging of the torso.

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