In this paper, medical devices for assisting therapy under MRI guidance are introduced. Recent advances of the interventional MRI (Open MRI surgery) have been promoted to achieve minimally invasive surgery. As basic components for MRI compatible devices, three researches are introduced : a surgical manipulator for needle placement, a pneumatic saw-tooth stepping motor, and a non-metal display inside the MR gantry. A mere introduction of the conventional robot/electrical & mechanical devices should be avoided because it will probably disarrange the strong magnetic field in MR environment and cause image distortions. The application for therapy and the required image resolution are described and some advanced MRI compatible device researches are also discussed.

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The stochastic resonance (SR, hereafter) is one of the basic principles intrinsically possessed by any living thing to highly adapt for the complicated environment including various disturbances. It was found that Hodgikin-Huxley model capable of emulating living neuron activity shows the SR. A system of two differential equations dominating Hodgikin-Huxley model is similar to a differential equation system for Belousov-Zhabotinsky (B-Z, hereafter) reaction, which is one of phenomena caused by complex science systems. Although a noise is mixed inevitably by contact with an object and sensor's movement on it in tactile sensing, a human being can evaluate the several micrometers unevenness on the object surface by means of the SR. If the SR mechanism is incorporated into a tactile sensing system, the system can measure an object surface with high precision in not only the controlled environment adjusted like a precision measurement room but a living environment In our laboratory, we intend to apply remarks obtained from complex science systems such as SR and B-Z reaction to robotic systems such as a tactile sensing system and a tactile display. Some resent topics of our results are described in the presentation of HP 2008.

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Noninvasive electroencephalogram (EEG)-based brain-machine interface (BMI) provides a new communication channel to replace an impaired motor function of patients. EEG recordings during right and left motor hand imageries are expected to be available to move a cursor on a computer screen or to move a wheelchair. In the present experiments, visual cues ("right hand" or "left hand") were presented. The subjects were asked to move one of their hands or imagine it when visual cues were presented. First, blinking artifacts were eliminated by using ICA. Secondly, spline Laplacian analysis was applied. Thirdly, the most significant channel, latency, and frequency band were determined for the discrimination based on time-frequency analyses with wavelets. Lastly, in their parameters, trials were discriminated between right and left hand movements or their imageries. The highest percent correct of the discrimination in the 5 subjects was over 70%, indicating the presented method may be applicable as a BMI.

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This paper presents a concept of perception assist with a 3DOF active stereo vision camera system for a 4DOF upper-limb power-assist intelligent exoskeleton system in order to help daily activities of physically weak persons. The proposed active camera system has the capability of moving the camera to a better position to monitor the end effecter of the exoskeleton all the time hence the stereo vision digital camera can be used to monitor the user's interaction with the environment effectively. Based on the environmental information captured by moving camera and other sensors of exoskeleton, user's motion can be modified if problems are found in user's motion. The effectiveness of this proposed system was evaluated by performing experiments.

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In this paper, we propose an active indicator for haptic recognition by figure. It is a finger giding system that tries to improve the accuracy and the speed of the haptic recognition. The ordinary haptic indicator systems are considered to indicate passively the accurate figure, but not considered the accuracy and the speed of recognition. The proposed method is not only passively but also actively indicating the figure to improve them. We designed an actual active indicator to compare the 3 methods, an active indicating method, an passive indicating method and an active and passive method. As a result, An active and passive method was best for a skilled man (who used the active indicator many times), and an active method for a unskilled.

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[in Japanese]

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Optical topography (OT) signals measured during an experiment using activation tasks for certain brain functions contain neuronal-activation-induced blood oxygenation changes and also physiological changes. We used independent component analysis (ICA) for separating them, and extracted components related to brain activation without using any hemodynamic models. The analysis procedure has three stages: first, OT signals are separated into independent components (ICs) by using time-delayed decorrelation algorithm. Second, task-related ICs (TR-ICs) are selected from the separated ICs based on their mean inter-trial cross-correlations. Third, the TR-ICs are categorized into two clusters by k-mean clustering method and these are classified into TR activation-related ICs (TR-AICs) and TR noise ICs (TR-NICs). We applied this procedure to analysis of the OT signals obtained from experiments with one-handed finger tapping tasks. In the averaged waveform of TR-AICs, a small overshoot can be seen a few seconds after the onsets of each task and a few seconds after the ends, while the averaged waveform of TR-NICs show an N-shaped pattern.

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This paper presents the new warning method to increase the driver's sensitivity for recognizing hazardous factors in the driving environment. The method based on "Subliminal effect ". By performing many experiments to 6 subjects, the response time for detecting flushing marks tends to be decreased when the subliminal marks are shown up in advance. Finally, the paper proposed the scenario for implementing this method to real vehicles.

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We have developed a method for the assessment of speech comprehension, using a one-minute long electroencephalographic (EEG) signal, hi two experiments, EEGs were recorded from Japanese speakers while they listened to 51 or 46 seconds-long stimuli, which were Japanese and Spanish speeches modulated in amplitude by binary m-sequences and played forward and backward. A circular cross-correlation function was computed between the EEG signals and the m-sequences and averaged across the subjects. Independent component analysis of the averaged functions revealed a component response which was obtained only for the comprehensible Japanese and not for the incomprehensible reverse or Spanish stimuli, as a Cz-CPz-Pz dominant correlation peak with a 400ms delay. This technique is 1. suitable for natural continuous speech stimuli, 2. capable of assessing responses to various aspects of speech comprehension by modifying the modulation, without being influenced by the subject's intention, 3. highly efficient in acquiring signals, 4. feasible for a real time application for its computational simplicity, and 5. resistant to artifacts for differences in time constants.

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The test subjects were asked to push forward force-operating-joystick while listening to white noise with square envelope. The sound and the operating force measured simultaneously. It was cleared that there were variations of operating force depending on experimental date and individual. We have built a system that has auditory-feedback control system for the operating force to follow set point. We performed experiments on fixed command control using PI controller with various control parameters. The appropriate control parameters for individual were discussed using three parameter-tuning methods. Consequently we found that Cohen-Coon's parameter-tuning method was most appropriate in the system.

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A new combinatorial method to deposit metallic thin films using an arc plasma, combinatorial arc plasma deposition (CAPD), was applied to search for novel compositions of thin film metallic glasses (TFMGs) as new MEMS materials. The CAPD setup includes three arc plasma guns (APGs). with each gun shooting a pulse-like plasma of constituent elements at specific time intervals to deposit a compositionally-graded metallic thin film on an SiO_2 substrate. First, a Pd-based compositionally-graded thin film was deposited to search for the lowest resistivity composition of Pd-Cu-Si TFMGs. As the result, the Pd_<81>Cu_5Si_<14> at.% sample showed the lowest absolute resistivity of 64 μΩ・cm and a supercooled liquid region (SCLR) temperature range (ΔTx = Tx - Tg) of 50K. Next, we found out a novel Ru-Zr-Al TFMG by CAPD. Differential scanning calorimetry revealed that the two sputter-deposited samples Ru_<65>Zr_<30>Al_5 and Ru_<67>Zr_<25>Al_8 had a SCLR. Moreover, the samples exhibited superior mechanical properties.

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A drum-type washer dryer with a drum 600mm in diameter which was the largest in the domestic drum-type washer was developed. Using the large drum, both performance in washing and quality in drying are improved. However, during spin cycle, the large drum generates huge centrifugal force and large vibration. This report presents three vibration reduction technologies. First, we optimized parameters of suspensions using Taguchi Methods on computer simulation. Second, 2-stage oil damper which can change its characteristic by vibration amplitude was developed. Third, two vibration sensors were installed to detect vibration modes, and using those data spin speed was controlled. Applying those technologies, a low-vibration drum-type washer dryer was developed.

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Today, drum type washer dryer is widely spread drastically in Japan. The preferred requirements for washer dryer are lower electric consumption, and faster drying. Furthermore, it is very desirable to reduce wrinkles drastically after finished drying. We developed new high-quality-finish technology to smooth wrinkles with new concept of blowing high-speed hot air directly to cloths while drying. To optimize the parameters to get the satisfactory finish, we clarified the relationship experimentally between airflow speed, air quantity, cloths weight, and capacity of drum. To realize the condition above, we developed new high-pressure type fan motor, and applied it to the drum type washer dryer released in October 2007.

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This paper describes operating characterization of MEMS blackboard type display which is proposed and confirmed the actuation by Roi Shigematsu in 2006. This display is electronic re-writable blackboard that keeps the trace of finger-drawn strokes using the bitmap of scatting light from segmental membrane. Images can be erased entirely or partially by releasing voltage or pulling back the membrane with magnetic force, respectively. Pixels of this display consisted of square line type but we propose new type pixels, square dot type and hexagonal line type pixels and evaluate by measuring hysteresis.

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This paper describes a development of an optical micro-actuator that uses the photothermal effect. Photothermal effect has advantages, such as high-speed responce by the miniaturization, the noncontact energy supply and control, and material independenc method. Actuator can be expected the increase of displacement by employing the bimorph structure, and can gain maximize driving force by small optical power. Combination of the stainless steel and the photoresist, whose difference in the coefficient of linear expansion is large, is selected as a bimorph structure. An arch type inch worm made of the stainless steel and the photoresist is produced with the simple micromachining. For the driving of the arch type inch worm, speed of 0.2mm/sec is obtained by the laser irradiation frequency of 2Hz, and the speed of 0.1 mm/sec is obtained by 1Hz in the acrylic resin pipe.

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In this paper, we propose innovative liquid pumping devices for μTAS. In this system, microchannels were fabricated in silicon substrates of silicon on insulator(SOI). The vibrating wall was composed of piezoelectric PZT thin films deposited on the Si device layer of the microchannel. The active microchannel can transport liquid by traveling wave induced on the surface of the piezoelectric vibrating channel by applying sinusoidal voltages to each patterned top electrodes with different phase. The active microchannel of 200μm wide was fabricated by the deep reactive ion etching(DRIE) process. The displacement profiles of the vibrating wall and frequency response were measured by a laser Doppler vibrometer. Maximum displacement was about 50nm at the applied voltage of 1kHz and 20Vpp. Mean flow velocity of about 16μm/s at primary resonance point of 573kHz and 32μm/s at secondary resonance point of 859kHz were achieved at 20Vpp. Because of the simple structure without valves and diffuser, it is suitable for the integration into μTAS devices.

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Piezoelectric MEMS deformable mirror resolution is studied for an adaptive optics device. In previous study, we have developed the piezoelectric MEMS deformable mirrors which have 19 actuator away. To improve the resolution of the deformable mirror, we designed the best electrode size to deflect 5μm when applied 10Vpp. Then, we compared 61CH electrodes with 91CH electrodes in terms of Zernike generation. Zernike polynomials are used to evaluate the mirror surface, and the control system is based on the influence functions for generating Zernike modes. As a result of simulation, we proposed 61CH hexagonal electrodes. The displacement profiles measurements by a laser Doppler vibrometer showed that the each actuator generated displacement of 1.0μm〜1.3μm at 10V. Furthermore we calculated residual RMS of Zernike modes(〜27th) of fabricated deformable mirror.

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Ubiquitous sensor network will be an important role in various social systems for environment, safe, security, medical and so on. Sensor network needs a power supply systems for a wireless communication systems. However, a battery power supply system has to change a battery because of its life time. On the other hand, an electric power generation system has a possibility of non-maintenance. In this paper, we propose a micro electric power generation device using a ferroelectric film. A PZT film as a ferroelectric material is formed on a micro cantilever, and an electric power is generated when the cantilever is bended and stressed by piezoelectric effect. The device is fabricated by MEMS technique. The cantilever had 1200 μm in length, 600 μm in width, and 50 μm in thickness. We evaluated the power generation device. The resonant frequency was 8.81 kHz and the maximum displacement was 3.51μm. We achieved a 418 pW generation under the optimum impedance condition.

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This paper reports a dynamic control device for surface acoustic wave (SAW) modulation by using grating structures and periodic convex structures. A grating structure between transmitting and receiving IDTs and a periodic convex structure for putting into the grating structure was fabricated to control dynamically a surface acoustic wave. We used LiNbO_3 for piezoelectric substrate, and Silicon for periodic convex structure. IDTs were designed as 99MHz and 66MHz. It is shown that resonant frequency of IDTs were changed to a lower value by effect of the grating structure and that noise level was decreased by putting the convex structure on the grating structure.

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Recently, studies of positional relationships of cells are seemed to be very important for cell biology. We proposed a novel concept that self-organized vasculature integrates artificial orifices on a device by VEGF (Vascular Endothelial Growth Factor). Sucking and clamping of Alginate Calcium gel beads containing VEGF, it is able to induce angjogenesis to orifices on embedded channels. Endothelial cells have a characteristic property that they organize vasculature by themselves in collagen gel and grow along the VEGF concentration gradient. HUVEC (Human Umbilical Vein Endothelial Cells) were cultured on device for about 7 days in the collagen gel and artificial vasculature were immobilized on orifices by self-organized.

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In the present study, a novel integrated MEMS hematology chip that consists of complete blood count (CBC) sensor, hemoglobin (HGB) sensor and volume measurement sensor, was developed. CBC sensing is based on an impedance method that uses a micro aperture. On the other hand, the HGB concentration and sample volume were measured from optical absorption and optical refraction, respectively. Therefore, the MEMS hematology chip was designed as the laminated structure; i.e. impedance layer (thickness 100 um) including CBC sensor and optical layer (thickness 250 pm) including HGB sensor and volume measurement sensor. The MEMS hematology chip was fabricated using a SU-8 photolithography process, hi addition, the proposed hematology chip was evaluated using an experimental device that simulates a POCT concept hematology analyzer. A trial measurement of control blood was successfully performed. The new MEMS hematology chip demonstrated potential application as a miniature hematology analyzer.

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This paper reports on the extraction of solution from a PDMS microchannel using two forms of liquid actuation by electrical methods. Electro Wetting on Dielectric (EWOD) and Liquid Dielectrophoresis (LDEP). On the Liquid Dielectrophoresis (LDEP) device, upon application of an AC voltage on a pair of parallel electrodes beneath the PDMS microchannel, a liquid finger protrudes from the microchannel exit and advances along the gap between the electrodes. After the voltage is removed, the liquid finger breaks due to capillarity-driven instability and picolitre-sized droplets are formed at specific periodic bumps.

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MEMS tweezers to trap and manipulate bio molecules was fabricated. The gap size was controlled by KOH wet etching and Focused Ion beam process at the range from fifteen nanometers to twenty five micrometers to trap several different size of DNA molecules. We also fabricated the modified design of tweezers to successful trap of DNA, because thermal circulation drags away molecules from tips of tweezers, which occurred by high frequency electric field. These tweezers were tested to trap DNA molecules to verify the function.

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Self-excitation thechnique is known as an effective excitation method for a cantilever probe of the atomic force microscope to measure the surface of a biological sample in a liquid environment. In this research, we deal with a van der Pol type cantilever probe, which is previously proposed to realize the non-contact mode, and experimentally examine the relationships between the response frequency and amplitude and the gap of the cantilever probe and the surface. From the result, the performance of the self-excited cantilever probe from viewpoint of the contact between the cantilever and the surface.

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We have examined a three-terminal comb-drive actuator as a displacement sensor. In our design, a vibrating comb-electrode is sandwiched with a fixed electrode and a movable electrode. When the movable electrode makes a displacement by an external applied force, frequency of the self-oscillated comb-electrode is changed; eventually we can detect its displacement. In this paper, we showed a self-oscillation circuit and oscillation wave form of the three-terminal comb-drive actuator and the experimental result displacement measurement.

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We have developed a new fabrication method of electro-chemical probe for scanning electro-chemical microscopy. In our method, a SiN film, which is used for a mask layer of successive LOCOS (Local Oxidation of Silicon) process, was deposited on a Si{100} wafer and patterned at bottom of an anisotropically etched pyramidal hole. Following LOCOS process formed a SiO2 film except for the area of the SiN film. After removing the SiN film, a gold layer was deposited and patterned; which was then covered with a sputtered SiO2 layer. Final Si substrate etching completed the process. Using this process, we have successfully formed an electro-chemical cantilever which has a small gold probe covered with SiO2 film except for the tip of the probe having the radius of nanometer order.

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Comb-drive actuator operation using the Anderson-bridge is described. The Anderson-bridge is suitable for comb-drive actuator operation because equilibrium of the circuit is obtained by matching of resistances not only for AC but for DC which is required for coupling with mechanical motion and electrical response. We have examined equilibrium of the bridge by measuring bridge output using differential amplifier and tested response of the bridge when external force is applied to the comb-drive actuator.

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Fundamental Performances of the plasma actuator at the low frequency, less than 1,000Hz, was investigated by the PIV method and the evaluation of the power loss. It was observed that the plasma actuator works even at the low frequency higher than 10Hz. The wind velocity was at least 4m/s and the power loss is about 1mW at 10Hz. The estimated energy efficiency was about several tens percent.

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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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In this study, new structure of pneumatic driven microvalves which makes it possible to realize high-density integration has been developed and fabricated to form fluidic analog circuits. Suggested microvalves have vertically formed movable diaphragm on surface of an SOI wafer by using silicon deep etching technology. Accuracy of bonding alignment is not required, because relative positions of the channel and the barrier are determined by one-time photolithography. Fabricated microvalve can control drain flow of air by drain or gate pneumatic pressure like MOSFET characteristics. The occupied surface area of new microvalve is about 1/10 of the previous MOSFET-like microvalve. Based on the design technique of electronic circuits, fluidic-pressure amplifiers were designed and successfully fabricated. As a result, operation of pressure amplification has been demonstrated by the proposed microvalve.

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We developed, for the first time, the manipulation system based on optoelectronic tweezers (OET) which manipulates multiple nano/micro components on an arbitrary substrate with concurrent observation of the component motion. It uses CdS as a photoconductive film. Since CdS transmits red light and absorbs blue light, red light is utilized for the observation and blue light is utilized for the manipulation. The photoconductive electrode substrate which generates the nonuniform electric field for the component manipulation using dielectrophoresis consists of CdS on comb ITO electrode. Using the substrate, it was successfully demonstrated to manipulate a silica particle. Light projected CdS/ITO area had the higher electric field and repelled silica particle. By appling 10 V at 100 kHz, manipulation force of 0.6 pN was induced and manipulated silica particle speed was about 7 μm/s.

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Novel self-assembly process using electrostatic adhesion energy induced by contact electrification phenomenon was proposed and its analytical formulation was performed for the first time. The contact electrification, which is observed when two different metals, such as platinum (Pt) - Silver (Ag) are contacted, was utilized to align a face of a component on a substrate. First, two types of 1 mm square silicon components with thickness of 0.5 mm coated with Pt or Ag and R substrate were prepared. Adhesion energies for two different metal pairs (Pt-Ag and Pt-Pt) were measured by measuring the vibration energy to separate the components from the vibrating substrate. The experimental results indicated the adhesion energy between Pt-Pt was 0.57 nJ, and Pt-Ag was 1.4 nJ on an average. Next, the face alignment experiment was carried out by vibrating the substrate on which 20 components with thickness of 0.2 mm were placed. The front and back face of the components were coated with R and Ag, respectively and they were split into half of R face up and the other half of Ag face up. We could get 83 % components were aligned as R face up. Finally, modeling of the proposed self-assembly process was performed based on the concept of chemical reaction formula. The forward and reverse reaction rates of the face alignment process were determined by fitting the foumula to the experimental data.

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Thought some electrostatic microactuators are proposed for micro electro mechanical systems, the electrostatic force/energy has not been used fully and the output power of the microactuators is small yet. We already proposed the novel drive principle of the microactuator in which electrostatic energy can be converted into a mechanical work efficiently by making electrostatic energy collaborate with the elastic energy. It was named Energy Conversion-type Micro Actuator powered by Collaboration of Electrostatic and Elastic energies/forces, EC-Macbee. In this research, the non-liner spring of the actuator and the fabrication process were designed and we tried to make the drive element of actuator in order to realize this actuator.

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Recent information society, very thin flexible materials such as paper, thin films we call web are used as a media of information, and then they are transported mainly by using friction between web and steel. Therefore, it is necessary to understand the frictional characteristics of them. In this paper, kinetic friction characteristics between paper and steel are investigated experimentally. In the experiment, the type of test rig, low speed type friction test rig, are used for a wide range of sliding velocity. As the result of measurements, it is confirmed that the friction characteristics with sliding velocity and contact pressure are significant.

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This paper reports the measurement of interlayer stress distributions in wound roll. The models that predict distribution of interlayer stress was became complete. The cause of the roll defect is improper internal stress distribution. However, It is scarce that research of measures an internal stress. Then, the winding test machine was designed and produced in this research. The pressure between layers was measured by the FSR method.

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A web is continuous, flexible, two dimensional materials such as paper, plastic film, textile, thin metal etc. then it has various applications in many industries because of their advantage of compactness or anther function. In near future, the market of optical films became very large in some industries such as crystal liquid display, PC, compact IT instrument. On the other hand, it is well known that the web is damaged by wrinkling in transportation of webs. Therefore, it is important to predict and protect the wrinkles. In the past, we presented a theoretical modeling which is considered the effectiveness of anisotropic in Young's modulus of optical film in machine direction and cross machine direction on wrinkles. However there is no literature treated the effectiveness of micro-grooved roller for removing the entrained air on wrinkling. This paper describes the experimental study on wrinkling in optical films transported by micro-grooved roller.

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In the manufacturing fields of optical films, the web handling systems are supported by guides and rollers. In such systems, the moving web brings the surrounding air into the gap between web and roller or web and guide, and then the web is lifted slightly by the film pressure generated due to viscosity of entrained air and consequently it becomes the reason of slippage. To protect the slippage, a micro-grooved roller is used in the manufacturing fields. However, the dimension and shape of micro groove has been decided experimentally. This paper describes theoretical model for the prediction of slippage onset condition between optical films and micro-grooved roller. Theoretical model is formulated, and predicted results by the model are compared with the experimental results. Moreover, the dimensional of micro-groove is optimized for preventing the slippage.

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We studied the dynamics of a seamless belt in the belt drive system for imaging devices. We focused on the belt skew, which varies with belt drive speed. We assume that the skew is the result of changes in belt tension, slippage between the belt and roller and changes the belt movement direction. Therefore, we developed techniques and measurement devices that visualize the factors. This paper reports on the visualization methods, the measurement devices and availability of the system.

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We observed that skew changed in the belt transfer system of image forming devices, especially at high speed. We measured drive load and belt slippage in the axial direction. We found that slippage in the axial direction was a factor leading to skew. That means that belt skew resulted not only from the kinematics of lead angle change, but also by slippage in the axial direction.

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Electrostatic inkjet phenomena took place when high voltage was applied between an insulative capillary tube filled with ion conductive liquid and a metal plate electrode. Droplet diameter and dropping frequency were controlled by the voltage application. We developed new micro fabrication techniques using commercial etching liquid based on the electrostatic inkjet phenomena. The first technique was a thinning of metal rod. The diameter of the rod was controlled by the time of voltage application between the capillary tube and the metal rod. The other technique was a drilling on a shin metal sheet. Small holes were punctured on the shin sheet. Hole diameter, some 10 μm to some 100 μm was controlled by the amplitude of applied voltage.

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A preliminary investigation has been conducted on the three-dimensional micro fabrication utilizing the electrostatic inkjet phenomena. Suspension which disperses alumina nano particles to water was ejected and printed layer by layer to fabricate three-dimensional structures. We have demonstrated that the square shaped grid, 115μm-width, 140μm-height, was capable to fabricate by the electrostatic inkjet.

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Stability of a droplet hanging from a nozzle in an electric field was examined theoretically to estimate how the stable jet was achieved in the electrostatic inkjet process, which was attractive to the industrial application. The basic equations are the Young-Laplace equation for droplet shape and the Laplace equation for electric field. These equations are coupled and solved by the Finite Element Method. By the initial condition of its shape, a drop could be deformed into different shapes, such as "conical shape", "nipple" or "dog bone" with the increment of non-dimensional electric field. The concentration of electric field around the corner of a nozzle was found to be the cause of this kind of multiple shapes.

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Crown rollers are often used in the flexible media transport mechanism consists of a rubber layered roller and a steel roller. In this paper, the flexible media transport characteristics of crown roller is investigated theoretically. The purpose of this study is to analyze the flexible media transport characteristics such as longitudinal distribution of normal force, nip pressure, traction, and to develop the design method of crown roller that has desired characteristics. First, a numerical analysis method of a contact problem between a rubber-layered roller and a mated steel roller using the results of two dimensional contact analyses was established. Second, two types of crown rollers, i.e. a steel roller with crown shape in its outside radius and a rubber roller with crown shape in its inside radius, were examined. And based on analysis results, a design approach of crown shape which can realize uniform longitudinal distribution of normal force, nip pressure, traction, was proposed. And the flexible media transport characteristicses of crown rollers and the characteristics for error load were shown numerically. Last, designed crown rollers were fabricated and the performances of them were confirmed with experiment.

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Paper wrinkle or crease is generated in the process fixing the toner to the paper. Especially, paper crease is a big trouble of printing process. This paper deals with this paper wrinkle and crease. In the first approach, a experimental apparatus is made and experiments for confirming paper crease are carried out with changing forms of roller. In the second approach, simulation model is composed of a driven rubber roller divided solid elements, a rigid cylindrical shaft and a paper divided shell elements. The simulation is conducted using explicit method by FEM software. Simulation and experiment results are compared and the relationship between roller form and paper wrinkle is discussed. Finally, conditional equation related to paper wrinkle is derived adapting buckling theory of thin plate and the mechanism of paper crease is explained by strain, contact pressure and friction on the contact area of roller and paper.

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Having a highly reliable method to numerically analyze sheet-moving behavior is very important when designing sheet-handling machinery. In this paper, we describe a three-dimensional simulation method we developed that can predict the behavior of sheets in an overlap-type sheet stacking mechanism by means of the finite element code LS-DYNA. The simulation results of the stacking orbit of the sheet head were in good agreement with experimental one. We also analyzed the stacking behavior for 4-folded sheets; and the intervention phenomenon, which also usually occurs in practical stacking processes, was predicted when two or more 4-folded sheets were continuously stacked. We found that this new numerical simulation method is effective for designing sheet-stacking mechanism.

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A letter sorting machine separates pieces of mail one by one from a stack of various types of mail, reads information such as their postcodes and addresses, then stacks and sorts them according to the reading results. Recently, the performance requirements for such machines have become increasingly stringent in overseas markets. In order to meet these requirements, Toshiba has developed a world top-class technology that can process more than 43,000 pieces of mail per hour, employing an air-absorption technique. This technology will facilitate our further expansion into overseas markets.

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This paper introduces self-reproducing structures composed of multiple types of parts. Self reproduction is a kind of self assembly in which the desired structure is obtained automatically from simple parts. Our aim is not to achieve self reproduction by controlling the parts directly, but by controlling their environment, namely passive self-reproduction. It seems to us that one of the most successful examples of self-reproduction is the method used by deoxyribonucleic acid (DNA), that is, semiconservative replication. Hence, we developed self reproducing structures by imitating the semiconservative replication of DNA. The proposed method can handle not only one or two part types, but also more than two part types to create complex structures. We explain the design of the parts used for creating a self-reproducing structure composed of multiple part types. We also show the experimental results of the evaluation of the effectiveness of the design of the parts and of the specific self-reproducing structures. The experimental results show that the proposed method can create self-reproducing structures by controlling only the temperature and disturbance of the environment.

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To investigate the effect of masked UV irradiation (UV patterning) on molecularly thin liquid lubricant films coated over magnetic disk surfaces, distribution of 2-nm-thick functional lubricant films was examined using molecular dynamics simulations in which UV irradiation is modeled by enhancing the polar interaction between lubricant end groups and disk surface. We found that masked UV irradiation induced molecular flow from non-irradiated region to irradiated region, and thereby a concave-convex surface structure in the equilibrium state. We also conformed that the internal kinetic and potential energies of the lubricant films drastically increased immediately after UV irradiation, and then gradually decreased accompanying with the molecular flow.

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Conventional friction force microscopes (FFM) had the disadvantage of low force sensitivity due to mechanical interference between torsion caused by friction force and caused deflection by normal force. We have developed dual-axis micro-mechanical probe. It measures the lateral force by detecting the deflection of the double cantilever and measures the vertical force by the torsion beam. However, the method of detecting the probe lateral deflection has not been established. In this study, we present a new method precisely which detects the probe lateral displacement in order to detect the friction force.

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