This paper presents a new method for adapting the existing manufacturing system for a requirement change, such as the change of a required motion task, by modifying its kinematic structure from the viewpoint of the degrees of freedom of the end effecter of the mechanism. In a previous report, the authors formulated the kinematic structure and motion task using Lie algebra. In this report, using these representations and their inclusion relations, the authors propose a method for evaluating the reusability of a kinematic structure for a newly specified motion task, and then propose a method for reconfiguring the mechanism in Lie algebra according to the result of the reusability evaluation. Finally, in order to evaluate the usefulness of the proposed method, it is applied to a kinematic design example of a mechanism.

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Preparing tissue sections for light microscopy is absolutely necessary in pathology. This process, however, is still mainly performed manually. Preparing many samples from a large number of specimens requires great skills. Additionally, it is very difficult to maintain predetermined accuracy of the procedure. To solve these problems, we propose a new prototype machine for automatic sample preparations. We developed the machine for automatically mounting sections on the object glass by using static electricity. The principle of this method is based on electrostatically charging the surface of a paraffin block. And, the section is gathered with the insulation tape while sectioning the specimen. After sectioning the block, the section remains adhered to the insulation tape by electrostatic force. Subsequently, the section is transferred to the object glass by being pressed on that by which water is dropped. Moreover, we developed 'Pulling Angle Control Mechanism' to section the specimen. It is a very effective method that the condition when we section the specimen can be freely changed. A new experimental machine has equipped this mechanism. In the use of these methods, it is possible to take out excellent sections on conventional object glass more than before.

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In deformation changes including step-like discontinuities, techniques using a laser beam of single wavelength cannot measure the deformation amounts. Because the deformation changes between successively captured specklegrams would be larger than the wavelength of the laser. We have developed the technique that can measure large deformation changes including step-like discontinuities by using two laser beams of different wavelengths. In an optical system, optical fibers are used to ensure the same optical-path differences between the different wavelengths. Phase changes are evaluated in both the wavelengths through all the successively captured specklegrams. From the difference of phase changes between both the wavelengths, large deformation changes can be estimated, but precise deformation changes could not be estimated. Then, phase changes of one of two wavelengths is also utilized to estimate precise and large deformation changes.

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This paper presents a new micro stereolithography technique to fabricate a micro 3D structure rapidly and precisely by using LCD live-motion mask. Exposure through the live-motion mask fabricates each thin layer precisely without scanning. The extremely thin layers are continuously solidified by providing liquid resin synchronized with the mask changes. As a result, a 3D object is fabricated by continuous laminations of these thin layers.
In order to verify the feasibility, we developed LCD micro stereolithography system based on 3D-CAD and performed some experiments. The lateral and depth resolutions reached 3μm and 1μm, respectively. It took only about 7 minutes to fabricate a pyramidal shape consisting of 100 layers. A micro two-step gear with shaft was fabricated precisely and rapidly without assembling. The module of this two-step gear is only 20μm. The number of the tooth is 100 for the large gear and 25 for small one. These results show that our proposed method has possibility of precise micro fabrication in practical use.

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The present report describes the suitable in-situ scan of a laser stylus for point measuring of free surface with a machining center. The attempts were made to improve the reliability of the measuring accuracy using numerical control function of G02 and G03. That is, we proposed a new measuring method that the laser stylus was scanned around a measuring point on the free surface. The experiments were done to measure the ground surfaces and the end-milled ones by this scanning method. As a result, it is clear that there is proper radius to scan a laser stylus according to surface roughness

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The ultraprecision positioning device for nanotechnology has to be small because it is mainly used on several kinds of microscopes. In this study, firstly, a very small displacement sensor with 1 nm resolution is developed to use as a feedback sensor. The sensor that applies an optical diffraction has the advantage of small size and large gap tolerance between the moved gratings and fixed index gratings. Secondly, by use of the above-mentioned sensor, a small ultraprecision positioning device is developed with 1 nm positioning resolution. Its small stage of 60 mm length and 60 mm width is moved by a stepping motor and ball screw for a coarse positioning and then is moved by a PZT for a fine positioning. As a result of repeated step responses, the deviational error of 0.04 nm and the dispersion error of 0.49 nm can be obtained.

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This research aims at realizing the shape measurement of liquid surface of Stereolithogfaphy. The unevenness on a resin liquid surface causes deterioration of accuracy. Although the smoothing device is equipped with Stereorithograhy, there is no good method to measure the unevenness of liquid surface. It is always difficult to make liquid surface smooth. From this reason, this paper proposes a liquid surface shape measuring method. The measuring method uses the total reflection image, which is a grating pattern distorted by the uneven liquid surface. The factors of the measurement error of this method are listed out, and the influence of measurement error on each factor is analyzed by a simulator. Furthermore, the shape with actual uneven surface was measured and measurement accuracy was investigated. From the result of analysis and the measurement, it is applicable to Stereolithography.

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In the cross-breeding to develop a new genotype plant, it is more important to distinguish fertile pollen grains from sterile ones for the research. The genetic feature in the plant is related with the appearance of the pollen. The proposed quantities of shape and pattern on the pollen by the image processing are insufficient for distinction between the former and the latter, since appearance of hybrid pollen grains by the cross-breeding can not be estimated previously. The paper proposes the color index and the color index diagram as a new quantities for the estimation of the pollen grains. The color index shows a quantity of the feature color of the every pollen by using the xy color chromaticity diagram. The color index diagram shows an area of distribution on all of the color indexes. By the color index and the color index diagram, it can be measured that the pollen grains are fertile or sterile as the genetic trends of the plants. In the paper, it is shown that the color index and the color index diagram are more effective to distinguish between fertile and sterile pollen grains in some samples from the new genotype plants.

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A new microwave plasma CVD system for generating diamond is developed and the experiments for synthesizing diamond under higher pressure than atmospheric pressure are carried out. Methane concentration in hydrogen carrier gas and substrate temperatures are optimized as the most important experimental conditions for generating diamond using the CVD system. Experiments in which diamond is synthesized under higher pressure than atmospheric pressure are also carried out, and growth rates and Raman spectra are investigated. Consequently, the growth rate of diamond using this CVD system is 100 micrometers thickness per hour, which is ten times higher than when conventional low pressure CVD systems are used. It is found that the optimal methane concentration exists, which becomes higher as pressure increases. From the experimental results obtained under conditions in which the pressure is varied from 800 hPa to 3000 hPa and the other conditions are maintained at the same values, it is also found that the growth rate of diamond reaches a maximum at 1500 hPa. This result shows that optimization of the other conditions is necessary to obtain the highest growth rate of diamond at 3000 hPa.

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Ultra-small diameter cemented carbide ball end mills have been developed. Tools having a radius of ball nose of 10μm have been manufactured by electrical discharge machining (EDM), because conventional methods cannot be readily applied to microtool fabrication. The spherical shape of the tool cutting part is realized via an electrode wear phenomenon in EDM. Milling of brass using fabricated tools has been performed at 2 μm axial depth of cut and 4 μm pick feed. Although simulation suggests the surface roughness (Rz) in tool feed direction to be 0.05 μm at 100 μm/s feed speed, in actual milling, the surface roughness is 0.42 μm, due to plastic deformation of the workpiece. Investigations indicate that the tool life decreases rapidly when the feed speed or the body length increases above a certain value. The tool life can be improved, especially at low feed speeds, by changing the angle between the two planes that each contain one ball end cutting edge from 180°to 90°.

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Water droplets forms spherical surface due to the surface tension, and changing the size of droplets can vary the radius. In this paper, the availability of a droplet as a lens was investigated by applying for laser processing. Silica glass was used as a workpiece. Defocused ArF excimer laser beam was irradiated to the glass with/without droplets respectively.
As a result, the laser beam could be focused by the droplets and caused cracks inside of the glass not at the surface. Changing the size of the droplets and the wettability of the glass enables to control focal length. Aspheric droplets formed by varying the wettability of the glass surface spatially, can control the laser beam intensity distribution. Many small droplets on the glass surface condensed by cooling enables to reduce the threshold of the laser fluence to process and enhance the processing speed.

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In the context of current industrial needs, such as the improvement of resin-bonded grinding wheels, the authors propose a promising method for fabricating the resin-bonded grinding wheels (the authors named "Resin-Piled wheel", RP wheel) by stereolithography. In this proposal, the photohardenable resin/grain mixture is used to fabricate the resin-bonded grinding wheel. This paper describes some results of fundamental study. First, we revealed the optimum stereolithography conditions by curing tests. Subsequently, we developed the special experimental stereolithography apparatus (SLA), and carried out the fabrication of the 1A1-type wheels and the mounted wheels using this SLA. Furthermore, the grinding tests were performed. The main superiorities of the RP wheel compared to the commercial wheels are as follows, (1) drastically decreasing of fabrication time within 10 min, (2) few coagulation of abrasive grains, (3) better surface roughness with lower wheel wear.

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A new finishing process for metal molds by large-area electron beam irradiation is proposed in this study. In the large-area electron beam irradiation equipment used here, the electron beam with a maximum diameter of 60mm can be used for melting or evaporating metal surface. Experimental results show that the roughness of the irradiated surface becomes smaller with increasing the energy density of beam and the number of irradiation, but excessive energy density and too many irradiations make it a little worse. Under a proper condition, the surface roughness decreases from 6μm to less than 1 μm in just a few minutes. The glossiness of the surface also can be improved very well. By observing the cross section of irradiated surfaces, it is confirmed that the material removal is performed just on the irradiated surface without any resolidified layers. Moreover, the surface roughness after irradiation becomes smaller when the roughness before irradiation is small. Therefore, large-area electron beam irradiation method has a high possibility of high efficient finishing process for metal molds.

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Glass disk substrates of 2.5 inch diameter were polished using two types of epoxy resin plate, which were of intermediate hardness between that of the metal lapping plate and polisher. The polishing characteristics were measured for various experimental conditions, such as the grooving condition, polishing pressure, and loose and/or fixed abrasives. From the experimental results, polishing using a combination of epoxy resin plates and CeO₂ abrasives of average diameter 0.7 μm shows a higher removal rate (MRR > 1.0 μm /min) with good surface roughness (Ra < 1.0 nm), flatness (within 0.3 μm in a diameter), and edge accuracy around the substrate. The higher removal rate was achieved due to an increase in the real micro-contact area between the resin plate and substrate. This can be explained well by the comparatively large elastic deformation of the resin plates, which was simulated with the aid of finite element analysis.

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This paper discusses the grindability of sprayed coatings of tungsten carbide-based cermet. A sprayed coating exhibits weak interparticle cohesion because it is actually a laminate of fine particles. Nevertheless, sprayed coatings can easily be applied to parts that require the coating of large areas. This experiment compared the grindability of sprayed coatings obtained by high velocity oxygen fuel (HVOF) spraying of thermal spray materials varying in the proportion of tungsten carbide and containing different kinds of binding agents (Co, Ni-Co, Ni, or Ni-Cr). Aresinoid diamond grinding wheel was used to grind the surface of the sprayed coatings. The grinding surfaces tended to be rough because they frequently bore microscopic irregularities caused by partial peeling, cracking, or swelling of the sprayed particles. Of the materials tested, coatings of Co-based binding agents with higher proportions of WC provided better ground surface properties.

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This paper deals with the measurement accuracy superior than 0.05-0.1°C for 0-50°C range of the developed data-transmission system. To realize the measurement accuracy best, it is necessary to satisfy several conditions; namely the calibration of the system should be carried out under several different temperatures or more and under sufficiently insulated condition, the output of all channels should be compensated based upon the temperature of electric circuit board and the warm-up operation for electric parts is needed.

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Microlens is a key component in the fields of optical communication, data storage and digital display. Integration of microlenses and optical devices is also required for weight saving, reduction in assembly cost and higher accurate alignment. This paper deals with the development of a novel method to fabricate spherical microlenses and microlens arrays. In this method, microlenses are formed on the surface of acrylate resin which is used as sealing material for the optical devices such as photodetectors, laser diodes, CCD image sensors and so on. Microlenses are fabricated under several conditions, and the influences of process parameters on the dimension of microlenses are investigated. The fabricated microlens and microlens array have the appropriate shape, surface finish and alignment so as to condense light.

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A new method of curved hole processing for cooling jackets of metal molds is proposed. This machining technique is characterized by a self-processing electrode capable of following the shape of the curved hole to be machined. In order to reduce the friction between the electrode and workpiece pointed out in the previous paper, it was attempted to vibrate the electrode. An improved electrode, which increased in hardness at the root side and increased in flexibility at the tip side, was produced and its effect was empirically verified. The experiments clarified that the processing method with electrode vibration was effective for friction reduction and could successfully produce smooth curved holes. In consideration of an application to metal molds, it was found that a change of the turn speed of the electrode as well as a change of the electrolyte pressure can control curvature of curved holes.

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