This paper shows a development of a novel 3-DOF positioning stage for ultra-precision grinding machine. The stage utilizes three stacked piezoelectric (PZT) actuators to control the orientation errors of the moving part and to improve stiffness. For purpose of eliminating the hysteresis of PZT actuator and improving the property of response, three high positioning sensors (capacitive sensor) are used for the closed loop control and three flexure hinges are designed as guide. Not only the structure of flexure hinge but also the location of each flexure hinge on the moving platform is also elaborately designed in order to provide the sufficient pre-load and minimize the bending deformation of ultra-precision positioning stage. On the basis of static and dynamic model developed, the algorithm for closed loop control is proposed by own. Finally, the experiments have been carried out to evaluate the static and dynamic performance of the stage and the results show that the static and dynamic models proposed are in well agreement with the experiment results and 4nm resolution can be achieved.

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A unique method to calculate both working stiffness and damping coefficient between grinding wheel and workpiece has been adapted to evaluate the grinding condition during grinding process. The relative displacement between wheel axis and workpiece is measured and Fourier transformed to calculate these parameters. This calculation is preceded corresponding to the constant interval of grinding stock removal continuously under the certain grinding condition. The calculated stiffness showed characteristic behavior from the start of grinding process to the end of wheel life. The calculated damping coefficient showed the negative value corresponding to the unstable grinding condition. Further, the relation between the dynamic balance factor and these calculated parameters are evaluated with regard to the grinding stock removal. In this report, the capability of the monitoring method to detect the state of grinding process is evaluated by using the calculated parameters

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This study aims to improve tool life by investigating the effectiveness of the use of high oxygen atmosphere for the reduction of adhesion by generation of oxide. Titanium alloy (Ti-6Al-4V), Inconel 718 and four other kinds of coated carbide end mills were used in this experiment, and the effect of cutting atmosphere on tool wear were investigated by side cutting under the dry cutting condition. From the results obtained, because the adhesion was decreased by the oxidation, the tool life in the high oxygen atmosphere became longest under the dry cutting conditions. Moreover, when the titanium alloy was machined, (Ti, Al)N and TiSiN recorded the highest wear reduction in the high oxygen atmosphere. The smallest wear was recorded by TiBON. It was observed that machining under the high oxygen atmosphere was effective to demonstrate the performance of the coating tool from which lubricity was given by the oxide generation.

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For an accurate estimation method of grinding force generated in deep cut grinding process with ball-end grinding wheel, the grinding force is fundamentally analyzed in this study. This analysis consists of four parts as mentioned below : (1) Relation between the grinding force generated on the ball-end grinding wheel working surface and observed values obtained by tool dynamometer are theoretically made clear. (2) The grinding force distribution is experimentally investigated by the pin grinding test, and the unique grinding force distribution, which is not elucidated yet, is also made clear for the first time. (3) The relation between wheel interference angle and specific grinding force is analyzed by the results from the pin grinding test. (4) The grinding force increasing rate is experimentally investigated by the thin plate grinding ability test. Furthermore, the precision grinding force estimation method, which is essential to investigate the wheel fractured mechanism in deep cut grinding test, is established and also certified it's effectiveness.

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Forming tool coated with CVD diamond film which has excellent performance for wear and friction have been expected to be ideal tools for forming processes. However, the surface of CVD diamond film appears as rather coarse due to crystalline composition, and if it is used as coating material on the tool surface, polishing is required to decrease surface roughness. In this paper, polishing method without abrasive grain assisted by ultrasonic vibration in which generated frictional heat accelerate the reaction between metal and diamond is proposed as polishing method of CVD diamond film and the polishing mechanism is discussed.

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In this study, we designed, fabricated and evaluated a hard X-ray focusing mirror having the performance that the full width at half maximum in the intensity profile of a focused beam is 36 nm at X-ray energy of 15keV. By using wave-optical simulator, the relationship between surface figure error characteristics and deformations of intensity profiles was investigated. Simulation results indicated that figure accuracy of 4 nm (peak-to-valley (PV)) was necessary in spatial wavelength ranges longer than 5 mm to realize the ideal focal size. Focusing on surface figuring in the spatial wavelength ranges, the focusing mirror was fabricated by computer controlled plasma chemical vaporization machining (PCVM) and elastic emission machining (EEM), on the basis of the surface profile obtained by combining two surface profiles, which are measured by mircostitching interferometry (MSI) and relative angle determinable stitching interferomety (RADSI). We carried out line focusing tests on the fabricated mirror at the 1-km-long beamline of SPring-8. A full width at half maximum of 40 nm was achieved in the focal beam profile under the best focusing conditions.

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This paper describes a new diagnosis technique of tool life in diamond turning of coppers. A diamond cutting tool closes generally the useful life by gradually increasing face wear and sudden chipping of the cutting edge. Therefore, the cutting force and acoustic emission (AE) have been analyzed to detect each type of tool wear in turning processes. As a result, it was found that the development of face wear generates the 1/f ^β noise to the cutting force, and the occurrence of chipping releases the AE which has the amplitude distribution spectrum, the scaling exponent of which is less than 2. Tool life tests also showed that these extracted features could be used as the criterion for the judgment of tool life under a variety of cutting conditions.

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This paper deals with a proposal for both the fabrication process of single-crystal silicon-carbide (SiC) thin-films and its application to microstructure. The SiC thin film was synthesized using molecular beam epitaxy, where single crystal SiC layer can be grown on single crystal silicon (Si) substrate. Applying lithography and etching process, microscopic cantilevers were fabricated. Reactive ion etching (RIE) process shaped the outline of the cantilevers. Then, the Si substrate beneath the cantilevers was selectively removed with some types of etching processes to compare the geometrical accuracy. Typical dimensions of the cantilevers were 10μm in length and 30μm in width. The thickness was 180nm that is equal to thickness of the SiC epitaxial layer. The bending test of the cantilevers were also carried out to demonstrate its flexibility.

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A machine tool for cutting human bone to assist the total hip and knee joint replacement has been introduced for the surgical operation in the hospital. However, both cortical and cancellous bones are anisotropic material, and it is difficult to cover all the characteristics. Therefore, it is hoped that the machining phenomenon and performance are acquired in the micro order. The authors have experimented cut surface roughness using bone cutting robot, and micro cutting under SEM and microscope using pig cortical bone. And, from he view of anisotropic material, the measurements of the cutting force and the dynamic observation of the cutting chip generation were done. As the result, a clear relationship between the bone structure and the cutting force variation was recognized from the waveform of the cutting force. In the 2-dimensional micro cutting, the specific cutting force depends on the undeformed cutting chip thickness and the tool rake angle. And it is desirable that the tool rake angle is larger for the surgery of arthroplasty.

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In the laser scribing of glass a thermal stress is introduced into a glass plate by means of a CO₂ laser irradiation. The glass plate is then rapidly cooled down immediately after the irradiation. For the purpose of theoretical clarification of the factors ruling the scribable condition and the crack depth, scribable conditions were acquired in laser irradiation experiments using a soda-lime glass plate having a thickness of 0.7 mm. Furthermore, the crack depth and the crack profile were observed for various values of the distance between the heating area and the cooling area. On the basis of the scribable conditions obtained from the experiments, a thermal elasticity analysis was conducted by a finite element method, allowing the following findings to be obtained. The scribable condition can be estimated from the maximum surface tensile stress in the cooling area and the maximum surface temperature. The crack depth in laser scribing depends on the surface tensile stress in the cooling area and the compressive stress field immediately under the area.

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Until now, the relationship between output force distribution and muscular strength in human limbs has been discussed under the theoretical back ground of the coordination of bi-articular muscles and mono-articular muscles. The difference of approach by muscle coordinate system and approach by joint coordinate system was clarified. And, the approach by muscle coordinate system was advocated. In the present study, the details were examined for the application of this approach to the fields based on body mechanics such as sport or rehabilitation. The change of the output force distribution and muscular strength by two kinds of muscular training of leg extension and leg curl exercise were verified experimentally. The relationship between output force distribution and muscular strength under approach by muscle coordinate system was more clarified. The effect of exercise was verified by standing broad jump and standing vertical jump. This is sufficiently useful for the preparation of precise exercise menu or precise evaluation of exercise effect.

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This paper proposes a new algorithm for fitting a Loop subdivision surface to dense sample points. Our fitting algorithm uses marching cubes and shrink-wrapping to fit the initial control mesh to the points measured from objects. It uses quasi-interpolation to quickly calculate the positions of initial control points from subdivision limit points and uses QEM- and curvature-based mesh simplification to preserve feature boundaries of the minute fillet regions so as to accurately fit to the feature edges. The effectiveness of our fitting algorithm was verified in reverse engineering of broad range of engineering mock-ups such as housings of a handheld wireless communicator, a cellphone, and a turbine blade. The resulting initial control mesh of the subdivision surface that was fit to over 10⁶-point cloud had about several thousand of vertices with approximately 10^-3 mean normalized fitting error.

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An image processing technique of beam-tilt angle calibration for critical dimension scanning electron microscope (CD-SEM) was proposed. In the technique the pyramid-shaped crystal sample was used as calibrator and the beam-tilt angle was estimated with the geometrical variety of the sample images. Evaluation for 40 sample images indicated that deviation of estimated beam-tilt angles was 0.13 degree (3 sigma). The technique achieved high precision and quantitative estimation for the beam-tilt angle, and will be applied for semi-conductor process control by the beam-tilt images.

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A 3-D roughness shape can be extracted by applying a 2-D Gaussian filter to 3-D measurement data to deduct the thus obtained 3-D waviness surface data from the measurement data. However, 8000×8000 measurement data, for example, requires a filter large enough to handle 1600×1600 data, meaning that several hours of processing time are needed. In addition, an end effect, namely ringing that occurs at a data end is also a big problem. As a way of solving these two problems, i.e. long processing time and the end effect, use of a spline filter is proposed. However, since it has a different transmission characteristic from that of a Gaussian filter, it will create a directional characteristic problem : filtering results differ depending on the calculation sequences in terms of x and y directions. If these four problems of processing time, end effect, transmission characteristic, and directional characteristic can be all solved, then a conventional Gaussian filter can be completely replaced with a new low-pass filter. This paper proposes to solve the above four problems the low-pass filter using the basic method of adopting a small-sized 12×12 filter, called a G-spline filter, to thinned-out data obtained by down-sampling of measurement data in the frequency domain.

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The turbo molecular pump using the magnetic bearing has been widely used due to its excellent characteristics such as the contamination-free and the maintenance-free. The pumps are generally mounted on the precision apparatus as vacuum equipment. Then it is necessary to preserve the small vibration level. However, although the vibration level of TMP is negligible small, the structure having the TMPs vibrates itself and then the quality of producing materials is degraded. To overcome the vibration problem, this paper proposes that the TMP can be applied as a vibration suppression unit. Firstly, the control structure of TMP on the market is shown and the vibration suppression scheme is clarified. Secondly, it is shown that the bending vibration can be suppressed by driving the TMP attached to the vibration beam. Finally, the motional mode control scheme is shown, and both 1st and 2nd bending vibration modes are simultaneously suppressed.

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