This paper presents the method by which the change of abrasive grit size and the silicon particle size of multiwire saw slurry are measured quantitatively. The mechanism of wire saw slicing is discussed from a microscopic viewpoint based on the measurement results ; (1) GC abrasives and silicon particles are separated each other by the suction filtering and chemical treatment technique. Their size distributions are measured by Coulter counter with 10% accuracy. (2) After slicing a 400mm-diameter ingot with 200mm in length, the consumed abrasives are estimated to be approx. 7.0% in mass and 2.4% in number. On the other hand, silicon particles generated by the slicing range in 1-10μ m diameter. (3) It is presumed as one of microscopic models of wire saw slicing that an indentation, a rolling and a scratching are actions of abrasives, and an effect of the scratching grows as the wire running speed increases.

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In servo motor drive system, maximum current supplied to the motor must be limited by the servo amplifier for preventing the trouble of motor. So a saturation element must be included in the servo motor drive system. Overshoot such as windup phenomena sometimes occurs in the nonlinear control system that includes the saturation element. Here, countermeasure for the overshoot must be done. Countermeasures for the overshoot like windup about the velocity control system that include the saturation element in the control loop have already researched in the past. On the contrary, an countermeasure for the overshoot about the position control system with saturation element in the control loop has just presented in this paper. Countermeasures for the overshoot about the velocity control system cannot be applied to the overshoot about the position control system. The method for preventing the overshoot for the position control system is shown such as limiting the maximum velocity of motor. It is found that this method presented in this study confirms the effect of preventing an overshoot.

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An analytical model to predict motion accuracy of hydrostatic feed tables and a corrective lapping algorithm to improve their accuracy, which were proposed in the previous paper, are verified experimentally in the present research. Ahydrostatic feed table is developed, which has a single-sided guide in the vertical direction and a double-sided guide in the horizontal direction. Profiles of its guide rails are measured with a previously developed apparatus, which has a measuring accuracy of ± 0.03 μm. The averaging effect of oil film in the multiple pad table is clarified analytically by introducing 'motion error transfer function', which relates the motion error of the table with the rail profiles at each special fiequency. The motion errors of the table are simulated by the proposed analytical model in accordance with the measured profiles and the calculated motion error transfer function, and it is confirmed that the motion errors simulated in the vertical and horizontal directions are all in good agreement with the errors measured with a laser interferometer. Furthermore, the corrective lapping algorithm developed in the previous research is also verified experimentally by utilizing the developed feed table with a stroke of 145 mm, and straight motion accuracy of 0.07 pun and 1.42 arcsec is achieved for the double-sided guide, and 0.13 pin and 1.40 aresec for the single-sided guide after the corrective lapping.

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Statistical distribution of the effective rake angle of abrasive grains is obtained by applying kinematically admissible velocity fields to a huge number of three-dimensional micro-cutting processes with abrasive grains which randomly differ in the normal rake angle, inclination angle and cutting edge angles. Based on this distribution, which has a peak around the effective rake angle of - 5 degree, thermo-elastic-plastic FEM analyses of orthogonal cutting processes are conducted for rake angle - 60 to 30 degrees. Other cutting conditions are also widely changed to investigate the influence of cutting speed, rake angle, undeformed chip thickness and tool material on grinding characteristics. Simulated results show a critical undeformed chip thickness under which chip forms with great difficulty. The critical value decreases as cutting speed or rake angle increases. This may result in better grinding performances and ground surface integrity in high or ultra-high speed grinding.

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Recently, ultrashort-pulse lasers with high peak power have been developed, and their application to the materials processing is expected for a tool of precision microfabrication. During surface generation process with laser ablation, a shock wave propagates inside the material and lattice defects such as dislocations are generated beneath the surface. Lattice defects influence the quality or accuracy of materials processing, therefore it is important for laser precision microfabrication to elucidate the generation mechanism of them. In this paper, laser shock phenomena of metal were analyzed using the modified molecular dynamics method, which has been developed by Ohmura and Fukumoto. Main results obtained are summarized as follows: (1) The shock wave induced by the Gaussian beam irradiation propagates radially from the surface to the interior. (2) A lot of dislocations are generated at the solid-liquid interface by the propagation of shock wave. (3) Some dislocations are moved instantaneously with the velocity of longitudinal wave when the shock wave passes, and their velocity is not larger than one of transverse velocity after the shock wave has passed.

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The mist process using small amount of cutting oil has been the most effective cutting method in interrupted cutting process, such as end milling. In continuous cutting, however, the chips always cover the cutting edge of the cutting tools. The feasibility of mist process as an effective method has never been proved previously. Therefore, the purpose of this study is to investigate the potential application of mist process in continuous cutting. In particular, the so-called oil-water combined mist process method was studied. This process is to supply an oil-water combined mist that includes water and cutting oil. The heat produced in cutting process had been removed from cutting edge with the vaporization of the water mist and the oil mist lubricated the cutting edge of the cutting tool simultaneously. Therefore, the application of the oil-water combined mist provided better cooling and lubricating capability in the mist process. The experimental results show that the oil-water combined mist process is effective for continuous cutting processes, especially in the situation that the lubricant is difficult to reach the cutting edge. This process also improves the quality of the machining surface, reduces the wear off of cutting tools and provides a cleaner manufacturing environment than traditional continuous cutting processes.

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Drill breakage is one of the major problems in small hole drilling. Therefore, real time breakage prediction can improve production reliability remarkably. To predict drill breakage, this paper describes an in-process non-contact measurement of small cutting torque acting on micro drill. A thin-walled elastic cylinder is divided into three parts by two parallel slits. The top cylinder is connected to the middle with a small beam and the middle cylinder is also connected the bottom with a small beam at the opposite side of the top. The middle cylinder is push out to radial direction when torque is applied at the end of the top or bottom cylinder. By measuring this radial eccentricity of the middle cylinder with non-contact displacement sensor, this torque can be detected. Torque detection spindle, which has the thin-walled elastic cylinder and two displacement sensors at the drill chuck, was developed. It is proved that small cutting torque less than 0.1Ncm can be measured by this technique through small hole drilling on some materials at high speed.

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In order to develop a new ultra-precision and ultra-clean machining method, electrochemical machining in ultrapure water was performed. A new method for increasing OH^- ion in ultrapure water using catalytic reaction that dissociates the water molecules into H⁺ and OH ion was proposed. As examples, ion-exchange membrane and fabric were used. Also first-principles molecular-dynamic simulations of interaction between water molecule and sulfonic acid function of ion-exchange material in order to analyze the mechanism of dissociation process of water molecule were performed. In the case of using sulfonated graft-polymerized polyethylene fabric, over 6A/cm² current density was obtained which suggests that the density of OH ion in ultrapure water increases to about one million times larger than in the case of without using catalytic reaction. As a result of machining experiments, etching were occurred for Cu, Mo and Fe anode under the condition of less than 2A/cm² of current density. Thus the possibility of electrochemical machining in ultrapure water for industrial application was confirmed.

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For the recycling of CVD (chemical vapor deposition) diamond coated cutting tools, a mechanical method, where old films were partly ground and re-coated, has been conducted. However, because of some problems it is not considered as an effective method. In order to overcome these difficulties, the authors have recently proposed a new technique for de-coating the diamond coatings on tools completly by combustion in a high temperature. This article clarifies the mechanism of the de-coating method, and proposes the treatment method for tools with different coating lengths. The examples of treatment conditions for de-coating obtained from the test results are reported in this paper. The durability cutting tests were performed with the regenerated tools. Finally the effectiveness of this technique was verified by the cutting tests.

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It has been previously reported that the output force distribution at the wrist demonstrated in a hexagonal shape, and the conventional joint coordinate system discussed with only joint torque could not explain human output force characteristics. The results obtained in the present experiments were:1) Characteristics of the hexagonal output force distribution made it possible to estimate the hexagonal shape from only four measured output points. 2) All estimated hexagonal shapes of the subjects employed showed sufficient reproducibility and reliability, and could represent the output force characteristics of each subject. 3) Individual functional effective muscular strengths could be evaluated from the hexagonal output force distribution. And, this technique can be applied effectively to the field of rehabilitation or sport where the evaluation of muscle strength is needed.

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In the present research a human stance posture control system and a dynamical model for its action are described. The stance of a subject is based on a number of internal body functions, and is arrived at through the combination of nerve centers connecting receptor organs such as inner ear vestibules, sight and kinesthesia, with effectors such as muscles and bones, and a number of functions such as the peripheral nervous system. Accordingly, a subject's stance can be regarded as a sort of barometer for comprehensively evaluating the entire body. The stability from a control engineering standpoint and the health condition were discussed from the model and several subjects aged from 20 to 60 years old. It was found from experiments that the "fluctuation" of a body swaying was a key factor in evaluating health conditions of a stance posture control system. Further there was no obvious relationship between the stability and the health condition in this system.

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A new method to drive an ultraprecision XYθ table is developed by utilizing piezoelectric actuators, which is based on the principle of 'Walking Drive'. The table is supported and driven directly by nine pairs of the feed and support actuators. The device does not require any conventional guides, and it is free from undesirable friction. Displacement patterns of the feed and support actuators are predetermined in the proposed method, and they are given to the actuators in real time in accordance with an arbitrary command path. A prototype ultraprecision XYθ table and a simple open loop controller are developed based on the method utilizing the predetermined displacement patterns. A 6-axis position measuring system is also developed with laser interferometers and capacitance type gap sensors. Driving experiments are carried out by utilizing the positioning and measuring systems, and the feasibility of the proposed method is verified experimentally.

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Micro-waviness has been defined in the hard disk industry as the amplitude component just between roughness and waviness wavelength. The disk micro-waviness may cause microscopic fluctuation in the head/disk spacing and so a special attention is paid to the relationship between the two properties. From an engineering standpoint that the spacing fluctuation might result in amplitude modulation of head readout signal, a number of hard disks that have various micro-waviness components were prepared in order to investigate the correlation between the disk micro-waviness and the head readout signal. The experimental analysis showed that the average amplitude of disk micro-waviness is well correlated to the amplitude modulation of the head readout signal in a certain wavelength band. A method to estimate the longer wavelength limit of micro-waviness as well as readout signal was also presented.

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In this study, an experiment to detect the small particles adhering to a wafer and the crystal originated particles (COPs) existing in the wafer, whose diameters are approximately 0.1μm, is carried out successfully. An experiment to separate COPs from detected particles is also carried out. Both particles and COPs are detected when an Ar-ion laser is illuminated perpendicularly downward onto the wafer, and the obliquely scattered light is detected using a photomultiplier tube No. 1. Only particles are detected when a YAG laser is illuminated obliquely with an incident angle of 77° and the light scattered perpendicularly upward is detected using a photomultiplier tube No. 2. On the basis of the two detected signals, the particles and COPs can be recognized independently. The experiment was conducted using two types of wafers. One is a wafer made by a Czochralski (CZ) method, which is known as a wafer with COPs, and the other is a wafer made by a floating zone (FZ) method, which is known as a non-COP wafer. COPs are detected on the CZ wafer but not on the FZ wafer. On the basis of this experimental result, it is experimentally verified that COPs can be detected by this detection method.

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In this paper, a method of repeatedly direct kinematics is introduced. By using this method, a flowchart serving for the solution of inverse kinematical problem of an articulated robot arm is investigated. The performance of the flowchart is analyzed in a robot arm whose inverse kinematical answers cannot be directly obtained in formula because of the existence of an offset in its wrist. In the flowchart, because the position error and the posture error are evaluated separately the computing efficiency becomes very high. In addition, another flowchart dealing with the plural answers of a robot hand with the same position and posture is put forward. The solution of the plural answers makes it possible for a robot arm to avoid the angular limitations of its joints or to bypass the obstacles while working.

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A new calibration system for up to a middle size CMM is developed. The spatial coordinate comparison method is realized for the practical system by applying direct coordinate comparison between the reference CMM and the object one. Following to the first report describing the basic concept and its primary evaluation result, the second report studies a noble method to analyze statistically estimated reliability of the calibration result. The experimentally obtained parametric error on a real CMM is assessed by comparing it with that obtained by the laser interferometer. The assessment result shows that the proposed calibration system estimates the parametric error with in the statistically predicted reliability range. Meeting demand to recent calibration technology, the practical calibration system with indication capability of its uncertainty is realized.

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In the study of pollen for plant cross breeding, it is considered that the shape of pollen and the genetic features of its plant are related. In order to explain this relationship, it is necessary to observe pollen. However, such observed parameters have not been quantitatively defined. This paper proposes the shape and pattern quantities of pollen which are measured by image processing. Two types of pollen grains of cultivated species and their hybrid ones by cross breeding are measured based on the proposed quantities. The results show that the proposed quantities reflect the genetic features of the pollen.

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The normalized correlation matching is a typical image processing method for industrial applications. However, the normalized correlation matching requires a large computational cost because all pixels in a template image are used for the matching process. This paper proposes a method to extract partial block areas and pixels in the template image that are effective for the image matching using the two-stage genetic algorithm. The experimental results show that the number of pixels for the image matching was reduced to 7.8% by the 1st stage genetic algorithm and reduced to 1.5% by the 2nd stage genetic algorithm. The processing time for the image matching was also reduced from 9.78 second to 0.87 second by the proposed method.

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Vibroscanning (VS) method can be a valuable tool for profile measurement of high aspect ratio micro parts such as micro holes. Its limitation still arises from the measurement principle, which assumes sample's electric conductivity. To overcome the limitation, a new VS sensor, which combines a VS probe and an off-the-shelf quartz tuning fork, has been developed. In the development, specific problems in applying the long thin VS probe to the quartz tuning fork were clarified. Thereafter, the new sensor construction and assembly process is proposed. The sensor's theoretical model was introduced and the model's validity and limitation were examined through experiments. Sample measurements were carried out after incorporating the new VS sensor into the measurement system, which has XYZ-axis mechanical stages and a PZT micro positioner. Measurement repeatability of better than ±0.2μm was confirmed in block gauge surface measurements. Three-dimensional rendering of roughness gauge surface measurement was successfully obtained, which clearly showed the surface topology. These results prove the usefulness of the new VS sensor, which has overcome the limitation of the conventional VS method.

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This paper describes development of an efficient measuring method of 3-dimensional edge profile with high accuracy for free form surface. A new method is proposed for measurement of 3-D edge profile by means of optical ring images. 3-D profile sensor based on optical ring images has more advantage than the others because it detects as not a light spot but a ring image of the reflected light from a target point. The changes of optical ring image intensity occur in the edge. The differences between the intensities of ring images in the ordinary plane and the edge are represented by cross correlation coefficient, which is used as measuring parameter to detect the 3-D edge profile of a master model. In automatic experiments, first the characteristic area which may include the edge is extracted by rough measurement, second the measuring path of the sensor adapted to the edge profile is decided in the characteristic area. Finally, the edge positions are detected by using the cross correlation coefficients obtained by fine measurement along the measuring path and the 3-D edge profiles are estimated.

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