The characteristics of the machined surface is generally considerably poorer than the grinded surface due to affected layer by a plastic deformation occurring around the cutting edge. A work-affected layer is generated due to plastic deformation occurring in the vicinity of the cutting edge on the finished surface with metal cutting processes. The objective of this study is to evaluate the machined surface characteristics on reverse finishing 0.45%C carbon steel focusing on the direction of finishing with respect to the roughing direction. Orthogonal dry cutting tests by the application of reverse finishing were performed to investigate the difference from that obtained by the same direction finishing from the viewpoints of hardness, cutting force, residual stress. It was suggested that there is an appropriate combination with the depth of cut on finishing and the depth of work-affected layer caused by roughing in order to obtain the effect of reverse finishing. Effect of rake angle on hardness was smaller as rake angle becomes larger. The cutting force was smaller in reverse finishing as the rake angle becomes larger. Residual stress after reverse finishing was larger than that in same direction finishing. FEM simulation setup capable of reproducing reverse finishing was created.

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For pathological diagnosis, it is necessary to slice tissues embedded in paraffin and prepare a slide glass of the section. Slicing is a fine cutting process with a depth of cut with a few micrometers, and there are many unclear points about the mechanism and the distortion inside the thin sections. Therefore, this study aims to investigate the thinning mechanism in detail using a paraffin block. In this report, we report the effect of cutting conditions on the cutting data and morphology of thin sections measured using the tissue slicer we have developed.

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Built-up Layer (BUL), produced by accumulating workpiece on the tool rake face, has the tool protective effect and the smaller depth of overcutting during cutting of metal material. The main objective of this paper is to clarify the formation mechanism of BUL with different cutting tools during cutting of titanium alloy. To clarify the influences of coating characteristics on BUL’s formation mechanism, dry cuttings of Ti-6Al-4V with three different cutting tools (uncoated, PVD coated, CVD coated carbide tools) were conducted. From the results, as expected, it is confirmed that BUL can form on the different tools’rake face and it can protect the tool rake face from wear to some extent. The coating characteristics have the great influences on the BUL formation process and the size of BUL. Meanwhile BUL plays a great role on the fall-off of coating. Finally, the ability of BUL to increase the cutting tool performance was also analyzed.

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A novel cutting process is presented to machine helical polygon shapes in the through holes with double rotations kinematics. A boring bar and a workpiece are controlled simultaneously to rotate at n : (n-1) rate of the spindles. When the tool is fed with changing the ratio a little, a helical polygon is machined in the hole. A kinematic model is established to simulate and control the polygon shapes in the presented process. The cutting tests were conducted to validate the helical polygon machining with the kinematic simulation. The flank face of the tool was ground to control the clearance of the tool from the inner surface in the cutting tests. In the presented cutting process, the helical polygon shapes are machined in the through holes at high machining rates. The polygon can also be controlled by the ratio of the tool and the workpiece with a boring bar.

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In the present paper, we focus on machined surface quality and accuracy when creating a curved surface in a five axis controlled machining center. It is well known that it is difficult to maintain high surface quality when generating a curved surface shape with five-axis controlled end milling. If multiple axes are moved simultaneously, synchronization error will occur and quality of the surface will deteriorate. We proposed a novel method to reduce the synchronization error of the machine tool in order to improve the quality of the machined surface by keeping a constant feed speed vector at end-milling point with feed axes and a rotary axis motion controlling. As a result, it is demonstrated that a proposed method is effective to improve the machined surface quality and accuracy due to synchronization error of machine tool.

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In the present paper, we focus on cutting trace shape control of machined surface by radius end-mill based on estimation of internal servo information. According to servo information, we monitor the variation of the feed speed and spindle speed under a cyclic cutting operation with a five axis controlled machining center. Then, we discuss a programming method to control cutting trace shape accurately. As a result, it was found that the spindle speed information greatly affects the prediction accuracy of cutting trace shape.

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In this report, it is aimed to clarify the cutting characteristics of pre-hardened steel used for plastic mold with barrel type end mill in order to improve its machining efficiency. In this paper, the effect of tool feed speed, pick feed, depth of cut with a barrel type end mill on cutting characteristics such as surface roughness and residual stress were studied. In addition, a simulation of the machined surface generation with the barrel type end mill was compared with the actual machined surface. Roughness of the machined surface does not become the ideal cusp height, it is greatly influenced by the runout of the tool and the roughness of the cutting edge.

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This paper describes the effect of the spindle speed on the tool wear in small taper end milling. The small taper end mill has geometry of two flutes and the point angle of 60°. The cutting tests of pre-hardened steel were carried out under the condition of spindle speed from 20000 to 80000 min⁻¹. The flank wear and the cutting force were investigated. As a result, the maximum width of flank wear decreased with an increase in the spindle speed. It was found that the spindle speed was effective in reducing the flank wear.

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The paper discusses surface profiles in milling with structured tool and the cutter axis inclination. An analytical model is presented to simulate the surface profiles for the tool edge shape, the cutting parameters and the cutter axis inclination. Because the surface profiles are controlled in the simulation, the optimum cutting parameters are determined to reduce the surface roughness. The cutting tests were conducted to measure the surface profiles, where microscale nicks were fabricated on polycrystalline diamond edges in laser processing. The presented surface profile model is validated in comparison between the simulated and the measured surface roughnesses. The surface finish can be improved in milling with the cutter axis inclination in the optimum cutting parameters.

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In this study, the water soluble cutting fluid including the fine bubbles was applied to the cutting with end mill. The milling experiments was carried out with the range of cutting speed from 40 to 160 m/min in order to investigate the effect of the fine-bubble coolant on the tool wear in end milling of the carbon steel. As a result, the tool wear was suppressed by using the fine-bubble coolant comparing with the conventional coolant when the cutting speed was 100 m/min. There was no distinct difference in other condition of cutting speed.

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It is studied to cut in the atmosphere as a method of dry condition without using oil. In some cases a reduction in cutting force and flank wear rate was observed by controlling the atmosphere. In the previous study, the reaction products at the interface between the tool and the workpiece were analyzed by XPS and EPMA on the rake face of the tool, the chip surface, and the surface of the workpiece for cutting the carbon steel in a CO₂ atmosphere. In this study, elemental analysis by EPMA was performed on tool flank, and the influence of the CO₂ atmosphere on the cutting condition was investigated.

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Chatter stability analysis has been mainly studied under the constant cutting depth conditions. It is insufficient for milling complex shape including die and mold. The paper presents NC milling simulation of chatter stability for complex shape with arbitrary cutting depth conditions. It calculates quantitative indicator of chatter stability for each tool path, visualizes it, and modifies NC programs to avoid chatter vibrations. The simulation results are in good agreement with the machined surface in pocket milling and chatter vibrations are avoided.

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Current, research for environmental conservation measures is being performed in many fields. It’s the same in fields of cutting. As one of measures, dry and semi-dry machining is picking up that because hardly used oil. But, deep drilling is used large amounts of oil. For reduction of cutting oil, it is important to reduce force applied to the tool and lower cutting heat. So our research aims to develop a new cutting mechanism that reduces the force on drilling. In this research, we conducted basic experiments to reduce force applied to the tool. It is designed and developed a cutting mechanism with a rotation axis perpendicular to the tool axis.

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This study deals with cutting phenomena in micro end-milling of hardened die steels. We have reported that cutting phenomena becomes unstable because end cutting edge of right hand helical tool is damaged early in shoulder cutting. Therefore, we prepared left hand helical tool experimentally to complete processing by improving the strength of end cutting edge. In this paper, to clear influence of angle of left hand helical tool with right hand cut on cutting phenomena in micro end-milling, cutting experiments were carried out with evaluating cutting force, quantity of unstock-removal, machining error, and machine surface by comparing with standard right hand helical tool.

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In this study, we developed motion reproduction system to automate skilled work by using an industrial robot. First, sets of position and posture of the moving tool in the operation are traced by using a 6DOF electromagnetic motion tracking system. Next, unnecessary points are removed from the obtained data points, and the robot program is generated by converting the remaining points into the robot coordinate system. Finally, the industrial robot conducts the operation using the generated program. In this paper, we propose the method of path generation for this system, and verify the usefulness of the system through experiments applying the system to a calligraphy operation.

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In this research, we suggest the catalog-mining method which means applying data-mining method to micro-drill catalogs.We regard the catalogs as mine which includes the knowledge of micro-drilling plenty. Data-mining method is one of the analytical methods to discover the valuable information from a mass of data and commonly used in the undeveloped field of study. In this paper, we considered the tendency of cutting conditions by using the non-hierarchical clustering for the database of micro drill catalogs.

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In this research, we try to construct a system to support non - expert 's cutting condition determination using machine learning method. We have constructed a system that derives cutting conditions from the shape parameters of the tool and the hardness of the workpiece by learning based on the recommended cutting conditions described in the tool catalog by the random forest method. In this section, we report on the cutting condition prediction system which can add information on the coating of the tool and can predict more accurately. In this paper, it was found that the elimination of the outlier which was the subject in the construction of the cutting condition prediction system using the random forest can not be improved by expanding the database (by the method of taking in other company's tool catalog data). It was confirmed that the cause of the outlier was not the lack of the number of data points but the lack of information contained in the database, specifically, the lack of information on the coating.

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In this report, in order to improve the motion accuracy of the robot, compare the servo information of the joint of the robot with the measurement result by the DBB and check the tendency of the operation. As a result, it was found that the robot does not operate correctly as the torque value applied to the joint is larger. Then, it was found that applying some kind of correction to the command at that time is a method leading to improved operation accuracy.

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In this research, by focusing on the joint torque acting on the robot, we propose a method to determine the arrangement of the robot based on a criterion different from the workspace of the robot and examined the usefulness of the method. When two industrial robots perform cooperative motion, it is possible to determine the arrangement of robots based on the workspace. However, when determining the arrangement of the robot based on the torque output by the joint of the robot, it is considered that the robot is arranged at a position different from that based on the working range. For this reason, we focus on the joint torque of the robot and propose a method to determine the arrangement of two compact industrial robots that perform cooperative operation and examine its usefulness. We also examine the usefulness of reducing the load on joints using link aid springs. Considering that a position with a high value of the torque margin map changes by using a spring, consider the motor torque for each joint focusing on factors that improve the torque margin.

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In recent years, the use of humanoid robots has spread and begins to penetrate into daily life. Because it is assumed that humanoid robots work in an environment closer to people, in this report the humanoid robot can achieve work by efficiently using tools and double arms according to such environment and situation aim. Using musical saws as instruments, we aim for realization of tuning control.

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In recent years, high precision control of plates such as 5 axis control machining centers and parallel mechanisms is required. Therefore, in order to make these motion control highly accurate, it is necessary to measure the synchronous motion accuracy of the turning two axes of the plate, and there is a method using a high accuracy gyro sensor for a measurement method. However, this sensor is not on site. Therefore, in this paper, I propose a method to diagnose synchronous accuracy from the orbit of the rolling ball on the plate gripped by a dual arm robot.

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In order to efficiently machine complex parts, the authors have been proposed workpiece shapes during a rough machining operation using topology optimization. However, the operation planning has not been considered adequately. Therefore, as the first step, a determination method of cutting sequence is proposed to create the optimal workpiece shapes. In the method, the cutting sequence is allocated according to the average value of design variables that are obtained at the calculation process of topology optimization. A case study to machine a complicated shape is conducted, and it is found that the proposed method is useful to determine cutting sequence during a rough machining operation.

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We have developed an innovative stirring technology (electric field stirring technology (EST)) that enables stirring without contact by applying electric field abrasive grain control technology. In the previous study, we reported the characteristics of the EST and the shape of the electrode for efficient EST. In this study, the effect of stirring by EST was investigated. Using fluorescently labeled antibody, efficient diffusion and rapid antigen - antibody reaction were examined by microscopic observation and measurement using flow cytometer, respectively. As a result, it was found from the microscope observation that EST increased the antibody moving velocity by about 22 times compared to static condition. Furthermore, from the measurement results using flow cytometer, it was found that the reaction was accelerated 6 to 10 times by using miniaturization and electric field stirring. From these results, we have experimentally clarified the stirring effect.

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This present study describes an application of photocatalytic effect and atomic diffusion bonding to transfer-printing of Au thin-film. A photocatalytic effect of TiO₂-coated stamp decomposes a polystyrene thin-film located under a Au thin-film, so that the Au thin-film is easily transfer-printed on a substrate. It is also demonstrated that atomic diffusion bonding enables a Au thin-film to be transfer-printed on a stamp with pre-coated Au at room temperature. These proposed methods are effective for an improvement of shape accuracy in transfer-printing.

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Micro/nano machining is useful for efficient manufacturing of a micro channel/groove structures on the surface of hard/brittle materials. In this report, the effect of the rake angle on micro/nano machinig characteristics of soda glass and sapphire. It was found that cutting mode of sodaglass changes from ductile mode macining to ploughing mode when the rake angle becomes smaller than -30 degree. However, such mode change did not occur in sapphire machining. Furthermore, specific cutting force of sapphire was influenced by crystalline anisotropy, but its influence depends on the rake angle.

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It was known that the voltage application to silver-doped glass produced silver nanowires in glass substrate. Thus, we conducted the voltage application to gold-doped glass for the gold precipitation in glass. As a result, it was found that large cracks were formed in glass substrate and the crack surfaces were covered with thin gold films. These behaviors were not observed in silver precipitation process, therefore, the gold precipitation mechanism was quite different to that of silver case. In this study, we conducted experiments for several combinations of glass substrates (soda-lime and borosilicate glasses) and dopant materials (gold, aluminum and platinum) to clarify the mechanisms of crack and metal film formations. However, these phenomena were confirmed only in a case using gold film and soda-lime glass.

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In the discharge surface modification method, the electrode material is transferred and deposited on the workpiece by using the compacted electrode or the sintered compact electrode. In this method, the electrode material can be transferred to the mating material at a high degree. On the other hand, there are many problems such as the electrode tool manufacturing and discharge power supply circuit being special. For this reason, it is difficult to use a normal electrical discharge machine as it is. Therefore, in this research, the discharge surface modification method using a general electrical discharge machine is studied. For electrical discharge machining, using commercially available metallic materials, consider conditions such as electrode polarity, long pulse width, the rotational speed of the electrode tool, rotational direction and so on. We investigate the influence of these on the surface modification of the base material.

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In this study, curved hole drilling with small-diameter using a suspended ball electrode into practical materials such as aluminum alloy and cemented carbide are discussed for wide application of this method. In order to stabilize the drilling performance of small-diameter holes, small vibration is applied to the workpiece during the process. As a result, by the workpiece vibration, a hole with small-diameter of about 5.0mm can be achieved using a smaller ball electrode.

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Removal machining cannot generally fabricate a hole on the inside wall of another hole. In other words, removal machining has the limitation for its fabricatable hole shape. To overcome the limitation, our research group has developed the devices which can fabricate such holes. The devices developed in the previous studies could machine a hole of 3.1 mm in inner diameter inside another hole of 21 mm in inner diameter, and could expand the inner diameter of the hole to 15.4 mm. However, the hole with inner diameter less than 3.1 mm cannot be machined. Therefore, this study has developed a new device which can machine such holes with small inner diameter. The basic experiment proves that the new device has the ability to machine the holes.

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In EDM (electrical discharge machining), it is known that a carbon layer is formed by EDM to reduce wear of the electrode. Using a high speed video camera equipped with a high magnification optical system, we observed the material removal process during single discharge during carbon layer formation conditions. In addition, using a laser beam as illumination, an observation system employing a bandpass filter that allowed only a specific wavelength to pass through it was constructed. From these observation results, the mechanism by which carbon adheres to the machined surface was estimated.

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In recent years, new usage of Wire Electric Discharge Machining(WEDM) is expected for rough machining of difficult-to-cut materials such as aircraft parts. Therefore, we are developing new WEDM based on multi-axis control process. So, a new machine tool for multi-axis controlled WEDM process has been developed. The machine tool has 2-axis tilt and rotary tables and it can change the wire posture against workpiece surface. However, it is difficult to plan the path and the posture of wire avoiding the interference with the workpiece while continuously changing the posture. Thus, we propose a new planning method. This method is realized while solving the difficult problem.

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In wire electrical discharge machining, debris tends to stagnate around the wire electrode, since the machined kerf is narrow, secondary discharges often occur, and discharges easily concentrate on the same location, which leads to unstable machining performance, such as wire breakage, low machining rate and low shape accuracy. Thus, better exclusion of debris and bubbles from the machined kerf is very important to obtain stable electrical discharges and high machining accuracy. Conventionally, the debris exclusion from the gap has been carried out by jet flushing of working fluid from upper and lower nozzles. This study aims to propose new jet flushing methods for high-performance wire EDM characteristics by using computational fluid dynamics (CFD) analysis. In this paper, a nozzle jet flushing method with a fine insert following behind the wire electrode, is newly proposed. As results, it is found that debris exclusion can be improved by the insert nozzle flushing method, because of its straightening effect of working fluid flow around the wire electrode. It is also confirmed that the wire EDM characteristics can be improved practically by using the insert nozzle flushing method.

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In a large-area electron beam (EB) irradiation method, uniformly high energy EB can be obtained without focusing the beam. Then, the large-area EB can be used for melting and evaporating the metal surface instantly. It was clarified that the surface functions such as wear resistance and corrosion resistance of metal molds steel could be also improved by formation of modified layer on the surface after melting and resolidification of the surface. On the other hand, the workpiece surface was slightly removed by evaporating the surface. Then, control of the modified layer and removal thickness is effective to maintain the surface function. However, it is difficult to measure the thickness of removal and modified layer under a variety of EB conditions in the experiment. Therefore, it is important to predict change in the thickness of removal and modified layer in large-area EB Irradiation. In this study, influence of the EB irradiation conditions on the removal and modified layer thickness for workpiece, which has different magnetic property, are experimentally investigated. Variations of the removal thickness for the workpiece with different magnetic property of workpiece can be precisely predicted by using electron track analysis and unsteady heat conduction analysis.

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The Niobium- Titanium alloy (Nb-Ti alloy) is composed two elements, niobium and titanium, which have extremely low cytotoxicity, and has a Young’s modulus similar to that of human bone. So, it is suitable as an implant material. Although manufacturing and shaping implants requires cutting processes to be performed, there has been no research on the cutting of Nb-Ti alloys, and the processing characteristics of Nb-Ti alloys have not yet been clarified. In the present study, the influences of tool material and cutting speed on tool life were investigated by milling of Nb-Ti alloy using a small ball end mill tool. The results of these investigations indicate that the tool life can be extended by using a diamond-coated too and that a cutting speed of 15 m/s provides the longest tool life.

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This paper deals with the wear behavior progress of the diamond-coated carbide drill when drilling the cemented tungsten carbide. The thrust force and sectional shape of the drilled hole were also evaluated. The diamond-coated carbide drill, which has two flutes, diameter of 1.0 mm, and coating thickness of 20 μm, was used. The diamond coating on the rake face of the drill was flaked immediately after starting drilling, and the thrust force drastically decreased due to generate the sharp cutting edge by flaking coating. The flaking of the diamond coating around corner edge and the margin region were observed, and the shape of the worn drill was clearly transferred to the sectional shape of the drilled hole.

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Nowadays, a monitoring technology has been attracted attention in the factory automation fields regarding IoT (Internet of Things). However, it is difficult to monitor the process information from a round tool during rotating operation in machine tools. We therefore develop a novel tool holder equipped with a wireless communication function to monitor tool temperature and vibration. In the present report, we attempt to measure the tool vibrations in the rotational and radial direction in countersinking process. As a result, we demonstrated that the developed method with a wireless system was effective to estimate and the tool vibration in countersinking processes.

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A cutting process, which is a metal machining method, has a problem with a phenomenon called chatter vibration. When chatter vibration occurs, it is known that a characteristic mark called a chatter mark can be formed on the processed surface. In this paper, image analysis of chatter pattern is performed by 2D discrete Fourier transform, and chatter frequency is estimated. In addition, we propose a method for suppressing chatter vibrations efficiently on site by analysing the chatter patterns on the basis of analysis results.

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Tool management is extremely important to promote mass-producing of micro-scale machine parts. Thus three-dimensional form measurement technique for edge of micro-tools needs to be developed. In this research, we propose a three-dimensional form measurement by detecting fluorescence from cutting fluids on surface of the tools. This technique enables to measure the edge of a tool more precisely and quickly without disturbance of the cutting fluids. To improve the applicability of the proposed measurement method, we detected the fluorescence signal from the water-soluble cutting fluid and measured the sample surface position.

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Rake face temperature in the turning of titanium alloy under cryogenic CO₂ cooling was measured by using an infrared radiation pyrometer with an optical fiber. Translucent alumina was used as cutting tool. In the cutting, infrared rays radiated from the tool-chip contact face and transmitted through the cutting tool was accepted by the optical fiber which was inserted in the tool. The effects of CO₂ cooling on the rake face temperature was investigated.

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In this research, we propose the measurement method for a non-axisymmetric three-dimensional curved surface on CNC lathe. The measurement results is used for the purpose of improving the profile accuracy of a three -dimensional curved surface. In this study, based on the proposed method, we report the results of the shape measurement of the machined workpiece and its evaluated results.

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[in Japanese]

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This study presents a position control method for rack & pinion mechanism with two-motors. In our method, when the control input which is generated by a position controller is large compared with a given offset value, both the two-motors drive the rack gear. On the other hand, when the control input is relatively small, one motor drives the rack gear and the other one pushes the rack gear to opposite direction, in order to cancel the backlash. The experimetal result is shown to confirm that the proposed method can be used for the positioning of the actual rack gear.

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Recently our laboratory has been developing a microsphere diameter measurement method using optical resonances. Thin optical fibers in diameters around 1 micrometer are used for light coupling. In order to increase the measurement accuracy it is necessary to know the exact diameters of the optical fibers. Therefore we proposed an in-process diameter method for micrometer-ordered optical fibers based on light scattering under standing wave illumination. In this report, through theoretical analysis based on Mie theory, it was confirmed that the far-field light distribution changes with different diameters. Then numerical simulations with finite element method were performed, and the numerical results agrees well with theoretical results, which also proves the feasibility of the proposed fundamental measurement principle.

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Distance and shape measurement are very important in manufacturing especially from the point of view of product quality and safety. In particular, laser tracker (LT) has been widely used for measuring the shape of large products such as airplane wings and boat hulls. Laser interferometers are used to measure distance in the LT so far, but it is impossible to measure absolute distance when the laser is obstructed during measurement. Therefore, in this paper, we propose a new LT having an accuracy of 1μm/m using a tandem low coherence interferometer capable of absolute distance measurement. The position or length is determined by measuring the distance between target and reference ball lenses. As a verification of the proposed measurement principle, distance measurement between two ball lenses was performed.

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We have proposed the novel measurement method of a micro-sphere using the whispering gallery mode (WGM) resonance. In this paper, the measurement performances were shown and the measured results were compared with one by scanning electron microscopy (SEM). Diameter measurement technique using WGM resonance has inherently high measurement resolution. As a result of experiments, estimated diameter was able to be obtained of the order of sub-nanometer with standard deviation of 1.8 nm. The measured diameter was in good agreement with the SEM below 100 nm. As a future work, more detail analysis for measurement uncertainty is necessary.

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This study investigates the vibration isolation effect of rubber sheets under machine bed supports in a vertical type machining center. It is known that the stiffness and dumping of the machine bed supports influence the dynamic characteristics of the machining center, and the rubber sheets are often applied under the machine bed supports to isolates the vibrations. However, the vibration isolation effect of the rubber sheets have not been clarified up to now. In this study, rubber sheets with two kinds of thickness are installed under the machine bed supports of a small vertical type machining center. Frequency responses and motion trajectories are compared with and without rubber sheets. As the results, it is confirmed that the rubber sheets significantly influence the frequency response of the machining center, and the vibration on the motion trajectories can be suppressed by installing the rubber sheets. In addition, cutting tests are also carried out with and without rubber sheets. As the results, it is founded that the difference of thickness of the rubber sheets have different vibration isolation effect in the cutting.

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Appearance quality of the products is an important issue especially in the molds, dies and designed surfaces. However, the geometrical shape error of machined surface and the appearance quality are not identical due to human visual characteristics. Previous studies had clarified that the derivative of normal vector of machined surface is related to the appearance quality. In the previous work, it had been developed that a method to detect the visible un-demanded glitches by calculating the derivative of normal vector of motion trajectory or measured shape of machined surfaces. In this study, a software tool based on the evaluation method is developed. The developed tool is applied to actual motion trajectories and it is confirmed that the developed tool can expect the visible glitches due to the motion errors.

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Recently, a volumetric accuracy for three linear axes was defined as term of multi-axes motion in ISO 230-1. In three axis machining centers, the error motions of linear axes have been checked in compliance with ISO 10791-1 and -4 for a long time. However, the relationship between the measured error motions of linear axis and the volumetric accuracy hasn’t become clear. In this report, the positional deviations of lattice points within entire working volume of machining center were measured by laser interferometer. And the positional deviations were estimated by using a mathematical model in consideration of measurement coordinate systems and the tested linear error motions. As the results, the estimated positional deviations corresponded reasonably well with the measured deviations in a small machining center.

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In this research, a contactless loading device that can excite the rotating spindle was utilized to measure the dynamic compliance of a spindle system. Direct compliance and cross compliance were measured for the spindle of a three-axis machining center, and the influence of the spindle rotation on the compliance was evaluated. The natural frequency shift and the change in damping were observed in both of direct and cross compliances.

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In recent years, the miniaturization and densification of the semiconductor package printed wiring boards (PWBs) have been demanded by the miniaturization and multi-functionalization of electronic equipment based on development of IT. For their realization, downsizing of PWBs’ micro-holes and fabrication of highly dense electrical circuit layers are also important. For high-speed and precision drilling, we proposed a feed driving system withright and leftball screw as a counter balance structure.In a previous study, We solved the high-frequency vibration problem of servo systems¹) . In this report, we clarified various vibration modes of machine tools by the finite element method. As a result, the effectiveness of the damping mechanism for the low frequency mode was confirmed.

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