This paper deals with vibration effect for miniature mechanism assembling. Assemble for miniature mechanism is used in precision mechanics and electronics generally. An optical fiber array is an optical communication device that consists of multi-core optical fibers and a V-grooved substrate. As the demand for optical fiber arrays has increased significantly, it needs the mass production of optical fiber arrays. For automatic assemble of optical fiber array, a fiber must be put in a precise position of V-groove. The friction of an optical fiber with the V-groove's slope prevents precise positioning. Therefore vibration application is effective in order to reduce the friction of an optical fiber with the V-groove's slope. The vibration application was possible to influence the positioning of fiber with V-groove substrate.

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Making the surface of insulation layer flat using CMP (Chemical Mechanical Polishing) is important for producing IC (Integrated Circuit). Although simulations of CMP have been carried out using various methods to clarify the effect of working conditions, behavior of slurry including polished debris has not been clarified yet. In this paper, simulation of CMP is carried out using SPH (Smoothed Particle Hydrodynamics) in which slurry including polished debris can be handled. The behavior of polishing slurry and pad damage caused by the slurry are analyzed for various strength of interaction between polished debris and for various ditches on a polishing pad. It is shown that polished debris become bigger in the neighborhood of polished surface when interaction between polished debris becomes stronger. On the other hand, when interaction becomes weaker on ditches become shallower, the number of small polished debris that circulate within the ditches increases. The polishing pad is damaged rapidly for strong interaction between debris and for shallow ditches on a polishing pad.

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This study describes to finish the curved surfaces in hardened steels (JIS: SKD11, etc.) with (Al, Ti) N-coated ball nose end-mill. Two kinds of cutter locations are used; scanning line cutting and contour line cutting, for finishing the curved surface of hardened steel. In the present paper, the cylindrical surfaces machined by a ball nose end-mill are investigated. As a result, in scanning line machining, an irregular luster (striped pattern) peculiar to the machining work surface was caused by a profile error of ball nose. In addition, a new method was also proposed to estimate the peculiar striped pattern which could be judged from observation of the machined surface using Makyoh-topographic images.

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This paper describes the presumption of lubrication phenomenon in steel cutting process with copper sulfate (CuSO₄) by molecular orbital method. A popular theory states copper causes lubrication in the steel cutting process with copper sulfate. But an argument to the popular one occurs in our experiments of this study. We carry out a chemical element analysis with EPMA (Electron Probe Micro Analysis) and ESCA (Electron Spectroscopy for Chemical Analysis) to the cutting interface made by the experiments in order to estimate a friction state in the interface. And we calculate electronic state by molecular orbital method in order to estimate the frictional strength. As a result, Mechanism of lubrication of copper sulfate doesn't depend on the copper sulfate as the popular theory but depends on the sulfur element moved from upper surface of workpiece into the interface.

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By using ultra-high pressure and speed polishing, the research aims to develop the ultra-high removal rate polishing technique under the ultra-smoothness polishing of aluminum type of magnetic disk substrate. In the report, the change of removal rate with polishing process using colloidal silica abrasives is experimentally examined and polisher life is discussed. Polishing pressure and speed range from 10kPa to 60kPa and from 1.5m/s to 9m/s, respectively. The polishing pressure of 10kPa and polishing speed of 1.5m/s are near the highest region of polishing conditions used generally at present. The polisher used is a suede-type one consisted of single nap layer. In the polishing conditions used generally at present, the removal rate decreases through polishing process of four steps. Second step is the steady polishing process. Fourth step is the process of polisher life in which the removal rate is extremely small. First step and third step are the transient polishing processes from initial polishing process to steady state process and from steady state process to polisher life. In the ultra-high pressure and speed polishing, on the other hand, the third and fourth step can not be found for long polishing process. The change of removal rate with polishing process has little influence on surface smoothness.

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The study deals with the development of micro axial-flow pump by means of 5-axis control ultraprecision machining technology. The demand for producing 3-D micro parts is clearly growing year by year. A micro pump for an implantable blood pump is a typical example of important micro mechanical system applicable to bio-related fields. 5-axis control ultraprecision machining technology is suitable for machining such a complicated shape. In the study, a micro inducer is treated as a target shape. Our own 3-D CAD/CAM system for 5-axis control machining is developed in order to manufacture micro inducers, considering the setting error of cutting tool, which is extremely difficult to remove and affects the machining accuracy. In the cutting experiment with the 5-axis control ultraprecision machining center and the diamond ball end mill of 0.2 mm in radius, the micro axial-flow pump is successfully created, whose material is oxgen-free copper. The result of performance test shows that the created inducer functions as a micro axial-flow pump.

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A new ultrasonic elliptical vibration tool is developed in the present research to realize sculptured surface machining of die steel by applying “elliptical vibration cutting”. The new vibration tool is designed to have three degree-of-freedom (3 DOF), so that it is suitable to machine the three-dimensional sculptured surfaces. The 3 DOF ultrasonic elliptical vibration tool generates an arbitrary ultrasonic elliptical vibration in the three-dimensional space by combining two directional bending vibrations and a longitudinal vibration. It is excited by piezoelectric actuators at 34.4 kHz, which is an average resonant frequency of the three vibrations. The developed vibration tool is attached to the 4 axis precision machine tool developed in the previous report, and mirror surfaces of hardened steel are obtained successfully by the proposed method.

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In terms of the realization for high accurate and effective machining of complicated shape having under cut shape and free formed surface, five axis controlled machine tools become indispensable because they have any tool position and attitude to avoid the collision between machine tool elements and work piece. These five axis machine tools have a technical problem as machining accuracy, which is inferior to that of three axis NC machine tools. In order to estimate the motion accuracy of NC machine tools, various kinds of certificate methods like circular cone cutting test prescribed with NAS and DBB method using the circular motion have been developed and standardized. These methods are mainly used for the motion testing of three axis NC machine tools and therefore new method and measuring equipment for five axis NC machine tools are needed. This study aims at developing the motion accuracy measurement system which can measure various kinds of motions like linier motion, circular motion and continuous curved motion under simultaneous five axis controlling and establishing the compensate method of tool motion. Consideration is added from the viewpoint of motion accuracy using measurement system developed in this report in case simultaneous five axes control motion command value from CL data. About object machine tool, it is reported about framing of the most suitable NC data.

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A measuring system of drill geometry parameters has been proposed in the previous report. The system is based on laser displacement sensor, slide and rotary tables. Different types of errors may occur while collecting the coordinate data of the drill geometry parameters. This paper describes the calibration of the measuring system for estimating grinding parameters and geometry parameters of the drill point. The calibration procedure, calibration method and error correction method are proposed in this paper. To develop a practical apparatus of the measurement system all setup errors have been considered and measured and as the database they are preserved. Thus, the error can be corrected automatically according to the measuring position. The measured data agrees well with the designed values. It was proved theoretically that the accuracy achieved by this method is enough for the measurement of the drill.

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We propose a non-contact method for measuring the film thickness of various materials based on the photothermal effect. It involves irradiating a film surface with a nanosecond laser pulse. Various kinds of elastic waves that have a maximum frequency of several hundred MHz are excited by the photothermal effect. However, only those elastic waves which are dependent on the film thickness are sustained in the film, as a result of the resonance phenomena that occur between boundary surfaces having acoustic impedance. The film thickness can be calculated from the detected resonance frequency. Previously, we established a non-contact measurement technique which can measure the thickness of a single-layer film. In this report, we describe a measurement technique for measuring the thickness of a multilayer film. There are three kinds of modes excited by resonance. The frequencies of these resonance modes depend on the differences between the relative acoustic impedances of the materials in the film. We were able to measure the thickness of the layers in a multilayer film by analyzing these resonance modes in each layer. This was done by selecting the frequency analysis window for which the resonant wave was stable.

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The influence in which the precision of time delay gives the spectrum on terahertz time domain spectroscopy is reported. The precision of time delay is proportional to the positional accuracy of the motorized translation stage which gives time delay. The experimental result confirms that positional error of the stage increases the spectral noise and it also lowers the repeatability of the spectrum. The positional accuracy of the stage affects the higher frequency region of the spectrum greatly. Those indicate that the positional accuracy is an important parameter to show the reliability of terahertz time domain spectroscopy. The evaluation of the influence of the positional accuracy of the stage on the spectrum by computer simulation is suggested. The method to lower the spectral noise and to improve in the repeatability of the spectrum by measuring the positional error with the signal waveform simultaneously and correcting the signal waveform is proposed. It is shown by an experiment as well as computer simulation that this method is effective.

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In calibration of roundness measuring instruments, self-calibration techniques are used to obtain a form error component of the workpiece (Hemisphere) and a systematic rotation error component of the probe simultaneously. The multistep method is one of the commonly used self-calibration methods. However, the multistep method has following two problems. One of these problems is that the multistep method can not separate the probe rotation error from the form error of hemisphere completely; unseparated components remain in both error components as forms of Fourier components determined by the step number. The other problem is that the multistep method can not detect the Fourier components whose orders are integral multiple of the number of steps, therefore the smaller the number of steps are the more unseparated Fourier components remain in the calibrated values.
In this research, two analysis techniques are proposed. One is a complete error separation technique which is able to separate the probe rotation error and the hemisphere form error completely. The other is the phase combination method by which calibration results equivalent to higher number of steps can be derived by combining two results of the complete error separation technique with different smaller number of steps. By using these two analysis procedures, unused performance of multistep method is fully exploited, and the uncertainty may be considered to reach to a sub-nanometer level because the separation is now complete. These techniques only use simple algebraic equations without using a Fourier transform. These techniques are considered to be applicable not only to the roundness measurement but also to the evaluation of the form profile which can be expressed by the 360° closure systems such as various circular forms.

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The linear motor driving mechanism is adopted for positioning mechanism of the machine tools to realize high speed and precise positioning, because of frictionless and no backlash. When the table of machine tools is driven at high speed, two or more linear motors are used for the same axis to obtain the high thrust power. In case of using more linear motors, however, the position of the table changes because the thrust force of each linear motor doesn't become the same. In addition, this causes to generate micro vibration and to change the velocity of each linear motor due to yawing around the center of gravity. In this study, the imaginary motor control method was proposed with three linear motors for driving table to control the position of the gravity, the vibration and yawing. From the results of simulation and the experiments, it is confirmed that the proposed method can control the position of the gravity, the vibration and yawing independently.

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This paper presents mechanical and temperature analyses and walking experimental results of a developed 8-leg walking robot using thin shape memory alloy (SMA) wires as actuators. Two SMA wires are strung between a leg and the robot body. As an SMA wire pulls the leg in the horizontal direction and another wire pulls the leg in the vertical direction, the leg moves in an elliptical orbit by sending the wires sine- and cosine-curve electric currents. The maximum step of the leg is about 8 mm and the walking velocity is 6 mm/s. Temperature-time variation of the SMA wire was analyzed, applying the law of the conservation of energy. Then, the walking step and velocity of the robot were calculated from the experimental result of the hysteresis loop between the strain and temperature. The calculated results were in good agreement with the experimental results.

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Worker's skill is important in manufacturing industry especially mold one, because workers design and manufacture products with comprehending characteristic of material and product specification. Mold industry such as plastic injection molding goes ahead with automation lately. Educating and taking over worker's skill are difficult by automated equipments because of black boxed job. The troubles might happen that manufacturing of high accuracy and productivity mold and all-new mold are impossible, if worker's skill are not enough in the industries. Consequently, this paper proposes the innovative proposal for operational software of production system to upgrade worker's skill. Upgrading worker's skill is supported by the method of configuring and providing operational software based on worker's thought model timely. The method shows the CAM-software adapting to each beginner's skill or middle-worker's skill, respectively. As a result, the validity of the method is proved from the aspect of productivity and processing accuracy in the experiments.

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