A new manufacturing process with abrasive water jet is proposed to fabricate micro channels or dimples on glass. Masks having exposed areas cover the surface so that the covered areas cannot be machined. Because the width of the exposed areas is much smaller than the diameter of the jet nozzle, tapers are made in the cross section of the masks so that abrasive slurry can reach the exposed surface. Abrasive slurry is mixed with water supplied by a low-pressure pump in a water jet nozzle. When abrasive water flows onto the surface vertically between the taper-shaped masks, stagnation is made right under the nozzle. Because the flow velocity is low in stagnation, brittle fracture does not happen on the machined surface. The vertical flow also changes to the horizontal direction at a high velocity out of the stagnation. Abrasive particles, therefore, machine the surface in the horizontal direction at a high velocity. The jet nozzle moves back and forth for several times along the exposed area. A V-shaped groove, which is a depth of 2.5µm and a width of 20µm, can be machined on the surface of fused silica. A micro fabrication machine is made to fabricate micro grooves at the specified positions and angles. It is shown that the machine works well to make micro patterns on the surface in some examples. A machining example proves that the machined shape can be predicted with computational fluid dynamics

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Hairline finishing, which leaves a detailed continuous line pattern on the surface of a metal, is being used widely in industrial products for its ornamental and functional effects. However, the evaluation of their quality is done, in many cases, sensuously and subjectively though visual inspection by skilled workers because evaluation is based on geometrical continuity and regularity of the line pattern and other kinds of information. This research aims at developing a way to evaluate hairline finished surfaces objectively and quantitatively by the image processing. First, the pictures of hairline finished surfaces were taken using a CCD camera, and the textural analysis was carried out by estimating the gray level co-occurrence matrix and the gray level run length matrix. This textural analysis is effective because there was a clear difference in textural features between the pictures judged as good and the pictures judged as bad. In consideration of these results, the evaluation system using the neural network was developed.

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This paper deals with truing/dressing of a high accuracy spherical wheel to be used by the Parallel Grinding Method. The parallel grinding method is an arc-envelope grinding method in which a grinding wheel with an arc-shaped cross-section is used to generate an aspherical profile. Therefore, the influence of the setting error of a spherical wheel in Parallel Grinding Method and the wheel setting error in truing by CG system were investigated. Furthermore, it clarified about the relation between dressing conditions and the number of cutting edges. As a result, a highly accurate sphered wheel was achieved.

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Continuous process of welding and heat treatment using a laser is proposed. The process begins with the welding stage where the laser irradiates in pulse mode at the optimized power so as to minimize the heat affected zone (HAZ). Next, to improve the mechanical characteristics of the HAZ. The temperature during the heat treatment is controlled by the laser power, the scanning speed, and the number of laser scans. Therefore this is a continuous process completed in a short time. This process is applied in the joining of dissimilar materials (spheroidal graphite cast iron and ferritic stainless steel) that are used in the exhaust components of automobile engines. Observations of the weld specimen with a microscope showed the formation of high carbon hardened martensite in the HAZ of the cast iron. The ratio of the welding joint strength to the spheroidal graphite cast iron strength was 69% (343MPa). Then using the heat treatment, the martensite was transformed into troosetite. After the continuous processing (1 laser scan) the joint strength became 82% (408MPa). The trial weld of the car engine exhaust part passed the thermal fatigue test of the engine bench test.

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Using the atmospheric pressure plasma chemical vapor deposition (CVD) technique, further investigations were performed to improve the structure of the hydrogenated amorphous Si_1-xC_x(a-Si_1-xC_x:H) films deposited at extremely high rates. The films were prepared on Si(001) wafers at atmospheric pressure in a very high frequency (VHF) plasma of gas mixtures containing He, H₂, SiH₄ and CH₄. Structure (C-H and Si-H bond densities) and composition of the a-Si_1-xC_x:H films were studied as functions of VHF power, CH₄/SiH₄ ratio and the substrate temperature by infrared (IR) absorption spectroscopy and Auger electron spectroscopy. Surface morphology of the films was observed by scanning electron microscope (SEM). It was implied that particles generated in gas phase deteriorated the film morphology and caused excessive incorporation of hydrogen atoms in the film. Both suppressing particle formation in gas phase and elimination of excessive hydrogen atoms bonded to C and Si atoms at the film-growing surface were important factors to enhance Si-C network formation. As a result of optimising the deposition parameters, a stoichiometric a-SiC:H film could be deposited at the substrate temperature of 550°C.

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The purpose of this study is to propose a composite packing technique for damping characteristic improvement on the structure packed with balls. In this paper, the damping characteristic of the composite packing structures is experimentally investigated. First, the effects of composite ball size and material on damping characteristic are examined in the case of composite packing of different ball size and composite packing of different ball material. The experiments show that the damping characteristics are markedly affected by the composite ball size and material, and it is confirmed that the damping capacity is effectively improved. Secondly, the effect of the viscoelastic material hardness and packed ball size are shown in the case of composite packing of the viscoelastic material and the steel balls. It is found that dramatic improvement in damping capacity is achieved by the composite packing of the soft viscoelastic material and the large steel balls. The generation of the noise by the collision of balls is not induced in such structures. Moreover, some considerations on the damping capacity generation in the composite packing structures are carried out.

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High speed end milling of nickel base supper alloy Inconel 718 with (Ti, Al)N coated cemented carbide tool was conducted in the cutting speed range of 175∼300m/min. Cutting temperature was also measured by tool-work thermocouple method. The temperature increased in power law of cutting speed, feed rate, and radial depth of cut as seen in milling of Ti-6Al-4V alloy. Temperature in milling of Inconel 718 was about 150∼200°C higher than that in milling the titanium alloy. The wear rate depended largely on the temperature, and it had a local maximum value at the temperature of 640°C because of the adhesive wear. The rate increased rapidly when the temperature was over 680°C because of the thermal wear, while the rate was low and stable when the temperature was below about 600°C because of abrasive wear. There were the optimal conditions that achieved both long tool life and the maximum removal volume. The conditions, however, were limited in extremely narrow range of the temperature about 680°C. The wear rate in milling of Inconel 718 was ten times higher than that of Ti-6Al-4V alloy.

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This paper presents a scheme to estimate cutting forces in end milling without using any additional sensors. An external disturbance can be estimated by monitoring the armature current in servo motors. It is, however, often subject to high friction on guideways, particularly in a stationary direction, which makes it difficult to estimate the disturbance in an accurate and stable manner. On the other hand, the armature current in a spindle motor is less affected by the friction, although only the tangential component of cutting force can be estimated. This paper proposes an estimation scheme of all the components of cutting force by geometrically combining force vectors given by servo motor and spindle motor currents. The accuracy and practical applicability of the proposed scheme are validated by experimental case studies, where the cutting force control for end milling processes is implemented based on the proposed estimation scheme.

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An oscillation-speed-control-type sequential grinding and polishing machine has been developed to achieve a site flatness better than 90nm per 25-mm square except for 2mm adjacent to the edge of a 12-inch silicon wafer. The machine allows a wafer to be polished after grinding without removal from the machine. This paper describes the creation of a grinding profile, a solution to the problem of flatness degradation, and the optimum polishing conditions to obtain good flatness. The moving path of the grinding wheel is accurately transferred to the ground wafer surface except its center portion, where the profile becomes concave due to high cutting path density of the grinding wheel. Good flatness was achieved with a simple inclination adjustment method that involves hanging a weight from the grinding head or using a very low infeed rate to decrease the grinding force. The ground wafer was polished at the optimum oscillation speed and a super-high flatness of less than 0.1µm over the entire surface was achieved. In addition, this result was roughly consistent with the simulation result.

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This paper deals with the optical telemeter system of strain-gauge output in rotating object. Bridge circuit composed of strain-gauges is connected to an amplifier and the output of amplifier is A/D converted according to the control series generated by a one-chip micro-controller, and the A/D result of serial data series is fed to LED on rotating object and sent as the optical data series. The optical data series is received by PD on stationary head, and the serial PD output is converted to parallel datum and inputted to personal computer. Tensile force acting on the sensing plate based upon the centrifugal force due to the spindle rotation is measured by the strain-gauge and the optical telemeter system. Theoretical tensile force is calculated. It is confirmed that the measured force coincides well with the theoretical force. This system has the function of quick-input of known-strain.

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Simultaneous 6-axis control machining with a non-rotational tool, which can create sharp corner shapes, is not necessarily efficient due to the small depth of cut and the low feed speed. Though the application of simultaneous 5-axis control machining with rotational tools is advantageous in terms of the machining efficiency, the cutting remaining peculiar to the rotational tool take place near the corner part. Therefore, using two machining methods together enables the efficient machining of sharp corner shapes. In the previous paper, we showed the high efficiency of our original machining method of character line using 5-axis and 6-axis control. As the industrial products have various kinds of the corner shape pattern besides the character line, however, the proposed machining method could not cope with all corner patterns. This paper describes the classification of corner shapes at the end of the character line and the generation method of cutting point data for machining of all patterns using 5-axis and 6-axis control.

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A MUSIC (MUltiple Slgnal Classification) is super resolution and high accuracy measurement algorithm for location finding of the signal sources of the received signals using the array sensors. However, it is known that the location finding error remarkably increases when the array receiver has amplitude and phase deviations between sensors coming and estimating the signal sources from far field environment. This paper describes the MUSIC characteristics for the near field sound sources when the receiver has sensor deviations. And also, this paper investigates compensated preprocessing algorithm for estimating and decreasing sensor deviations. For confirming the algorithm characteristics, the computer and experimental simulation are done, and it is clear the MUSIC and preprocessing algorithm are enable to properly estimate the location of sound source and sensors deviations.

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Because the visually impaired desire to know not only color of the 1 point but also whole color on the object, we developed a color discrimination system by the presentation of the sound which enable the blind to recognize the color and its change. While the blind scans the surface of a target object with this system, it continuously makes sound corresponding to surface colors. The problem is the mapping between color and sound for the blind to learn easily and to get the color condition shortly. In this paper, we propose the Shepard Tone Method (STM) and the Trio Ensemble Method (TEM) as this mapping.

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In order to survive severe global competition in manufacturing industries, there is a growing importance in manufacturing systems' efficient operation. To maintain the efficient operation, continuous improvement activities, Kaizen activities, are necessary. The current Kaizen activities solve only individual problems of machines and workplaces, but these activities cannot always bring the best solution as the whole manufacturing system performance. From the viewpoint of the system performance, it is necessary to use manufacturing system simulation to determine the order of priority of Kaizen ideas. This study proposes the integration system that is able to update the simulation model using the data of Manufacturing Execution System (MES) in order to make the simulation model efficiently. To realize the integration between MES and simulator, XML is used to define the format of the common data. For practical use, the user interface shows the values of the exchanged data and the original data, so that the user can check the values of both exchanged data and the original one, and choose which to refer to. To confirm the effectiveness of this simulation environment, a test case is tried out. This study is done as the MISSION project funded by IMS program.

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