In electrical discharge machining (EDM), it is well known that removal rate and surface roughness are improved with ultrasonic vibrated tool. However, it is difficult in an actual machining to keep resonant conditions with a tool electrode of various sizes and materials. In this study, a new supporting method of an ultrasonic transducer and the vibration transmission method of a tool electrode are examined. EDM and abrasive machining were performed with ultrasonic vibrated tool. In the machining of steel plate, the machining speed was improved by five times compared with conventional finish EDM. The tool electrode excited by ultrasonic vibration is also applied to diamond abrasive grinding process for removing carbon layer on insulating ceramics after EDM with an assisting electrode. Mirror surface of silicon nitride ceramics can be achieved through the grinding process.

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This paper deals with a new floating nozzle for suppressing thin blade wear effectively in slitting with minimum quantity of coolant. This nozzle is characterized by its property of maintaining a small clearance between the blade surface and the nozzle tip easily and supplying coolant to the grinding zone effectively by the adhesion of the coolant to the circumferential face and the side faces of the thin blade, thus reducing the coolant flow rate to a large extent. In the experiment of slitting of SKD11 with a WA blade, it is found that the radial wear of the blade in the case of the floating nozzle is about 2/3 of that of a conventional nozzle. The effect of the developed nozzle is also confirmed from the results of slitting of WC with a diamond wheel and of stainless steel (SUS630 in JIS) with a CBN wheel with remarkable reduction of the radial wear to 2/3 and 1/3, respectively. Furthermore, as an application of the method, a new floating nozzle for multi slitting blades is proposed.

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Electro-rheological Gel (ERG) is developed to overcome two defects of Electro-rheological Fluid (ERF); one is sedimentation of ER particles, the other is that the seal structure is needed to apply ERF to machine elements. The developed ERG is composed of ER particles and silicone gel. The ER particles are sustained by the gel component, and thus will not precipitate out, which suppresses the decrease in ER effect associated with precipitation. The ERG shows the wide range of shear stress variation in response to the applied electric field. This high performance of ERG is originated in a different mechanism from the ERFs. To apply the electric field to the ERG, it is necessary to sandwich the ERG between plane-parallel electrodes. However, it is not convenient for the practical use to wire the both of electrodes for high voltage supply. In this study, the one-sided structured electrodes are proposed in order to simplify the structure of the wiring. When the conductive material is used as the opposed plate, the basic characteristics of ERG on one-sided electrodes are evaluated numerically and experimentally. The result shows that ER effect depends on the electrode pattern. Moreover, the yield stress of ERG on one-sided electrodes can be calculated by using the result of electric field analysis and the relation of parallel electrodes between electric field and yield stress.

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This paper describes that nano-scale phenomena in the mechanical removal processing of the nano-sheet by using Atomic Force Microscope (AFM) is clarified and the processing experiment of the nano-sheet using the phenomena is tried. Potassium niobates (K₄Nb₆O₁₇·3H₂O) layerd structures with thickness of 2nm is used as nano-sheet in this study. The processing characteristic at the time of nano-sheet processing is investigated, and the following things becomes clear. Processing becomes easier by weakening united force between nano-sheet surfaces reduces the processing easier, and the control to the thickness direction in 2nm unit is possible by load change. Moreover, the remove phenomena of nano-sheet with thickness of several nm is thought that the brittle-like because of the characteristic of crystal structure. In addition, anisotropy in the direction of 90° existed on the surface of the nano-sheet turns out from the calculation and it is clarified that there is a huge influence in making to high accuracy of the shape and size when processing the nano-sheet. By these processing characteristics of nano-seats, the example of 2.5 dimension processing controlled in each 2nm in direction of depth and straight line groove processing of about 33nm in width can be obtained using these characteristics of nano-sheet. Thus, some kinds of a high precision removal processing is found to be able to achieved.

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This paper deals with the machinability of BN added Steels in end milling. The cutting tests were carried out by end milling carbon steel JIS S45C, S55C and these BN added steels with carbide tool and TiAlN coated carbide tool. Tool wear, cutting temperature, and, surface roughness were measured and discussed. In end milling BN added steel with square end mill, the progress rate of flank wear width was decreased and fracture at corner was suppressed in comparison with that in machining standard steel. In case of ball end mill, flank wear in end milling BN added steels were smaller in comparison with standard steel. In case of S45C, boundary wear was observed, however it was not observed in end milling BN added steel. BN added showed almost the same surface roughness as standard steel. The temperature of flank wear part in turning work based S55C were 50 °C higher in comparison with S45C base work. The temperature of throw away end mill was higher 100°C in comparison with solid square end mill. There were not significant difference between the temperature in end milling standard steel and BN added steels.

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In semiconductor manufacturing, CD-SEM (Critical Dimension-Scanning Electron Microscopy) is widely used as a process monitoring tool. As design rules become more fine and dense, needs for controlling three-dimensional shape in addition to two-dimensional size of the pattern, such as a CD value, have risen for the process monitoring. In this paper, we propose a method for estimating a thickness of photoresist pattern only from a single top-down SEM image. In this method, the relationship between the image features calculated from the top-down SEM image and photoresist thickness is learned beforehand, and the thickness is estimated using the relationship. High throughput can be expected owing to the small number of necessary images, compared to stereovision techniques that require two or more tilt images with different viewpoints. In addition, we propose a method for estimating lithography process parameters that can cause thickness decrease. It is confirmed that the thickness of photoresist pattern (designed thickness 270nm) could be estimated with accuracy of 19.9nm (3σ), which is so small that the method can be applied to photoresist thickness monitoring.

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The measuring system for evaluating the accuracy of a deep hole is developed by using the autocollimation principle. The system consists of a measuring unit and an optical system for light reception. The measuring unit comprises one laser diode, two mirrors, two quarter-wave plates, one polarizing beam splitter, and a feeler. It detects the displacement of a feeler on the basis of the autocollimation principle. The optical system for light reception, which receives the laser beam irradiated from the measuring unit, comprises a plano-convex lens and a CCD camera and receives the laser beam irradiated from the measuring unit. In this study, the evaluation function of various errors of the optical system is derived using ray tracing and their effect on the measuring accuracy is examined. The results show that the measurement error of the deep-hole measuring system due to the misalignment of the optical parts is about ±1 μm and that the detection error of the mirror angle due to the lens aberration used in the optical system for light reception can be reduced to less than 0.003°, which corresponds to the displacement of 0.87 μm of the feeler.

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In recent years, the CMM (Coordinate Measuring Machine) quickly has been spreading in the manufacturing industry. With this phenomenon, the environmental condition and installation site of CMMs has been changed from the temperature control room to the workshop environment and the production line without air conditioning. However, even in severe environment the demand to high accuracy measurements by CMM has been enhancing still more. Therefore, the methods to evaluate and realize the high accuracy measurements by CMM in workshop environment have been investigated. In this paper, we propose the evaluation and correction method of squareness errors using MCG (Machine Checking Gauge). Additionally the performances of CMM in workshop environment and temperature-controlled room are tested and corrected experimentally. From these results, we confirmed the availability of the proposed methods.

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This paper describes a measurement system for the edge radius of a long precision tool. A line-CCD camera is employed to scan the tool edge over the entire tool length. The edge width of the tool at each scanning point is first evaluated from the image of the line-CCD camera. The edge radius is then calculated from the edge width based on the calibration results using pin gauges. A multi-line scanning method is proposed to reduce the defocus errors caused by the out-of-straightness error of the scanning stage. Experimental results have shown that the edge radii over the entire length of a 5100 mm long tool can be evaluated in 30 minutes.

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This paper describes the step climbing analysis of an in-pipe mobile robot using a wheel drive mechanism for a step existing between pipes with different diameters. The wheel mechanism can drive the wheels and also press them against the pipe wall using only a single actuator and a planetary gear drive mechanisms. The step climbing process is analyzed with the systematically calculating forward dynamics of planar mechanisms that considers the elasticity of the wheel. The calculated results were in agreement with the experimental data of the prototype robot, which is 45mm in diameter and 130mm length. The wheel mechanism can climb up steps when the contact positions of the sun gears and the planetary gears are before the contact position of the wheel and the steps.

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This study deals with scheduling problems with consideration of synchronized operations by multiple production resources. Transfer of a material between a machine tool and a conveying device by a human operator is a typical example of the synchronized operations. When the synchronized operations are taken into consideration, it is necessary to check conflicts between the resources before an appropriate job is assigned by Earliest Starting Time rule, which is one of the popular dispatching rules. A new sequence is proposed in the present paper to check the conflicts. Feasible scheduling with the consideration of synchronized operations is realized by combining the proposed sequence with a conventional dispatching rule. Computational scheduling results are shown in order to verify the effectiveness of the selecting sequences proposed here. Computational scheduling is carried out, and the results show that a practical production schedule can be planned without any conflicts by the proposed sequence, despite complex constraints due to the consideration of synchronized operations. Furthermore, a blocked status of the machine tool, the conveying device and the buffer appears on the Gantt chart unlike the conventional scheduling methods.

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Manufactures have paid a great deal of effort to obtain agility in their manufacturing to avoid losing commercial opportunities. To solve these problems, several methodologies for production planning and operating manufacturing systems have been proposed. Additionally, although variety of lot sizing methods has been proposed, most of their objective functions are based on time and quantity criteria. However, the most important criterion is varied dynamically in real manufacturing environment. Product cost is calculated by integrating results of all activities in production processes, so product cost is treated as a comprehensive criterion to evaluate production performance. In this study, we develop a cost evaluate system and it is implemented on a Distributed Virtual Factory (DVF) to realize rational cost based decision makings. The efficiency of product cost as a criterion is discussed through simulation experiments with DVF.

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