The electricity rust preventive machining method is proposed to effective prevent the workpiece from rusting in the cylindrical grinding only with water. The workpiece as a cathode is preserved from rusting by supplying the electric current through the water. This method leads to the ecology machining because the water without extreme pressure agents, mineral oils and the like is used as the machining fluid. Therefore, this method saves much work for a treatment of used machining fluid. Main conclusions obtained are as follows: (1) The effective prevention from rusting for 1 hour can be achieved by the electricity rust preventive machining method in cylindrical grinding. (2) The effective rust prevention conditions of electric supplying time and current are experimentally decided in cylindrical grinding and a very few electric power is necessary for rust prevention. (3) The supply current for the rust prevention increases with increasing the voltage, the nozzle-workpiece clearance or the exposed surface area. And the turbulent flow of water interferes with the supply of the current which increased with increasing the water flow rate.

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In the field of semiconductor manufacturing, there has been a strong need for non-contact wafer handling since contact can damage the wafer or can generate particles, which cause defective of semiconductor elements. In the past studies, electrostatic levitation was proposed and applied for 200mm and 300mm wafers. In those studies, three degrees of freedom of a wafer were actively controlled to achieve non-contact levitation. However, it seems difficult to levitate larger wafers using the same control scheme, since larger wafers exhibit considerably large deformation, which would destabilize the control system. In this paper, to realize non-contact levitation of 400mm silicon wafer, distributed on-off control scheme is introduced. The realized system employs 15 pairs of electrode units, for each of which voltage is independently controlled according to the gap. A 400mm silicon wafer was successfully levitated with the proposed system at an air gap length of 0.30mm and 0.40mm.

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An injection mold with inside cooling water channels which are difficult to be made by conventional machining method has been fabricated by using selective laser sintering of steel powders. A box shape work piece has been applied as a test structure. By the cooling inside the corner of the core, the temperature difference in the core surface is reduced and then the dimension accuracy of the work piece is improved compared with the work piece injected in the conventional machined mold with outside cooling channels. The core surface temperature is directly controlled by the cooling water temperature and kept constant at the end of each shot. When the water temperature of the inside channel in the core is assigned properly lower than that of outside channel in the cavity, the warp of the periphery of the box became minimum. Although the heat conductivity of the sintered material is lower than that of mold steel, cooling effect and accuracy improvement are promoted by the combination of cooling channels near the mold surface and adequate cooling temperatures.

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Carbon Nitride (C-N) films which were formed by ion-beam-assisted deposition has a good mechanical performance. The reason is that C-N films have sp² and sp³ bonds and nanotube-like structure. C-N films have better wear property than general DLC films. In order to clarify the mechanical properties further, fracture characteristics and adhesion strength are examined. The fracture patterns were observed by in-situ surface observation system and fracture toughness was measured by nanoindentation in CN and CN/TiN films. The fracture pattern did not watch in CN and CN/TiN films. The value of fracture toughness in CN films is more than in DLC films. Scratch traces were observed by microscopy and AES. In C/TiN films peel occurred among C films and TiN buffer layer and substrate, but in CN/TiN films peel was only observed between TiN and the substrate. The results show, CN films have good fracture characteristics and strong bonding with the TiN films.

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This paper deals with an automatic scraping machine with image recognition system for bearings of surface plate. The automatic scraping machine consists of a large size XYZ stage for machining, a scraper and a CCD camera. The scraper attached on the large size stage just like skilled worker. After manually painting the bearings with red rouge, the image processing system with a colored CCD camera recognizes the bearings from the surface image. By image measurement including the calibration method, black bearings position detecting and tool positioning became possible high-precisely. The scraping level was decided by the area of measured black bearings, and as a result, efficiency improvement of the scraper work and reduction in the scraping error were attempted. For the surface plate finish, the process of automatic scraper work from the pattern scraper work to the recognition scraper work was examined. The positioning accuracy of the scraper using image recognition was 0.3mm. As a result, the surface flatness of the surface plane finished by this scraping machine was 11.6μm which is the same precision of general slide surface.

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This paper proposes a measuring system with visualization based on the high-speed CCD camera for monitoring the behavior of the small-diameter end mill during high-speed milling, in which the characteristics of projection image of the end mills with small-diameter were investigated experimentally. The measurement of an elliptical bar used in stead of an end mill showed that the response delay of the measuring system was very important to affect the image shape, especially in the high speed rotation of the end mill. Also it can be seen that the fluctuation in the system delay disturbs the size and the contour of the end mill in the images, which is characterized by normal distribution. Therefore, the fluctuation is removed by average processing, and the contour or the center of the end mill can be measured precisely.
Further, in order to characterize the cutter behavior from image processing, trials were made on the deflection of the end mill against the static load. When ideas of the equivalent diameter and the length of the end mill are introduced in this analysis, it is shown that the cutter deflection can be related to the static force applied at a cutting edge. As a result, by means of the analysis of the static compliance in the axial direction, the geometrical moment of inertia of the cutting edge part can be sufficiently estimated. And discussion is carried out on the feasibility of the technique for the practical application in monitoring the small-diameter cutting behavior during the high-speed milling process.

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Dentists and dental hygienists remove dental calculus using a cutting tool called dental scaler. The evaluation of sharpness of dental scalers requires skill which depends on sensory examination. The aim of this research is to evaluate the sharpness of scalers objectively. First, an apparatus for taking images of scalers was developed by taking into account the evaluation method of observing the cutting edge reflection used by experts. The scaler to be inspected was fixed on a turn table driven by a stepping motor. The angle of the scaler was changed by the stepping motor and images of the cutting edge of the scaler were taken at various angles by a CCD camera. Next, the area and the length of optical reflection pattern of the cutting edge were measured using some images taken from different angles. And the relation between these values and the sensory evaluation was examined. As a result, the implications between them were found out. And, it was confirmed that this method can evaluate the sharpness of scalers objectively.

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Many remote monitoring systems are proposed from machine tools vendors and robot vendors. However, these remote monitoring systems are usually dependent on individual machine tool vendors or robot vendors.
On the other hand, conventional monitoring methods are indicating of camera images and control information to personal computers. However, there are monitoring limitations of network cameras because of lighting problems and/or the installation limitations of the cameras.
Therefore, 3-D remote monitoring system (3-D LIVE or 3-D Layered Information Viewing Environment) for multi-vendor manufacturing systems was developed. The 3-D LIVE uses ORiN (Open-Robot Interface for the Network), which is a de facto standard for accessing the robot system information for gathering information data at the multi-vendor device level consisting of robot controllers and machine tool's NCs. The 3-D LIVE manages information from the whole manufacturing line level to the device level of manufacturing systems by using linked multi-media data consisting of 3-D modeling, network camera's pictures and character's data. Then the 3-D LIVE can provide a visual monitoring environment, which is easy to understand for remote operators.
In this paper describes a configuration of the 3-D LIVE. A development of a prototype and results of test operation of the system are discussed.

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Distributed control systems (DCS) consist of many distributed sensors and actuators and a network interconnecting them, and are being introduced in various automation areas. For assuring the control performance of DCS under the heavy communication traffic, the simulation of DCS is strongly needed. For this purpose, we propose a uniform, efficient and systematic method based on object-oriented design patterns for modeling and simulating DCSs. In this paper, two design patterns are newly proposed. Statechart pattern describes classes and interaction for uniformly executing the state transitions in a finite state machine (FSM). Event-Chain pattern describes classes and interaction for uniformly dispatching the events among FSMs. The systematic procedures of implementation from the patterns to the Java code of the DCS model, are also discussed. Finally, effectiveness of proposed method was proved by developing a Java-based DCS simulator for distributed HVAC system.

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This paper focuses on shortening of drill-movement time in X-Y plane. TSP (Travelling Salesman Problem) has been applied to determine a moving route of PWB (Printed Wiring Board) holes arrangement. That is, some papers dealt with the improvement of the calculating time and accuracy of the TSP method to obtain the shortest route in geometrical problem. However, Considering both the characteristic of PWB hole arrangement and the feed control characteristic of machine tools, the shortest route of geometrical problem by TSP is not always in agreement with one of moving time problem. Therefore, we propose a CAM system of PWB drilling considering the feed control characteristic of machine tools using new TSP method to obtain the shortest moving time.

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In this research, an in-process machine for measuring the cross-sectional profile of parts that have textures on the surface, such as etched parts, is developed. A stripe pattern is projected perpendicularly downward onto the etched surface using an objective lens, and a reflected image signal h(x) is detected by a CCD camera. The cross-sectional profile is measured by moving the objective lens up and down. At this point, the reflected image signal g(x) is obtained by a CCD camera installed in the other detection system that does not project the stripe pattern. The technology for obtaining the stripe pattern signal f(x), calculated as h(x)/g(x), that reduces the effect of the texture on the surface of parts, is developed. Furthermore, a machine that has two optical systems in one unit is developed. h(x) and g(x) are detected at the same position on the surface of parts by separating the detected image into two images using polarized illumination and detection. The cross-sectional profile of parts with roughness Ra of 0.58μm can be measured within an error of ±1.0μm when the height of the surface of parts is measured using the image signal f(x).

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To establish a delta operator technique in fixed-point arithmetic, the previous report proposed a modified delta operator and form named Variable Modulation Method (VMM). The principle is based on the methodology of PWM. In the present paper, it is aimed to apply VMM to a PID controlling system and verify the availability of VMM experimentally. First, the problem of the conventional shift and delta operation in fixed-point arithmetic is described. Next, the outline of VMM for solving this problem is described. Furthermore, the implementation procedure of a PID control algorithm based on the shift and VMM form is shown, respectively. Finally, both methods are compared experimentally on the position control of the DC motor. In case of a 16 bit word-length, responses in using both forms are not drastically different from those in using floating-point arithmetic. In case of an 8 bit word-length, step and ramp responses in using the VMM form are almost similar to those in using floating-point arithmetic. Thus, the availability of VMM was made clear in case of a short word-length.

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Ball screw driving systems are widely used in the industrial machines such as machine tools. In such systems, a mass of load is an important factor not only for determining control gains, but also for designing an observer. However, the estimation of mass is often deteriorated due to the non-linearity of friction and disturbances.
In this study, a method to estimate a mass of load by using simple P-D control against friction and disturbances is proposed. Furthermore, the guideline for designing the P-D control gains with an unknown mass is shown. Finally, the effectiveness of the proposed method is shown experimentally.

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[in Japanese]

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[in Japanese]

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