Environmental consciousness has been widely recognized as an indispensable requirement for product design. Requirements of the environmentally conscious product are more varied and complicated rather than those of a conventional product. In clarifying variety and complicated requirements, environmental consciousness has to be considered effectively in the early design stage. Systems that support environmentally conscious design, therefore, need to be based on models of clarification process of requirements by multiple designers over a product life cycle. The ReqC (Requirement-Centered) model for basic information structure and process of environmentally conscious design has been developed, which is based on observations and analysis of how designers make decisions about requirements during design meetings. This paper proposes the ReqC model, which consists of two submodels, i.e., the ReqDIS (Requirement-centered Design Information Structure) model for design information structure and the ReqCP (Requirement-Centered Process) model for convergent/divergent design process.

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In this equipment, the inner diameter of the specimen is measured by detecting an image of a small spot reflected at the wall of the specimen. In this report, the width of the gap between parallel plates is measured instead of measuring the diameter of the hole, and the factors that cause measurement errors are analyzed experimentally. The results obtained in the experiment are compared with the theoretical results discussed in the 1st report of this work. Since it is very difficult to make a specimen with a narrow gap, a special specimen with which the width measurement errors are evaluated without measuring the gap is developed in this work. The following results are obtained. (1) The measurement errors depend on the degree of defocus of the objective lens used for detection. (2) The inner diameters measured in the middle, or the inlet or outlet of the specimen are different. The difference is small when the gap is large and the numerical aperture of the lens is large. (3) The measurement errors are influenced significantly by the degree of defocus of the objective lens used for detection when its numerical aperture is large.

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This paper presents a precise XY-stage system specially designed for laser fine-cutting system. Analysis of dynamic behavior of the stage system, control system design and some experimental results are described. The stage system is guided on a base plate by linear motion bearings and driven by simultaneous operation of three linear motors in the x-, y- and θ_z-directions. The manuscript discusses the design of control system providing precise motion accuracy, using a force disturbance observer and decoupling compensation based on analysis of stage dynamics. Experimental results indicate that the proposed servo control method successfully reduces trajectory error for some motion command.

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This paper reports about a new actuator combining both a piezoelectric actuator and a voice-coil motor (VCM) for the applications of automatic assembly. A one degree-of-freedom of experimental setup is configured to examine the characteristics of the combined piezo-VCM actuator. The results of fundamental experiments are presented and an analytical model is described. The experimental results show that the proposed actuator can move a target object with step sizes in 10 nanometer-order by utilizing the impact force of a piezoelectric element while maintaining the comparatively long operation range of a VCM. It is shown that the hybrid actuator has attractive practical applications in the field of precision industry.

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A binocular machine vision system having an autonomously moving active viewpoint is proposed. Using this active viewpoint, the system corresponds feature points between right and left images easily and calculates the spatial coordinates of features. When the system detects an interesting region in the camera's image data, the system moves the viewpoint to the region autonomously, and measures the position of feature points in the region. The interesting region for the system is defined to be a group of points which cannot be corresponded and/or exist periphery of the camera's view field. The image caught by a camera is affected by optical aberration of the camera. For this reason, measured coordinate of a feature point which exists far from the viewpoint cannot be reliable. Therefore the system incorporates a weighting processes to reduce the influence of unreliable measurement by varying the weight according to the distance from the viewpoint of the system. An experiment shows the effect of autonomous movement of viewpoint and weighting process on measuring the spatial coordinate of an object.

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A method is proposed for stereoscopic depth measurement with stereo pair images of borehole wall. Increment sign correlation (ISC) is used to solve the stereo correspondence problem. ISC is a kind of cross correlation between binary-coded increment signs and has a binary or normal distribution, low computational cost, robustness against illillumination and occlusion. The method provides dense depth information and reliability of stereo correspondence by using statistical estimation of thresholds. Experiments with real pictures show effectiveness of the proposed approach.

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This paper uses HexaM made by Toyoda Machine Works Co. as an analytical model of parallel mechanism type machine tools. Much collision may be generated for its complicated structure and working space, when a workpiece is machined using this machine. For example, those collisions are generated between the moving components of the parallel mechanism, between the moving components and a workpiece and between the moving components aril the tool storage for automatic changing. In this paper, an algorithm for detecting and avoiding those collisions are proposed. The method for avoiding the collisions is conducted by readjusting the location of the workpiece without amending the tool path. It is confirmed through experimental works that the proposed algorithm is useful to detect the collisions prior to the actual machining.

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In coordinate metrology, a feature (Gaussian associated feature) is calculated from a measured data set of CMM (Coordinate Measuring Machine) using a least squares method. This data processing flow is called as "feature based metrology". In the feature based metrology, it is a key technique to estimate the uncertainty of measurement in the specific measuring strategy. The estimation method for uncertainties of measured parameters has been already proposed when the only random errors are put in the consideration. In this paper, the effects of systematic errors are theoretically analyzed to estimate the uncertainties in feature based metrology. The center position error and the diameter error of the ball probe are occurred from the random errors of probing in calibration process. These errors propagate as unknown systematic errors to the uncertainties of measured parameters such as the center position and the diameter of a measured circle. The method to calculate the error matrix was derived when the center position and the diameter of the circle are measured. Using this method, the uncertainties of the measured parameters can also be calculated in the complex measuring strategy. The series of simulations for this method in statistical way directly implies that the concept and the basic data processing method in this paper are useful to the feature based metrology.

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In this paper, a new kind of rotary encoder based on magneto-optical storage method is proposed. By using this method, a rotary encoder with small size, high accuracy and high response can be realized. MO encoder is more advantageous than a magnetic scale and optical encoder according to its high response and its high accuracy, respectively. High accuracy can be achieved by rerecording, therefore the error is corrected. Following issues are described: (1) A device for record, playback and evaluation of accuracy of MO encoder has been developed. (2) A necessary condition for record and playback for MO encoder was experimentally derived. (3) The MO encoder made for trial purposes was recorded by 2250 pulses per revolution directly from the referential encoder, as a result, accuracy of 2.5" and reproducibility of 0.079" were achieved.

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Squeeze air bearings are based on a phenomenon known as the squeeze effect, which causes a pressured air film with relative perpendicular motion between two planes. Unlike hydrostatic air bearing, it can be operated without air supply. The experimental device consists of the rotating shaft, piezo-driven four oscillating pads and displacement sensor to detect the motion error in radial direction. The pad displacement patterns consist of two functional motions; sinusoidal squeeze motion for the stimulation of air film and position control motion for motion error correction. Therefore applying a controllable displacement patterns, the detected motion error in radial direction can be corrected. It was confirmed experimentally that the shaft with rotating speed of 1 rpm was supported by squeeze air film. The motion error in radial direction was reduced with increasing amplitude of pad oscillation. The step response of no rotating shaft with PI controller was tested and the settling time less than 40ms was performed for step width of 0.5μm with appropriate proportional and integral gains. Finally, motion error correction was carried out for the rotating shaft at 1 rpm. The motion error before the correction with 2.5μm was to be undetectable.

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This paper deals with the influence of sulfonates having three kinds of different metal types on flank wear (tool life) and finished surface roughness in hobbing. Experiments were carried out using a fly tool. A sodium sulfonate decreases the flank wear of uncoated tool at a cutting speed of 117m/min, and a calcium sulfonate and a magnesium sulfonate are suitable for obtaining longer tool life with using a TiN and an (AI, Ti)N coated tool at cutting speeds of 117m/min and 159m/min, which are superior to the chlorinated fatty acid ester. The sulfonates used in the test improve the surface finish, which is smaller than that obtained with the chlorinated fatty acid ester. The use of sulfonates is effective for environmental pollution control and for improving the safety of the operator.

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The surface modification technology by electrical discharge machining with Ti powder green compact electrode has been applied to cutting tools, molds and dies. This method enables a high-speed surface modification which makes a hard layer of about several μ m thickness on workpiece. In this study, TiC semi-sintered electrode is developed for the surface modification instead of Ti green compact electrode. The electrode of semi-sintered TiC makes stable modification in large scale and the layer made with semi-sintered electrode has less defect. The effect of energy density in gap region on the modification process is discussed considering the hardness and the thickness of the layer, the electrode wear length and the piling efficiency.

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In this paper, the material removal mechanism in electrolytic grinding process is experimentally investigated by analyzing the stock removal due to electrolytic phenomenon and to grinding phenomenon in electrolytic grinding process, taking the inevitable accumulation phenomenon of interference depth of wheel into consideration. The material removal effect in electrolytic grinding is also discussed from the viewpoint of machining energy. Main conclusions obtained in this paper are as follows: (1) The electric current in electrolytic grinding process increases from beginning of wheel interference because of the momentary short circuit or electric discharge through generated chips at smaller concentration of electrolyte or applied voltage. Therefore all electric current isn't always consumed for the electrolytic effect. (2) There exists the critical electrolytic conditions from which the electrolytic effect in electrolytic grinding process intensifies. (3) The total consumed energy reduces with the increase of concentration of electrolyte or the applied voltage, but the effective energy rate for material removal decreases at about 7V in applied voltage.

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Linear motion error of the machine tool table consists of six components. So far, these components are measured separately, then the results of the measurement are different according to the method and the reference of the measurement. Therefore the new measuring method is proposed to measure all six components simultaneously and the new measuring system is made. This system consists of a laser interferometer system to measure positioning error, and three quadrant photo-diodes to measure two translational and three angular motion errors by detecting deviations of laser spot emitted from the laser source of the interferometer system. From the practical test on a milling machine with this system, the propriety of the proposed method is made clear.

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Numerically controlled plasma CVM machine has been developed in order to fabricate the ultra-high accuracy X-ray mirror efficiently without making the deformed layer. In this machine, gas bearing was applied to the rotary electrode for plasma generation and XY-table in order to maintain the cleanliness of the machining atmosphere. As a result of machining the plane mirror made of the silicon for the X-ray using this machine, 22.5nm (p-v) was achieved as flatness.

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Dressing of grinding wheel is a process for tuning the conditions of the wheel working periphery. Therefore, sounds emitted during dressing may be closely related to wheel conditions necessary to obtain particular characteristics of machined surfaces. If the conditions of the wheel working periphery change only a little with grinding time, the grinding states will be predicted based on dressing sounds. The purpose of this paper is to construct a system for predicting surface finish and grinding forces based on dressing sounds. First dressing sound is processed by linear prediction method to obtain its feature of power spectrum as a vector with auto-regressive coefficients. Then a neural network is used to relate a feature vector to surface finish or grinding forces. As result, it is verified that a developed system is applicable to the prediction of the grinding states.

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The study deals with the development of an integrated main processor of 6-axis control CAM system. The 6-axis control machining, where non-rotational cutting tools are used, has a lot of advantages, compared with the conventional one with rotational cutting tools. The main processors, which have developed till now, can generate CL data corresponding to the kind of 6-axis control machinings such as smooth machining, grooving, character line machining, sharp-edged corner machining, pocket machining, etc. However, it is not convenient to prepare the main processor for each 6-axis control machining method. To solve the problem, the integration of the main processors is intended, where CL data corresponding to specific machining method is automatically generated on the basis of judgment of the shape pattern standing for the kind of 6-axis control machinings. As a result, it was experimentally confirmed that the integrated main processor has the potential to select the suitable 6-axis control machining method and generate the corresponding CL data.

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Slicing with work rotating type multi-wire saw will be considered in the near future as one of the effective methods for slicing hard and brittle materials such as silicon ingots. In order to decrease the supplied value of slurry in slicing hard and brittle materials, the work rotating type multi-wire sawing characteristics using high viscosity slurry are investigated experimentally. This type of slurry is inferior to the conventional slurry in removing chips from the slicing regions due to its poor permeability. The work rotating type multi-wire saw is applied to improve the supply on slicing regions. Unlike the slicing process by a conventional multi-wire saw, the wire maintains intermittent contact with the workpiece during the process, thereby making it easy for slicing debris to escape from the slicing regions. Borosilicate glass, which is cylindrical (φ 10), is used as work material. The main results obtained are as follows. The work rotating type multi-wire saw makes it possible to use the slurry of high viscosity in slicing of hard and brittle materials. Using high viscosity slurry in work rotating type multiwire saw makes it possible to decrease the supplied volume of slurry. The use of high viscosity slurry in work rotating type multi-wire saw improves the surface roughness of the sliced surface.

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This paper deals with the contouring errors of circular interpolation motion in NC machine tools. In order to analyze the errors at the quadrant changes, a dynamical model of a feed drive is proposed including the nonlinear spring characteristics of rolling ball guide way and the coulomb friction of a ballscrew and its support bearings. The generation of exponential-type lost motion and stick motion, which appears at quadrant change, is analyzed and those amounts at each angle of the circular motion are calculated by using this model. Several motion tests are conducted on a test stand, and the measured contouring errors coincide with calculation representing the dynamic behavior of the lost motion and stick motion.

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Many reports on the cutting of hard and brittle materials such as single crystalline silicon and glass have been published so far, however, obtainable shapes have been limited because only turning tools or indenters have been used for cutting tools. From this point of view, in this study, an end mill-like microtool was adopted in order to machine by cutting three-dimensional microshapes with a high aspect ratio on these materials. The tool with a D-shaped cross section and a diameter of 20μm was fabricated using microelectrodischarge machining. With this tool, cutting of single crystalline silicon and glass was carried out at an axial depth of cut of 0.2μm. As a result, a slot of 25μm depth was successfully machined on silicon. Scanning electron microscope observation of the machined surface showed that the ductile-mode cutting was realized. A slot of 60μm depth was machined on glass, however, cutting was performed in the brittle mode. This indicates that, under the machining conditions for these experiments, the critical depth of cut of ductile-brittle transition in the cutting of silicon is larger than that in the cutting of glass.

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