This paper presents an effective tool path generation method for machining of free-form surfaces of molds and dies with ball end mills. Parametric surfaces are generally adopted to represent free-form surfaces of products by progress of CAD systems. The proposed method is to generate the tool path immediately by referring to the parametric surface equation such as NURBS form. Therefore the tool path is generated easily even when the geometry of the cutting tool changes. It can also generate accurate cutter locations without any offset approximations. And furthermore the tool feed rate can be controlled properly at the cutting point on the product surface. The fundamental procedure of the proposed tool path generation method is described here and some cutting simulations are executed for the verification of the proposed method.

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A Ti(C, N) coated tool which has a balanced performance of the expected high wear resistance in the coated layer with high toughness of the substrate, has been widely used for machining of ferrous materials. Applying this tool to the machining of the nodular cast iron, however, formation of the adhered layer at the tool tip occurred intensively, tool-tip failure and or separation of the coated layer tends to take place especially in semi-final and/or rough finishing. It is also indicated that there is possibility to yield a finished product with some faults caused by continued cutting operation without noticing serious damage occurred on the tool-tip. In the present investigation, effects of reducing the pre-existing cracks in tool surface layer, thickness of the coated layer and the existence of the η phase in substrate material (WC-Co) on the tool life were extensively investigated in order to increase efficiency and to stabilize the tool life on the cutting process for semi-final finishing of nodular cast iron. As the results, it is clarified that the thinner the coated layer the lower became the tensile residual stress on the surface, resulting in the extension of the tool life without taking place separation of the coated layer. The separation is also able to suppress by controlling the surface roughness of the tool substrate to several μm with certain homogeneity.

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The purpose of this paper is to determine experimentally the fundamental data of the new artificial synovial fluid, which suppressed the use of sodium hyaluronate (HA). Consequently, a fundamental study is carried out using fibronectin (FN), which is the cell-adhesive proteins that exists in human blood and synovial fluid. The new artificial synovial fluid consisted of FN, dipalmitoyl phosphatidylcholine (DPPC), HA and isotonic sodium chloride solution (I.S.C.S.) as solvent. An evaluation of new artificial synovial fluid is employed by the friction tester with reciprocating slider. In order to verify from an engineering standpoint, the evaluated items are the total amount of wear between the cartilage on articular head of pig joints and the ultra high molecular weight polyethylene (UHMWPE) socket; and the amplitude of vibration which is analyzed with FFT at 80Hz, the resonant frequency of the movable portion in the friction tester. The results indicated that the artificial synovial fluid containing FN was effective in the reduction of the total amount of wear and the amplitude of vibration. Further, it turned out that the effect of vibrational reduction was better than the effect of wear reduction if FN is added to artificial synovial fluid. Therefore, the results at an engineering standpoint could confirm that the artificial synovial fluid containing FN had a good performance to the vibration-proof effect.

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The next generation of lithography with ArF eximer lasers will decrease the focus depth to ±0.5 μm. A chucking error of less than 0.03-0.05 μm in a 30-mm-square field must therefore be achieved, excluding the region 2 mm from a processed wafer edge. A new static-pressure seal-type vacuum pin chuck whose vacuum seal extends beyond the wafer edge has been developed. This paper describes the chuck structure, the pin characteristics, and the flattening ability around the wafer periphery, which was calculated by the finite element method. Experimental results for 4 and 8-inch wafers agree roughly with the calculations. The diameter of pins made of pore-free ceramics is smaller than that of those made of alumina ceramics. As the hardness of the pore-free ceramics is almost half, pin corners are not irregular. These features greatly reduce the influence of dust and scratching. The flattening ability with the static-pressure-seal-type chuck is two times better than that with the ring-seal-type chuck in spite of the low vacuum pressure of -78 kPa. The allowable process-induced concave bow for a 775-μm-thick standard 12-inch wafer is 600 μm when a chuck whose seal extends 1 mm inside from the wafer edge is used.

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In this paper, an improving process of surface roughness in cylindrical plunge grinding with a super-soft grade resinoid bond wheel, whose bonding material is prepared by the interaction of polyvinyl alcohol and thermosetting plastics, is discussed, analyzing the ground surface profile, the topography of acting wheel surface and so on. Main conclusions obtained in this paper are as follows: (1) Minimizing phenomenon of surface roughness in which surface roughness decreases down to the minimum after start of grinding is remarkably occurred in plunge grinding process with a super-soft grade resinoid bond wheel. And the phenomenon is useful for improving surface roughness by grinding. (2) Decrease of number of simultaneously acting cutting edge by a rapid increase of wheel wear leads to worsen the surface finish just after the point of minimizing surface roughness. (3) The number of simultaneously acting cutting edge is obtained by ground surface profile, topography of acting wheel surface and interference wheel arc length.

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In this paper, the structural configurations of 5-axis machining centers are researched, and a proposed method is applied to the measurement of the geometric deviations of the available machines, and the effectiveness of the method is discussed. The structural configurations of the 5-axis machining centers are divided into three types. The ball-bar technique is applied to the measurement of simultaneous 4-axis control motion, and the error motion is simulated using the motion analysis software. As the results, the geometric deviations in three types of 5-axis machining centers can be estimated by the proposed method. 5-axis control motion using a simplejig is proposed as alternative measurement method, and it is found that the proposed method is effective to evaluate the geometric deviations as well as 4-axis control motion.

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Recently distributed control systems (DCS), which consist of many devices and a network interconnecting them, are introduced in various automation systems. For assuring the control performance 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 DCS. Two design patterns are newly proposed. Device-Constructor and Composite-Device-Constructor patterns describe classes and mechanisms for uniformly structuring device models composed of sensor and actuator models, and for uniformly structuring composite device models composed of device models. The systematic procedures of implementation from the patterns to Java code of the DCS model are also discussed. Finally, effectiveness of proposed method was proved in developing a Java-based DCS modeler and simulator for building automation area.

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In this paper, a line-less production system is proposed to realize a system which can deal with complexity and uncertainty in changing production environments. The line-less production system can be defined as the system in which all production elements can move on the floor. To, realize the line-less production, the concept of Biological Manufacturing System is used, i.e., a potential field based self-organization is adopted. The effectiveness of the line-less production system is discussed, and the computer simulation is developed. The comparison results with a line-wise production system demonstrate the feasibility of the proposed line-less production system.

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Some eco-friendly machining methods, such as MQL machining and cold-air jet machining method, have been recently developed instead of the traditional wetting machining. The carbon dioxide emission in the traditional wet turning method and the eco-friendly turning methods were estimated using Life Cycle Assessment (LCA) method in order to clarify an effect of eco-friendly machining on the environment. Inventory data concerning the carbon dioxide emissions was estimated based on the experimental results and literature. The evaluated carbon dioxide emissions from both the machining methods of the wet and the eco-friendly were compared.
The amount of the carbon dioxide emission from the eco-friendly machining method marked 8.1×10 ³ kg/year for the cold-air jet and 8.7×10 ³kg/year for the MQL, less than about 70% of the amount of that from the wet machining method. Each annual cost was also estimated in the same conditions of the estimation of the emission. The annual cost of the production on the cold-air jet machining method marked approximately 70% of that of the wet. This study verifies that the eco-friendly machining methods are capable of producing smaller amount of the carbon dioxide emission than the wet machining method.

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A high accuracy and non-destructive absolute surface profile measuring system based on wavelength scanning interferometer has been developed. This system combined a compact interferometer based on Michelson interferometer with an electronically tuned Ti:sapphire laser for wide range wavelength scanning. This system measures absolute profile of object up to measurement height range of 1.5 mm for area of 2.5 mm × 5 mm. The depth resolution by quantization is approximately 3 μm. For improvement of the system, signal processing methods such as laser intensity revision method, phase revision method and interpolation method are adapted. From laser intensity revision and phase revision by Hanning window, S/N ratio of peak spectrum detection improved from 12.0 to 25.4. Five types of interpolation methods are tested to improve depth resolution. Using variable width cos ²θ fitting method, the depth resolution improved up to 0.06 μm. Experiment of profile measurement of Japanese one yen coin is done, and the accuracy of measurement is approximately 2 μm. The experimental results show the signal processing methods are useful for the profile measuring system.

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Brain wave is a representative sensory signal of a human body and shows different frequencies depending on the emotion. In this paper, a robot manipulator operated by the brain wave is discussed and its motion is evaluated by the subjects through questionnaires. When we face a comfortable scene or feel relaxation, our brain wave generally presents an α-wave signal with the frequency band of approximately 8 to 1 3 Hz. In this case, the α wave particularly shows a 1/f fluctuation, i.e., the corresponding power is inversely proportional to the frequency. This fluctuation is said to be comfortable for human. With this background into consideration, the 1/f α-wave signal obtained under a comfortable music was input to the robot manipulator by controlling its angle. To evaluate this motion, questionnaires were implemented for twenty subjects by watching three kinds of orbits of the manipulator motion: a 1/f motion, a 1/f ² motion, and a white noise-like motion. It was suggested from the test that 90% of subjects felt comfortable in the 1/f manipulator motion.

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Recently, the coordinate measuring machines (CMM) are widely used for a large measuring field. In general, CMM indicates Cartesian type of CMM (C-CMM). But another type of CMM exists, which is called an articulated coordinate measuring machine (A-CMM). The A-CMM is more flexible and useful than C-MM, because it has more degrees of freedom than C-CMM. However, it is difficult to keep the traceablity of it because the calibration of A-CMM is performed by the manufacturer's own method. Then, we propose the Estimation Method of Uncertainty of A-CMM. At first, kinematical parameter of A-CMM is described in D-H notation and kinematical parameters are estimated. Secondly, the kinematical parameters are calibrated using an artifact. We used 3D ball plate. We measure the artifact in five different locations and orientations. 45 points are measured and the parameters are determined in each location and orientation. The parameter assessment was performed. The result is better than the original accuracy. The uncertainty budget of balancer of A-CMM and exchanging the stylus are investigated.

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Recently, an electroless plating process is widely used for electronic industry. But, the plating film is often detached from the substrate owing to the internal stress. The origin of the stress in films is not certain. In order to determine the origin of stress in films, measurements of film stress are required in the earliest stages of film growth. This paper shows the possibility of applying TV holographic interferometry to such experiments. The macrostress can be obtained by measuring the bending produced in a thin substrate by the action of the film. In this study, TV holography, which can capture holographic image at TV frame rates, is used to measure sensitively the deflection of the free end of the cantilever beam. Continuous in-situ measurement of the film stress during plating was readily accomplished with this technique. The relation between film thickness and the internal stress for a Cu plating on a Be-Cu substrate was discussed.

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Calibration methods for 3D mechanisms are necessary to use the mechanisms as coordinate measuring machines. The calibration method of coordinate measuring machine using artifacts, artifact calibration method, is proposed in taking account of traceability of the mechanism. There are kinematic parameters and form-deviation parameters in geometric parameters for describing the forward kinematic of the mechanism. In this article, the kinematic parameters which describe the forward kinematics when all elements of the mechanism have no form deviation, are taken up to be calibrated using artifact calibration method. Firstly, the calculation system which takes out the values of kinematic parameters using least squares method is formulated. Secondly, the estimation value of uncertainty of measuring machine is calculated using error propagation method. The artifact calibration method is applicable to various types of 3D mechanisms.

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A figure measurement system with a stitching method has been developed for evaluation and fabrication of the ultraprecise hard X-ray mirror optics. This system was constructed by two interferometers. One is the Michelson-type microscopic interferometer which is improved to keep the focus distance within 0.1μm. Another is the Fizeau's interferometer employed to compensate stitching error in the long spatial wavelength range. To estimate the absolute accuracy in this figure measurement system, the reflection X-ray intensity distributions of flat and asphericl mirrors, which are fabricated by us, were predicted by wave-optical simulation based on measured profile and compared with actually observed distributions. As the result, they are in good agreements. These agreements prove that the developed system has sub-nanometer absolute accuracy in all the spatial wavelength range longer than 0.5mm, because sub-nanometer figure error in those spatial wavelength ranges are known to affect reflection X-ray intensity distributions.

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Low-temperature growth of epitaxial Si films at high rates by atmospheric pressure plasma chemical vapor deposition has been investigated. Si films are deposited on (001) Si wafers in gas mixtures containing He (98.9%), H ₂ (1%) and SiH ₄ (0.1%) at the substrate temperatures from 530 to 690°C. The films are characterized by reflection high-energy electron diffraction, atomic force microscopy and cross sectional transmission electron microscopy. High quality Si films with excellent crystallinity and surface flatness similar to or better than those of the commercial CZ-Si wafers are grown in the area where the deposition gap between the substrate and rotary electrode is small. Especially, in the epitaxial Si film grown at 610°C with 2000W, no lattice defects are observed by transmission electron microscopy. The maximum growth rate is about 6.6μm/min at 690°C and 1.2μm min at 610°C, which is about 20 and 4 times faster than that by the thermal CVD at 1100°C, respectively.

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