In this paper, a polishing robot with a hybrid motion/force controller is proposed for polishing of PET bottle molds. A ball end abrasive tool is attached to the tip of the robot arm via a force sensor. The polishing robot has two main features. One is that the surface of the mold is polished by the polishing force acting between the mold and the abrasive tool. The polishing force is assumed to be considered as a composite force of the contact and kinetic friction forces, in which the friction consists of Coulomb and viscous frictions. The polishing force is controlled by a feedback loop action. When a PET bottle mold with curved surface is polished by the proposed robot, not only the orientation of the abrasive tool is fixed but also its revolution is locked. The other is that no complicated teaching task is needed. The motion of the abrasive tool is feedforwardly controlled based on a prepared initial trajectory, i.e., cutter location data. The velocities of the tool in normal and tangential directions are delicately regulated so that the polishing force can track a desired value. The effectiveness of the proposed system is proved by experiments using two industrial robots with an open architectural controller.

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Today nearly all die and mold makers use High Speed Cutting or Machining in cavity and core manufacturing. However, finishing processes for injection molding molds and die casting dies are done by EDM because these applications have many thin and deep cavities to be machined. Otherwise, the long solid carbide milling cutters are necessary for machining these molds and dies. To save set-up time and machining time, it is desire to machine by High Speed Cutting or Machining in such machining portions. To solve this problem, mold and die machining by indexing tilted tool axis on 5-axis machining center is proposed in this paper. In the proposed machining process, High Speed Machining is executed on each tilted tool axis. In this machining process, the list of indexing angle should be determined automatically, because the shape of the die and mold is very complex to determine the angle by an operator. Therefore, the main objective of this research is automatic determination method of the list of indexing angle for machining the die and mold. Firstly, we propose the calculation method of optimum indexing angle for required machining surfaces using normal vectors of the surfaces and cutting edge shapes similar to the Gaussian Sphere method. Secondary, we propose the machinable area evaluation method of calculated indexing angle based on inverse offset method with state flag. Finally, we illustrate an example to demonstrate the effectiveness of the proposed methods.

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Mesoporous silica materials with self-organized structures that consist of periodic nano-scale pores have been expected to be of great significance in realizing micro-nano systems. The morphological control of the mesostructured materials are demonstrated by varying the concentration ratios of CH₃(CH₂)₁₅N(CH₃)₃Cl (C16TMACl)/ (C₂H₅O)₄Si (TEOS) and HCl solution. The increase of the concentration ratios changes the shape and size of the mesostructured materials. Linear hexagonal rods, good example for this application, can be synthesized by the reaction of 7.04 g/4.48 ml for C16TMACl/ TEOS and 70 ml/20 ml for 5N HCl/H₂O. The most suitable calcination conditions for higher strength are determined by varying the calcination temperature up to 1000 °C. The hardness, elastic modulus and fracture load of the mesostructured hexagonal rods are clarified by nano-indentation method.

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In today's manufacturing industry cost competition is growing severer with the trend in production toward globalization. For high labor wage countries like Japan, low-cost and multifunctional automation technologies are required. This study focuses on the analysis of human dexterousness to develop new automation methods, because workers often find simpler work methods by task learning, and the methods can be clue to low-cost automation. In this study, the new “NAGARA System” in other words, “Station-less Assembly System” in which component parts are assembled directly by the base parts moving on the belt conveyor without positioning, is proposed. In this paper, firstly, the remarkable human characteristics of the manual system are extracted quantitatively. Next, based on the analysis, the new automation system, which introduces a force-changeable gripper and human assembly algorithms, is proposed. Finally, the effectiveness of this system is proven by comparing the productivity and the cost with them of the conventional one.

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Flocculants are used widely in sewage disposal plants and wastewater treatment facilities. Most operators would readily agree that there is need for evaluation of flocculation state in their plants. This paper describes a new method of quantitative evaluation of visual patterns in the aggregation of particles. Most studies on the pattern analysis have discussed the quantification of the shape. However, it is considered that patterns are characterized by the shape and aggregation degree of the particles. In this paper, SI(shape index) and AI(aggregation index) are proposed in order to quantify the shape and aggregation degree of the paricles. Many examples would be examined, and experiment for flocculants would be carried out as an application of this study. The results show that SI can quantitatively express the shape of the particle and AI express the degree of aggregation, and it is considered that it is advisable to use SI-AI distribution diagram to evaluate the particle pattern.

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In this paper, we describe the compensation sequence and the result of motion compensation of the newly developed versatile micro robot which can be applied to microscopic operation. In order to provide microscopic manipulation, the unique locomotion mechanism which is composed of four piezoelectric elements and two electromagnets is proposed. Here two legs arranged on cross each other are connected by four piezoelectric elements so that it can move in any directions, i.e. in X and Y directions as well as rotate at the specified point precisely with the manner of an inchworm. Moreover the combination of particular wave forms for piezoelectric elements can provide “arc trajectory with facing center”, that is important for the micro manipulator to keep its tip end within the microscopic view area. However, the versatile micro robot can not move precisely without the motion compensation because of the difference of characteristics of four piezoelectric elements and the assembling error of four piezoelectric elements and two electromagnets. We analyze the mechanical kinematics for locomotion and propose the competitive compensation method supported by the CCD camera based image tracking system. In the compensation experiments, we succeed in reducing the motion error and confirm the effectiveness of our compensation method. The design procedure, basic performance and biomedical application of this tiny robot also are discussed to open the new field for micro-robotics in precision region.

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A machine which can detect flaws deeper than 30μm and longer than 200μm on edges of vanes, produced by the barrel finishing process is developed. The edge part is illuminated with LEDs and Fresnel lens from the direction of ±60° and ±30°, which is measured from the vector normal to the edge, in a plane composed of an edge and a normal vector. The flaw on the edge is detected with a lens and a line CCD camera. This machine achieves the thoughtput of 8 pieces/s. A detectable angle of the flaw surface is analyzed theoretically and compared with experimental results. A method of classifying the detected images into two groups, the dust images and the flaw images, is also developed. All flaws can be automatically detected using the developed machine.

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Calibration of a parallel mechanism using a specified artifact is effective method. However, there are strong correlations between each parameter in an artifact calibration of a parallel mechanism. Therefore, it is difficult to identify all kinematic parameters included in a kinematic model of the parallel mechanism from measuring data. In this research, we propose to use a priori knowledge of the kinematic parameters and to improve mathematical condition of Jacobian matrix. Using the priori knowledge, all kinematic parameters of the parallel mechanism are identified in the artifact calibration with the least squares method. Firstly, the least squares method with the priori knowledge is formulated. Secondly, design values and tolerances of the kinematic parameters are used as the priori knowledge in the least squares method. Finally, the artifact calibration for the parallel mechanism with the priori knowledge is demonstrated. Using this method, all kinematic parameters are converged to adequate values. The simulation for this method directly implies that the kinematic calibration with a priori knowledge for artifact calibration of parallel mechanism in this research is useful to calibrate all kinematic parameters without divergence in the least squares method.

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Oleic acid coated on a surface of oxygen-free copper has been investigated for its effect on orthogonal dry cutting. Liquid paraffin as a non-polarity substance, liquid paraffin containing 0.02 to 2.0 mass% oleic acid as an organic polarity substance, and pure oleic acid were coated on the annealed and then pre-cut surface of the copper before the final cutting. The speed and depth of the final cutting were 1.67mm/s and 0.02mm, respectively. The following results were obtained : 1) The coating of liquid paraffin containing at least 0.02 mass% oleic acid was always effective to decrease the cutting force and to form thin flow-type chips with a fine serrated configuration on the free surface. 2) From the infrared spectrum measurement, the formation of chemisorption between oleic acid molecules and copper atoms was estimated at the upheaved region in front of the chip. 3) The chemisorbed molecules restrained the dislocation movement under the pre-cutting surface and affected the thin chip formation.

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Ultraprecision cutting tests were performed on single-crystal calcium fluoride. Effects of the tool rake angle, the cutting fluid type and the crystal orientation on brittle-ductile transition behaviors were experimentally investigated. It was found that two types of microfractures occurred in wet cutting; one occurred in high feed regions and the other appeared in very low feed regions. The boundary conditions for the occurrence of these microfractures were affected by the tool rake angle and the cutting fluid type. The microfractures occurring under the low feed conditions were due to the special thermal properties of the work material and could be avoided by dry cutting. In the dry cutting tests, the brittle-ductile transition boundary changed significantly with the crystal orientation. The minimum critical chip thickness for generating a uniformly smooth surface was 85nm.

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At the solder ball mounting process on the CSP(chip size package), must have inspection of solder ball residue on the vacuum nozzle(inhaling tool). This study is how to detect solder ball residue during vacuum nozzle moving when using photo sensor. First, the characteristic of photo sensor output value in the case in which all inhaling entrance contain the solder ball and case in which it is not so was clarified on one or several inhaling area. Next, when the inhaling area is several, in order to eliminate the effect of the light leak on the output value of photo sensor, the differential coupled method of photo sensor was proposed, and the effectiveness was confirmed. In addition, arrangements of photo sensor and mobile speed of the inhaling tool, etc. were examined, and the development of the practicable detection method was tried. With this result, we discover following. (1) The solder ball recognition on CSP can be detect by photo sensor. (2) We confirmed effectiveness of the differential coupled method of photo sensor. (3) Mobile speed of inhaling tool dose not influence the output value, when differential coupled method of photo sensor was used. It is indicated that this detection method is practicable for this fact.

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Cooling air jet turning needs to develop a supersonic nozzle that is capable of supplying high speed air jet at turning point. In this study, supersonic Convergent-Divergent nozzle (supersonic C-D nozzle), which can make stagnation-cold-air up to the sound speed in the convergent section and expand the cold air to supersonic speed in the divergent section, are designed on an assumption of thermal equilibrium under isentropic expansion (no change in entropy). Experimental evaluation of the supersonic air jet clarifies that the C-D nozzle is more advantageous than present convergent nozzle for the cooling air jet turning since the potential core of the C-D nozzle goes over 13 mm (max. 37 mm). As for cooling ability of the cold air jet in the potential core, average heat transfer coefficients of the cold air jet are 1,000-1,400W/(m²K) depending on both pressure of chamber p₀ and impinging jet air P. The optimum supply condition of each nozzle is verified experimentally and expressed using non-dimensional parameters, Reynolds number Re and Nusselt number Nu.

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In high speed turning of gray cast iron using a binder-less cBN tool, an intensive tool wear occurred in continuous machining operation over a period of 50s at the cutting speeds, V exceeding 40.00m/s. Since it was clarified that the intensive wear is caused by an abrupt temperature rise at the tool tip, a tool tip temperature controlling system to suppress the temperature rise and keep the tool tip temperature to a constant value during cutting operation was newly constructed. Applying the system, the tool tip temperature is controlled to an optimum region in which the tool exhibits a self-fixing function through formation of belag (aluminum oxide layer) on the tool flank face. As the results, the tool flank wear rate at cutting speed, V=45.00m/s reduced to as low as 1/50 of the case of machining at same speed without installing the temperature controlling system.

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Novel chemical mechanical polishing (CMP) process using a fixed abrasive tool (FX-tool), which is a kind of grindstone, was developed for dielectric planarization. In order to obtain flat surface for 45-nm-node of semiconductor generation, two points that are adopting stiff polishing pad/tool and reducing concentration of free-abrasives become critical issues. Newly developed FX-tool has more than ten times higher Young's modulus than that of a conventional CMP pad, and simultaneously, concentration of free abrasives on its surface can be controlled by polishing time. In experiments using several test-wafers, less than 30nm of dishing was obtained up to 3mm-length-pattern. Additionally, polyacrylic ammonium (PAA) effectively affects to increase degree of selectivity between oxide and nitride for shallow trench isolation (STI) process. The selectivity of 41 was obtained at 3 vol.% concentration of PAA. STI test wafers were successfully polished without any additional processes such as etching back.

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Precise periodic structures can be generated on the surface of various kinds of materials by linear polarized femtosecond laser of energies nearby ablation threshold. The direction of the periodic structures can be changed easily by polarization rotator. The technique was employed to create precise periodic structures of different directions with a ring pattern (radial type, concentric circles type, spiral type) on sintered tungsten carbide flats. This paper deals with effect of the periodic structures on tribological characteristics under sliding tests. Ring-on-disk tests and disk-on-disk tests revealed that the precise periodic structures take remarkable effects to reduce friction coefficient. Radial type and spiral type produced fluid film lubrication on wide sliding condition under ring-on-disk tests. Concentric circles type achieved low friction coefficient at low sliding velocity under ring-on-disk tests. Spiral type was the most suitable for reducing friction coefficient under disk-on-disk tests.

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Combination of optical lithography patterning in a thickly coated resist and electroplating into the resist replica is investigated for developing a new easy, low-cost and high-performance micro-fabrication method. In order to form patterns with a high aspect ratio and vertical side walls, low numerical aperture (NA) projection exposure is applied, and acrylic resist SU-8 with high transparency for the exposure light of near UV is used. When a lens with a low NA of 0.063 is applied, large DOF of more than 200 μm is obtained for 50-μm wide and 100-μm thick resist. If the focal position is adjusted suitably, 275-μm thick patterns with vertical side walls and a high aspect ratio of more than 10 are obtained. These resist patterns are printed on copper clad plastic boards instead of silicon wafers. The copper clad boards are directly available for electroplating without evaporating a base metal layers on them. Thus, fabrication of micro nickel gears is demonstrated successfully. Since the new method uses low cost optical lithography, it is applicable even for small production, and will be useful for fabricating various micro parts.

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Polycrystalline silicon (poly-Si) films were fabricated with high deposition rate using the atmospheric pressure plasma CVD (AP-PCVD) technique. The films were prepared on thermal oxidized Si(001) wafers at 500 °C in atmospheric pressure VHF (very high frequency) plasma of gas mixtures containing He, H₂ and SiH₄. Surface morphology, cross-sectional structure and crystallinity of the Si films were characterized by scanning electron microscopy (SEM), reflection high-energy electron diffraction (RHEED) and Raman scattering spectroscopy. Hydrogen content of the deposited films was also evaluated by Fourier transformation infrared (FTIR) absorption spectroscopy. It was found that the crystallinity was affected by the gas flow direction within the plasma area when the SiH₄ concentration was 0.1%. Amorphous Si (a-Si) grew at the upstream region, while poly-Si grew at the downstream region. It also became clear from FTIR spectra that hydrogen atoms that terminated the dangling bonds were excessively contained in the a-Si film. Those excessive bonded hydrogen atoms desorbed thermally during the film growth, and caused film peeling from the substrate. These results indicated that decomposition of SiH₄ molecules was not sufficiently enhanced at the upstream region due to lack of the input VHF power. By decreasing the SiH₄ concentration to 0.01%, however, poly-Si film could be deposited in the whole plasma area. It was found from SEM observation that columnar Si grain grew from the substrate surface, and the grain size increased as the film thickness increased. At the SiH₄ concentration of 0.01%, a poly-Si film was deposited in 100mm×100mm area by scanning substrate in twice at 0.3mm/s. The SEM observation revealed that the Si grain grew continuously at the interface between the first layer and the second layer, suggesting that crystallinity of the film was uniform in the whole plasma area. The deposition rates were 9nm/s for 0.1% SiH₄, and 4nm/s for 0.01% SiH₄, which values were more than 10 times faster than that by the conventional deposition techniques.

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This paper describes the relationship between the uniformity of wheel structure and the grinding performance in vitrified bonded cBN wheels. The variation in successive cutting-point spacing on the wheel working surface decreases by improving the uniformity of wheel structure. Therefore, it has been expected that an improvement of the uniformity in wheel structure enhances the grinding performance of wheels. However, the relationship between the uniformity in structure and the grinding performance is not yet examined sufficiently because it is difficult to manufacture the grinding wheel having such an uniform structure. In this study, we propose a novel method of manufacturing cBN grinding wheels that is possible to improve the uniformity in wheel structure. The uniformity in structure of the wheel produced by the novel method is improved as compared with that of the wheel produced by the conventional method. As compared with conventional wheels, wheels produced by the novel method provide lower grinding force, higher grinding ratio, better roughness of finished surface and longer tool life.

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