This paper describes how to fit a model and 3D range points. The model consists of superquadrics. M-estimation is used for the function fitting problem. And genetic algorithm is used for the determination of the initial parameter values. Our algorithm proceed followed steps.
First, a distance of point from the each part of superquadrics is calculated and a point of attribute is determined. And all of the points are calculated as same. Next, M-estimators of each range point is calculated. And the estimation function is defined by the M-estimators. Third, the polytope method is used for optimization of the estimation function. And the optimization is iterated using initial parameter values given by genetic algorithm. The experiment was conducted by the object of simple structure.

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Entity concepts and related definitions and axioms in General Design Theory are analyzed, and the paradoxical phenomena about General Design Theory is explained. Then, by investigating entity concepts in Abstract Design Theory, a mathematical theory of design based on the philosophy of General Design Theory and a mathematical theory of information flow, it is shown that entity concepts in these design theories correspond to noun phrases in Montague Semantics, a formal semantics of natural language. This is an application of linguistics to design theory, and a new phase of correlation of design theory and theoretical computer science through Montague Semantics can be expected from these investigations.

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Evaluation of color shading defects on anti-reflection coating is described. Color shading defects are caused by disturbance of coating thickness. The defect is observed as slight color difference. The relation between thickness disturbance and color difference is shown by using a simulation method. MacAdam's ellipsoid is effective to judge the quality of anti-reflection coating to pass or fail. Variation of color difference with thickness and observation angle is evaluated. Designing method of coating thickness, in which color shading is maintained a low profile, is suggested.

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This paper proposes an estimation method of mechanical properties in microscopic area using tapping with a micro-cantilever. Resonance frequency and amplitude of the cantilever change depending on the mechanical properties of the material tapped. In this paper, oscillating cantilever and viscoelastic specimen were modeled by mass-spring system with damper and their transient behavior during tapping was simulated. In experiments, different materials were tapped with cantilevers of which length is 1.28mm and the original resonant frequency is 31.77kHz, and the shift of resonant frequency and amplitude in tapping were measured. The simulation results were fitted on experimental results and the equivalent properties were estimated by model parameters. The fitting results coincided qualitatively with the actual ones.

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In this paper, a flexible robotic assembly system with decentralized architecture is studied. The system is designed to achieve high flexibility including reconfigurability so that it can adapt to changes in its manufacturing environment. The system consists of autonomous agents, “holons”; each of assembly devices is controlled by its own holon, “execution holon” and each of assembly and hand-over operations is handled by a holon, “operation holon.” Operation holons are dynamically created and destroyed to execute assembly tasks. When an assembly task is launched in the system, the task is decomposed recursively into primitive operations, which are allocated to assembly devices in real time by inter-holon negotiation. The performance of this task allocation mechanism is validated in simulation. Experimental results on an actual assembly system are also presented.

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An articulated type 3D robot teaching machine has been developed. This teaching machine has 6 degrees of freedom. It can produce the 3D coordinate data and orientation data of robot end effector. On the robot teaching task, easy operation and dexterity of the teaching machine is necessary to the teaching operator. The articulated type machine satisfies these requests but the accuracy is less than that of the Cartesian type machine, so the precise calibration is necessary to the articulated machine. On the 1st Report a calibration process was proposed but disregarded factor of error was found out. In this 2nd Report, we analyze the new factor of the measuring error and we have discovered the effect of the flexible coupling used in the teaching machine is very important. The measuring error of the teaching machine decreases about 1.0 mm to 1.3mm when the coupling is exchanged.

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The Hartmann test for measuring mirror surface aberrations accumulates integration errors when calculating the aberration on the basis of gradient data. For this reason, highly precise integration is desired. Here, we present a grating projection method modified from the Hartmann test. It involves using ray tracing and fringe scanning methods, in which sampling points can be set at arbitrary intervals. The authors propose a highly precise integration method appropriate for the grating projection method. In this integration method, three nodes are used, and Simpson's rule and the Gauss quadrature can be described in a unified manner. Furthermore, the relationship between the integration error and the coefficient that determines the interval between nodes is shown. We provide the coefficient conditions for rendering the integration error smaller than that of Simpson's 3/8 rule; this is a typical integration method. In addition, the advantage of this method is demonstrated by simulation experiments. The proposed integration method can be applied to any general precise numerical integration problem.

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High speed flow finishing method has recently developed, which has an excellent performance for polishing an inner wall of stainless steel capillary. However, its method seems to be unable to finish the inner wall of stainless steel pipe. Present paper focuses on the finishing of the inner wall of stainless steel curved pipe with high speed flow finishing method. It is found that an elastic string-type mandrel inserted into the hole of curved pipe has great performance on finishing, in which a diameter of mandrel is slightly smaller than hole size of the pipe. Experiments indicate that surface roughness of the inner wall of curved pipe decreases with the number of slurry flow pass. It is found that surface roughness of the inner wall of a 90°curved pipe decreases with the number of slurry flow pass, however, it incresases inversely after 80 passes and peculiar roughness curve is generated. On the other hand, a 180°curved pipe indicates that there is different surface roughness curve compared with 90°curved pipe. SEM micrographs describe that the spacing of grain boundary on the inner wall surface of the pipe extends gradually with the number of slurry flow pass, and it may be related to the variation of surface roughness.

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Ultraprecision surface preparation techniques to make atomically flat Si surfaces are strongly demanded in the next-generation semiconductor technology age. However, effective technique dose not exist particularly for Si(001) surface smoothing. The only possible technique is a heating method in the ultra-high vacuum, however it dose not have industrial feasibility. In this work, a new EEM (Elastic Emission Machining) system having ultrahigh cleanliness has been developed for semiconductor surface preparation. In the EEM system, ultraclean techniques such as a refining system for mixture fluid and numerically controlled sample stages hydrostatically supported by ultrapure water are developed and equipped. Machined surfaces are observed by AFM (atomic force microscope). Obtained images show that topmost atoms on the premachined surfaces are preferentially removed in EEM, and that the processed surfaces have atomic-level flatness.

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This paper aims to clear experimentally the influence of a coated cemented carbide tool and fluids on the surface roughness in the ultra-precision cutting of stainless steel SUS316. The experiments are executed by face-turning SUS316 with the cutting tool set on the ultra-precision lathe. The cutting fluids used are kerosene and water-immiscible cutting fluid. First of all, the influence of cutting fluid on the surface roughness is investigated. Kerosene is generally used as the cutting fluid in ultra-precision cutting of aluminum alloy, copper and so on. The surface measurement results indicated that the surface is rougher than Rz=100nm(P-V) at the short cutting length of 100m with kerosene. In the case of water-immiscible cutting fluid, on the other hand, the surface roughness is smother than Rz=50nm(P-V). Furthermore, it is found that the commercial coated tool is more useful for the ultra-precision cutting of SUS316 in no use of special equipments. The surface roughness of SUS316 is kept smoother than Rz=100nm(P-V) until the cutting length of 1,000m.

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This paper deals with the influence of hardness of work materials on behavior of crater wear mainly, flank wear and surface roughness, with various high-speed steel (HSS) hob materials coated with (Al,Ti)N in dry hobbing. Experiments were carried out using a fly tool. The results helped clarify the following points : (1) With chromium molybdenum steel SCM415 which was changed HB131, HB144 and HB161 in hardness, the crater wear decreases with increasing in hardness of work material, with using the three kinds of HSS hob materials, in which a powdered metal HSS SKH10 is effective for the crater wear. (2) With SCM435 which was changed HB172, HB195 and HB214 in hardness, the crater wear is smallest when SCM435 having HB172 was cut, and it was biggest when SCM435 having HB195 was cut. (3) The SCM415 having HB161 and SCM435 having HB172 are suitable irrespective of the change in the hob materials, in terms of the crater wear, the flank wear and the surface finished in dry hobbing.

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This paper deals with Difficult-to-Cut Rating (DTCR) which is a coinage proposed by the authors. DTCR is a rating of difficulty in machining, and it can be calculated from the mechanical and thermal properties of a work material. DTCR has good relation to the inverse of machinability rating (MR). Difficult-to-cut material, such as Ni base alloy, Ti alloy or Hardened steel, has been widely used these days not only in the aerospace industry but also in the public welfare industry. The aerospace industry has a large quantity of the machining data about difficult-to-cut material, while the public welfare industry has limited data. An accurate grasp of its machinability is essential to machine the material successfully. To calculate DTCR, a radar chart composed from four properties, hardness, tensile strength, elongation and thermal character, of a work material is used. As for thermal character, conductivity, specific heat and density of the work material are used. These four properties have an effect on tool life, cutting forces, cutting temperature, surface finish and chip shape. The radar chart gives a feature of the work material, therefore, the rough strategy about machining can be estimated from the chart.

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A thermal stress field induced by non-uniform temperature often causes crack extension. Taking advantage of this phenomenon, some glassy materials can be cleaved without leaving any micro cracks on the cleaved surface. In the present paper, a possibility of the multi-point simultaneous thermal stress cleaving is discussed for brittle substrates which are heated or cooled by a plane source. Under appropriate heating or cooling, a positive mode I thermal stress intensity factor appears at crack tips. If surface cracks were previously generated on a substrate along a checkerboard-like mesh pattern, the substrate can be divided simultaneously by a single process using cracked face cooling or back face heating. The section accuracy by back face heating is better than that by the cracked face cooling because the tensile stress is induced more uniformly by the back face heating.

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Oil direct injection cuttings were conducted on an NC precision cutting apparatus in order to investigate the differences in lubrication between lubricant applying effect and oil-submerged cutting. Lubrication at the tool rake face were also determined. Reduction in the cutting forces by oil direct injection was smaller than the oil-submerged cutting in every cutting condition, however, larger than the lubricant applying effect cutting in some conditions. The differences appear to depend on pumping of the chip on the tool rake face and lubricant applying effect on the side surface of work material.

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The study deals with an accurate cutting error prediction of end milling in the finishing operation. As it was indicated that the consideration of cutting edge roundness improves the accuracy of cutting force simulation, a new estimation method of cutting force has been proposed for end milling with the straight flute tools, based on the calculation of the actual depth of cut. The influence of cutting edge roundness was not considered in the conventional cutting error prediction. Then, the study proposes an extended estimation method of cutting error for the helical flute end mill. It is necessary to calculate the actual depth of cut with an accurate description method of workpiece surface since the amount of cutting error on workpiece surface usually changes with the height of a cutting flute. As a change in workpiece surface in machining is correctly estimated by the calculation of the actual depth of cut, the estimation of cutting error is attained by referring to the form of machined workpiece surface, which is left behind after the end mill passed. A prototype of simulation system is developed, based on the proposed method. The effectiveness of the proposed estimation method is demonstrated by making cutting experiments with helical flute end mill under the cutting condition of finishing operation. The predicted cutting error shows a good qualitative agreement with the measured one, thus the more accurate prediction of cutting error is realized by the proposed method.

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The generating mechanism of the compressive residual stress controlled statistically is significantly complicated in practical blast process. In this paper, the residual stresses were compared in a dynamic collision process and a static indenting process using a single steel ball against a steel plate (0.5%C annealed), in order to optimize the blast process conditions in the simple indenting process.
The static indenting test was carried out using the indenting unit with low stiffness installed in NC milling machine. The tensile residual stress at the dimple center decreases with an increase in the indenting load. The tensile residual stress changes to compression when the indenting load exceeds about 20kN using a φ10mm steel ball.
The dynamic collision test was carried out using a nail strike machine which can shoot at a speed up to 56m/s. The residual stress at the dimple center changes from tension to compression at a shot speed higher than about 40 m/s. The piling-up on the dimple shoulder in the dynamic collision test is larger than that in the static indenting test, when the indenting force is loaded equivalent to the shot speed in the dynamic collision process. That is, the residual stress generated in the blast process can be evaluated using the results in the static indenting process, although the shot speed influences substantially on the dimple profile, but scarcely (<±5%) on the surface residual stress.

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The stagnation pressure, which is the sum of static and dynamic pressures, has a great influence on machining performance in laser cutting. Therefore, increasing the velocity of assist gas is effective in reducing the height of dross. In this paper, Laval nozzle was newly designed, because it can increase the velocity of assist gas flow spouted from nozzle tip. Effects of Laval nozzle on assist gas flow and the machining results in precision cutting of thin metal plate by a pulsed YAG laser were experimentally investigated. Assist gas flow from Laval nozzle does not have Mach Shock Disk and goes more straight than a traditional convergent nozzle. Therefore, the pressure on a workpiece increases, since assist gas flow from Laval nozzle can utilize energy more efficiently. However, caution is necessary in setting the cylinder gas pressure, since Laval nozzle has many unstable regions, where the pressure on the workpiece changes periodically. Using Laval nozzle makes it possible to reduce the height of dross even under low cylinder gas pressure condition compared to convergent nozzle. Thus the consumption of flow quantity of assist gas can be reduced, when the same height of dross is desired. Moreover, it was pointed out that the convexed inner wall of nozzle leads to the reduction of dross generation and unstable region.

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The high speed endmilling of Ti-6Al-4V alloy is investigated. Cutting temperature was measured by the tool-work thermocouple method, and the wear of the tool against the real cutting length was evaluated. The temperature increased in power law of cutting speed, feed, and radial depeth of cut as can be observed in turning. Wear rate of the tool was conastant below 550°C because the wear dominated by the abrassive wear. However, the rate increased linearly against the temperature in log-log plot beyond 550°C because the wear was influenced of the thermal wear. From the viewpoint of the cutting temperature, high speed endmilling of the alloy is recomended where the high accuracy, and the good surface finish is needed, while the low speed, high feed and large depth of cut is recommended when large chip removal rate is the top priority.

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