[in Japanese]

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Although functional design is crucial within a design process, difficulties in dealing with functions prevented traditional CAD technology based on geometric modeling from supporting functional design. This paper proposes a new methodology for modeling functions, called FBS (Function-Behavior-State) modeling. The FBS modeling represents a function as an association of the designer's intention and a behavior needed for realizing the function. This paper also describes a computer tool to support functional design based on the FBS modeling. This tool, called the FBS Modeler, supports a designer not only to verify design solutions with qualitative simulation but also to generate design solutions through decomposition of specified functions and embodiment of decomposed functions. Experimental design case studies demonstrate the importance and advantages of the FBS modeling.

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A method by use of a general-purpose computer algebra system is presented which derives two kinds of interpolating curves for computer aided design by controlling curvature-profiles described as linea/quadratic B-splines. Compact algorithm owing to symbolic manipulation and good initial/default values from the conventional curves make it easier to use these flexible curves with curvature-profiles almost free from unwanted undulation.

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In the previous report, the authors proposed a new type of angle sensor with three tracking STM tips, which offers a real-time measurement of pitch, roll and yaw with nano-radian resolution. The purpose of this paper is to describe an atom tracking to measure yaw. The fundamental experiment, in which one tip tracks an atom peak of graphite, shows that the tip searches the atom peak by tip rotation with the radius of less than 0.1 nm. Yaw is measured with nano-radian resolution by having the tip track the atom peak.

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This paper presents recognition methodology of motion from 2 dimensional images. The following two problems are discussed : (1) how to define features for the recognition. (2) how to realize pattern matching. For (1), authors classify features into two : temporal ones and sequential one. Distances are defined with respect to two features. For (2), dynamic programming is introduced because of robustness of phase deflection, expansion and contraction. Recognizing experiments on the finger language showed the effectivenss of the proposed algorithm.

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It was reported in the former paper that, when a fused quartz is scratched by an abrasive grain, a series of pit (5-30μm) array can be formed and a series of light pulse array corresponding to the pit array is found to emit. In this report, various solid samples were subjected to observe the pulses and to estimate the momentary temperatures. The temperature was found to have a relation to the thermal conductivity of the material. Silicate materials (SiO₂ : fused quartz, single crystal and Pyrex glass), which have low thermal conductivities, show rather high temperature, even emitting line spectra near 300nm suggesting desorption of O₂ molecules from SiO₂. Diamond show rather low temperature, about 1500°C inspite of having the highest hardness, it is because the thermal conductivity κ is 2000W/mK, 1500 times that of the fused quartz. Metals having brittle nature emit pulses, however, they show rather low temperatures reflecting their high κ.

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An intelligent gripper has been developed. The gripper can handle an object of unknown weight and unknown surface condition with the most suitable grasping force. Additionally, the gripper can adapt the grasping force to the most suitable value for the object even if the weight or the surface conditions of the object change. The gripper has two parallel fingers. Each finger is composed of a mechanical vibration system having two degrees of freedom. The system consists of a structural finger, a support spring, a grasping finger, an absorber spring and an oscillator. In the grasping finger, a harmonic force is always generated and absorbed by a dynamic vibration absorber consisting of the oscillator and the absorber spring, so that the grasping finger is kept in a stationary condition and the oscillator vibrates with a constant amplitude. The object is grasped between both grasping fingers. When the object is grasped with the most suitable grasping force, not only the object and both grasping fingers become stationary but also both oscillators become stationary because harmonic forces are transmitted to the object from each grasping finger and the two harmonic forces cancel each other out. In this gripper, the grasping force is adjusted to the most suitable value as the amplitudes of both oscillators are reduced to zero. This paper describes a fundamental principle of this intelligent gripper and the principle is confirmed by experiment.

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A technique to improve the tracking of initial and terminal position of trace particles for particle tracking velocimetry (PTV) is presented. In this system, three separate images of the trace particles at their initial and terminal positions, and along their pathlines are made using a color TV camera and three RGB lights, and are stored separately as R- and G- and B-images. Using the green image of the trace-particle pathlines, the pair of trace-particle images at the initial and terminal position is determined that overlaps the endpoints of each pathline image, and velocity vectors are calculated. This system was used to measure the movement of white artificial tracers painted on two counter-rotating tables. Despite the fact that the two groups of tracer to move in opposite directions on the measuring-field plane, correct velocity vectors of all trace particle images were obtained.

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The Cycloid Ball Reducer has been developed for robot actuator. A motion principle of the reducer has been analyzed, and optimal design method using theoretical strength has been shown. In this report, a calculation method of the reducer's theoretical efficiency is shown. Then, using this method, the design parameters are investigated to make an optimal shape of trochoidal groove. The Oldham's type output mechanism is developed, as like as Oldham's coupling. Also a motion principle and an efficiency of this output mechanism are shown. It is clear that type output mechanism has a small efficiency fluctuation caused by kinematic motion. But this value is smaller than that value caused by machining error. And then, the prototype reducer is tested, it is proved that these theoretical efficiency can be estimated using proposed calculation method.

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An optical skid that uses the wide range of the critical angle method has a smoothing effect on high spatial frequency components. In the present paper, the extent of smoothing is estimated on grooves and gratings by calculating the intensity distribution on a detection photodiode taking into account the spherical aberration of the objective lens. Computer simulation shows that the spherical aberration of the lens at the image plane where the photodiode has been placed is the main factor responsible for the smoothing effect, the smoothing effect increases as the aberration increases. It is also shown that the ray which has twice reflections on the surface profile is another cause of the smoothing effect. Furthermore, with respect to grooves, the characteristics of the smoothing effect are seen to be related to the width and depth of the grooves, they increase as the depth increases or the width decreases. Good agreement is observed between the simulation results and the experimental results.

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The several characteristics of TiNi thin films treated by the new method, direct Joule's heat crystallization treatment method, were compared with those treated by conventional heat treatment method in an electrical furnace. As the results, the followings were clarified for reversible TiNi thin films : (1) the crystal compositions of the TiNi thin films treated by the new method were same as those by the conventional method, (2) moreover, the TiNi thin films treated by the new method were deformed larger than those by the conventional method, and (3) the optimum heat treatment condition for producing larger deformable TiNi thin film is found as 600°C×1 minute. From these results, the new crystallization heat treatment method is very useful for TiNi thin film actuators.

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In the shear-mode grinding of brittle materials, the performance of grinding wheels is often described as the grinding force, which usually changes during the process. However, it was ascertained that a steady constant grinding force exists under shear-mode grinding of optical glass of BK7. The existence of this constant force results in the following characteristics : 1) no residual stock removal, 2) no necessity of dressing, 3) no cracks in the ground surface. This paper demonstrates experimentally that the constant force is a repeatable deterministic function of grinding conditions including materials and wheel's surface.

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The magnetic barrel finishing machine was developed by applying the magnetic field rotation of an AC motor, whose rotor was removed. The electric and magnetic characteristics were measured by a trial machine, and the relation between the current and flux density was investigated. Furthermore, the flux density of the cylindri-cal space was measured in various directions. Informations on a new cylindrical type magnetic barrel finishing machine was obtained from the results of the experiments, and used to manufacture the new machine. The proper combination of the magnetic media, water, compound and abrasives can only determined by experiments. The media mass state in the direction of height was investigated, and improvement of the container was proposed by the authors. Based on the results, cast products of such precious metals as gold, silver and platinum were finish-ed by using a machine. This machine has succeeded in finishing precious metal castings with complex shapes and comparatively large sizes.

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Finish roll forming by forced displacement can be conceived as a method of eliminating errors in conventional form rolling under constant loads. This method produces a high-precision tooth profile by low-speed form rolling when a high rigid screw or cam is used at the pressurized section. In this study, the high-speed rolling conditions necessary to allow the new method to be applied in practical situations is discussed. The following conclusion was obtained : The module, number of teeth, addendum modification coefficient, prescribed design precision, and material characteristics are necessary for gear design data.Using these data, the precision of a form-rolled gear can be predicted from the relationship between the applied forced displacement of the tool and the theoretically calculated plastic deformation of the tooth profile.This conclusion was verified experimentally. For example, form rolling improves the accuracy of gear of module 5 from JIS class 3 to JIS class 0 or 1 when the loading force of the tool is 4 to 5 kN and the circumferential speed is 7 m/min.

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This study has demonstrated the possibility of cutting four types of plasma sprayed ceramics on an Al₂O₃-TiO₂ system using sintered diamond tools. This experiment investigates the fundamental cutting mechanism, tool wear and machined surfaces. Presently, sprayed ceramics are difficult situation to finish by way of cutting. Because, these materials are formed with laminated small spray particles, and the structure is highly anisotropy, and include some small pores in the grain boundary. Cracks caused by the cutting are developed along grain boundary. These many small cracks or fractures on the machind surfaces are formed due to the cutting. The progress of cracks due to the cutting depend on the direction of the sprayed deposit structure. Even by use of the diamond tool, the frank wear is stronger for cutting of the sprayed ceramics, but the cutting edge was observed as having no occurrence of cracks. The main factor of tool wear is abrasive wear. The structure the machined surfaces classified into the four categories, which are plastic deformation, cutting, small cracks on the sprayed particle and cracks in the grain boundary.

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The time dependent distribution of abrasive grain size in a lapping process has been obtained from the simulation which was described in the last paper. It has also prescribed the decrease in the amount of effective working grains. This paper describes a new analytical procedure to estimate a rational amount of additional abrasives at each time of repeated supply from the simulatiOn result. It is based on the concept that the rational amount is what is necessary and sufficient to supplement the decrease mentioned above. It is shown that the analytically estimated rational amount decreases with time in the beginning of a lapping process, however it gradually reaches a constant value. This seems to be due to the decrease in effectively working grains with time. Finally a lapping test is performed supplying the estimated amount of abrasive grains. The result shows that the additional supply is sufficiently effective, there fore it suggests that this analytical procedure and its fundamental concept are reasonable.

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6-Axis control machining by use of non-rotational cutting tools offers a variety of machining possibilities in combination with the conventional machining by use of rotational cutting tools. The study deals with sculptured surface finishing as one of typical 6-axis control machining applications, where a non-rotational cutting tool is fed along sculptured surfaces to finish a workpiece with the cusp height as low as possible. The machining by use of ball end mills often requires the tool change to adapt their cutting edge radius to a surface curvature of workpieces to be machined, which leads to the deterioration of surface quality. To carry out the surface finishing without tool change, a new concept is proposed that a cutting edge radius of non-rotational cutting tool is virtually varied by changing the cross-sectional configuration of cutting edge through the rotation and inclination around the tool axis. The method is put into the main processor to generate CL data. From experimental results, the method is found to be valid in finishing sculptured surfaces with a kind of non-rotational tools to some extent.

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The Al₂O₃/TiC/SiC whisker tools are fabricated with a view to improve mechanical properties, such as bending strength, hardness and fracture toughness of Al₂O₃/TiC composites. But, it has been said that the wear of the SiC whisker content ceramic tool results from the reaction between Si in tools and Fe in work materials in the case of steel cutting. This paper presents the reaction between Si and Fe, and the cutting performance of the Al₂O₃/TiC/SiC whisker tool. Then the reaction between crushed Al₂O₃/TiC/SiC whisker tool and carbonyl iron powder is analyzed by DTA and EPMA. The result of the DTA analysis is that the exothermic peak appears at 1160°C as the diffusion of Si into Fe. And the results are obtained by the cutting test with wear resisting copper cast alloy, the wear of Al₂O₃/TiC/SiC whisker tool decreases with the increasing SiC whisker contents. On the other hand, it is found that in cutting of S45C and FCD500-7, the tool wear of Al₂O₃/TiC/SiC whisker tool increases with the increasing SiC whisker contents. And the wear mechanism of Al₂O₃/TiC/SiC whisker tool has been discussed.

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In this paper, the application of grinding to process ceramic micro parts has been discussed. A compact size NC grinding machine was developed using a spindle electrically driven up to 40000 rpm and stages move every 1 rim pitch. Electroplated grinding wheels of 1.5 and 10 mm in diameter are prepared with diamond abrasives of #120, #325 and #800. The specifications of a grinding wheel and the grinding conditions to minimize grinding force and surface roughness of workpieces have been examined. As a result. when the #800 grinding wheel of 5 mm in diameter has been used. 2 mm long micro poles of alumina, silicon nitride and zirconia. of which diameters are 60 μm. 150 μm and 25 μm respectively. and 2 mm long micro shoulder pole and quadrilateral pole of zirconia have been obtained.

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