During the conceptual design stage (the early and creative stage of the design process), computer aided support of designers' trial and error is very important. In this paper, the authors define and introduce the concept of behavioral prototyping, which is different from conventional dynamic simulation. The authors also discuss the design environment for behavioral prototyping. First, the requirements for the behavioral-prototyping support are presented. Next, a methodology of behavioral-prototyping support, to which the impulse-based simulation technique is applied, is proposed. The authors use the system for realizing the behavioral prototyping of a product. Finally, the authors evaluate this approach to behavioral-prototyping support by considering the data related to the designer's thinking process in the design.

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An identification number is carved by laser on a semiconductor bare chip for flip-chip-attach assembly. Each digit of an identification number is represented by the inclination of ID bars that are composed of five short lines. This paper proposes a method to recognize an identification number on a bare chip by image processing. The position and angle of orthogonal standard bars that are used to allocate ID bars are recognized by the combinational Hough transform using differences between edge directions of a pair of edge points. Inclinations of ID bars are measured using statistical distribution of edge directions. All identification numbers on 320 bare chips were recognized successfully, and the processing time recorded 0.37 second by an identification number.

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In succession to the 1st report which describes the theoretical background and outline of the "Totally Four-Dimensional Homogeneous Processing" method proposed by the author, comparisons are made, in this 2nd report, between the conventional Euclidean Processing method and the proposed one through many examples in terms of exactness, stability, simplicity, generality, uniformity and efficiency. Finally, a conclusion is given that we should shift the processing play-ground from three dimensional to four dimensional one.

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In our previous research it was proposed to evaluate a part upon its process planning difficulty perceived by engineer in process planning. In this paper the extended research is going to be described. It takes into account the differences in the perception of the difficulty in process planning among different manufacturing culture and environments in which engineer works. The research work started with an investigation delivered in a number of machine tool companies in different countries. The results of the investigation were then analyzed using various means, including a multiple regression analysis, to find out which influential factors are typical for a manufacturing culture and thus impact an engineer's consciousness about process planning difficulties. On this basis, an "engine" that would take into account the values arrived at in difficulty evaluation was developed. This engine could thus be used to predict the deviations of the difficulty evaluation in different manufacturing culture and environments.

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Considering machining efficiency, a cutter with large enough diameter should be used in rough machining of 2.5 dimensional pocket with islands. In this case, the most portion of unnecessary material is to be machined by the large cutter and the rest of uncut portion, by a smaller cutter. The first problem is to generate tool path for the large cutter so that the cutter can remove raw material as much as possible without interfering with the contour of the pocket and islands. The next problem is to detect the uncut areas that are left by the machining of the large cutter. In previous researches about pocket machining, only simple cases of uncut area have been considered. In this paper, an algorithm of tool path generation for rough machining process is presented and also a detection algorithm of uncut areas that are left in the rough machining is proposed. For pocket with islands, both composed with lines and arcs, the proposed algorithm can detect all possible kinds of uncut areas correctly.

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An actuator using shape memory alloy (SMA) has large power/weight ratio and is able to generate relatively large displacement. However there are only few examples of practical application in precision engineering because its dynamic characteristics are very poor. An SMA actuator deforms by being heated up and cooled down with deforming force. It is usually easy to heat up fast, but difficult to cool down quickly since the cooling time depends on the amount of heat flow from inside to outside of SMA. So dynamic response of the actuator mainly depends on the time to cool down. In order to improve the dynamic characteristics of the SMA actuator, the present paper proposes to put the actuator in water bath for cooling down actuator quickly. The effect of setting the SMA in water bath is experimentally examined. Responses of linear actuators of SMA wires set in air and/or water are compared with each other. For miniaturization, water jackets should be small. However if they are small, cooling ability becomes poor and temperature of water in the jacket rises up fast by repetitive drive. Therefore influences of size of the jackets, cycle time of repetitive drive and water temperature in the jacket are investigated.

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The present paper describes a new system to measure and control rolling of a precision stage. In this system, the rolling of the stage is monitored by a new measuring method, and is controlled to be zero by a feedback control system. The new method utilizes two angle probes to scan the rolling angle profile of the surface of a target mirror mounted on the stage. The principle of the method is based on the absolute straightness measurement by two angle probes and the technique to evaluate and correct the zero adjustment error between two probes. The output data of the two angle sensors consist of the rolling of stage and the rolling angle profile of target mirror. The rolling of stage and the rolling angle profile can then be separated from each other by using the angle sensor output data. Experimental results showed that the rolling can be measured and controlled to 0.05 s (arc) that is determined by the stability of the rolling measurement system.

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The present contribution deals with the automatic forming and the evaluation of its algorithm for information processing by using a nerve circuit network simulator. The new algorithm creates the initial nerve cell location based on information of a cellular composition matrix and can recompose the elements in this matrix. The automatic forming was implemented by applying the elite strategy algorithm so as to satisfy the three kinds of evaluation items: an isolation, a logic product and a logic summation of information. Also the ability of an automatic forming system was evaluated by introducing a "difficulty rate" of these three items. The proposed automatic forming system was finally tested with the computer simulation.

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The piezoelectric element has high positioning resolution although it suffers from the problem of a rather small displacement range. The proposed actuator can achieve both a high positioning resolution and a long stroke. This mechanism is modified the construction of Impact Drive Mechanism (IDM), and is named Smooth Impact Drive Mechanism (SIDM) because of the smooth movement. SIDM is com-posed of 3 parts, which are moving body placed on the base with little friction, piezoelectric element and friction part placed on the base with a certain friction. SIDM has coarse and precise driving modes. In coarse driving modes, saw-tooth voltage is applied to the piezoelectric element, and the movig body is moved in a long stroke with slip because of the inertia and the friction of the moving body. In precise driving modes, a slowly changed voltage is applied to the piezoelectric element, the main body is moved with the movement of the piezo itself without slip. An experimental translation stage incorporat-ing the SIDM has been built to evaluate the performance of the SIDM.

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Since our society is rapidly aging, equipment to assist daily living of the elderly becomes important. Rehabilitation robotics or mechatronics is one solution to realize such equipment. This paper describes a prototype development of an overhead robot arm to assist walking of elderly persons. For effective use in Japanese houses, the arm is mounted on a rail. Because of the rigid construction of this arm, the user can grasp the arm and recover his/her posture to prevent falling down. Force sensors are used both to provide an easy-to-use interface and to realize safety. The sensors can detect forces both horizontally and vertically. Thresholds of forces were determined to detect the user's intention to move as well as for safety considerations. Preliminary experiments resulted that the arm could follow the standing up, walking and sitting down of the subject. It was proved that the use of force sensors was effective to control the system.

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This paper describes a suppression of the thermal drift error and an extension of a measurement range to micrometers in the comparative length measurement using a regular crystalline lattice as a reference scale and a dual tunneling unit scanning microscope (DTU-STM) as a detector. A thermo-stabilized cell, in which the DTU-STM can be set, was developed to reduce the temperature fluctuation to less than 0.05K. In order to assess the thermo-stabilized cell, direct length comparison between the certified scanning electron microscope (SEM) standard grating with a average pitch of 240 nm and highly oriented pyrolytic graphite (HOPG) lattice spacing, which is 0.246nm, was performed using the DTU-STM, whose main body is made from Super-Invar. Images of the grating and the HOPG were simultaneously obtained in the range of 1 μm. To shorten the measurement time and thus reduce the thermal drift error, the lengths of 1μm for the two samples were measured along the fast scanning axis. A new ultra-low thermally drifted DTU-STM, whose body is fabricated from ultra-low linear expansion glass, was also developed to extend a measurement range to micrometers in the comparative length measurement. Long atomic image of HOPG crystal over a 5-μm-long region along the fast scanning axis was obtained using the new DTU-STM in the thermo-stabilized cell. The experimental results show the possibility of the comparative length measurement in micrometers range with sub-nanometer resolution using the HOPG crystal and the DTU-STMs.

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The temperature of workpiece irradiated with CO₂ laser is measured using a new type of infrared radiation pyrometer with an optical fiber. In the pyrometer, a chalcogenide optical fiber and a two-color detector which consists of InSb and InAs detector are used. The power intensity of the laser beam during the exposure time and the two dimensional picture of the intensity distribution of the laser beam are measured experimentally. The measuring system for the intensity distribution of laser beam consists of MCT cell and an optical fiber. The temperature distribution on the workpiece irradiated with laser is calculated numerically using FEM for unsteady state. The change of physical properties of materials is considered. Comparing the experimental results with the calculated ones, the absorptivity of the work material for CO₂ laser is obtained.

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The micro-indentation and micro-scratch device is newly developed for trial purposes aiming to evaluate the mechanical characteristic of the material surface layer by a precision machining or a micro-processing. The device enables us to precisely measure an indentation load-depth curve, and to determine the micro-hardness, the micro-scratch hardness and friction coefficient of a subsurface damaged layer and a thin film layer of 1μm or less with the same equipment. It is found that the depth profile of the micro-hardness characterizes the thickness of a stress hardening layer of a diamond cutting surface, and that the friction coefficient of a monocrystal silicon is different from a silicon oxide thin film.

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In order to estimate dynamic stiffness of a spindle on a machining center, a method based on the natural frequency of a single-degree-of-freedom vibration system attached to the spindle was developed. Concerning the radial direction, a straight bar was fixed at the spindle of the machine, and the bar was excited by an impulse hammer in radial direction, and the natural frequency of bending motion of the bar was measured. Then the stiffness of the fixed end of the bar was calculated by using the frequency. Concerning the axial direction, the spindle with an additional mass and without the mass were also excited by the impulse hammer in axial direction, and the natural frequencies of the axial vibration of the spindle were measured. Then the axial stiffness of the spindle was calculated by using the weight of the additional mass and the frequencies. The end milling tests were also carried out on the machines, and the surface roughness of the workpiece was compared to the stiffness of the machine.

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In this paper, three-dimensional holographic pattern projection using computer-generated hologram was studied. The computer-generated Fresnel hologram was calculated by Mori's data suppression algorithm The computer system for generating holograms was constructed and the hologram was fabricated the photo-mask pattern generator. Using the fabricated hologram and a He-Cd laser (325nm), the patterns were generated on the resist film in the three-dimensional space.

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This paper deals with the development of a new machining method for 3-demensional small parts such as micro-aspherical lens, die and mirror. Now, it is trying to machine the small parts utilizing a micro-grinding and polishing processes. A diamond quill for the conventional machining process has a small diameter (0.1-1.0mm), however manufacturing of the quill is very difficult and a tool life becomes short. A new method, which is one of field-assisted fine finishing methods, is developed to solve these problems. It is named an electrorheological fluid assisted machining (ERM). In this process, polishing slurry is mixture of fine abrasive (diamond, GC or WA) and electrorheological (ER) fluid. A strong electric field (0-4kV/mm) is applied between a very sharp tool like a needle (negative electrode) and a fixed electrode on the workpiece surface (positive electrode), and viscosity of the polishing slurry is increased. The abrasive particles gather around the tip of the tool, and are softly held. The tool tip will be performed as a very small wheel in grinding or polishing the small parts. In this experiment, it is clear that ER effect of the mixture of ER fluid and abrasive particles is maintained, and that the reduction in the ER effect is under 20%. Next, the necessary instrumentation and control system of the ERM have been designed and built. The machine has an NC controlled 3-axis slide table and an ultra-precision air spindle. Using this system, basic machining tests were carried out. The polishing rate was 21μm/15min. The developed ERM method demonstrated excellent polishing performance.

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This paper deals with the accuracy of on-line estimations of the thermal elongation over whole length of the spindle and the thermal displacement of the spindle. The telemetering system is adopted to measure the axial temperature distribution of the spindle. At the same time the elongation and the displacement are measured by capacitive type displacement sensor. Estimated elongation and displacement are compared respectively with measured values, and it is clarified that the estimated elongation and displacement coincide well with measured values: accuracy with error within +3.5--1.6μm for 100μm elongation and accuracy with error within +1.3--1.3μm for 13μm displacement.

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In EDM process, material removal is performed by repetitious generation of a micro crater produced by a single discharge, and the machining force acting on tool electrode and workpiece can be reduced by controlling electrical discharge energy. Therefore, EDM is particularly effective method in micro machining. However, in die-sinking EDM process, it becomes more difficult to make a fine complicated shape electrode when its size becomes smaller, and it takes a lot of time to form the electrode, which makes the process inefficient. On the other hand, in the case of wire EDM, the corner of machined hole becomes round, since the wire electrode has round section. Furthermore, in the case of thinner wire electrode, it is not easy to handle the wire. From the above points of view, a new micro EDM technique for machining various fine complicated shape holes with a simple shape electrode is proposed. In this method, a slender electrode with triangular section, which was made by extrusion with fine precision die, is efficiently used. Experimental analysis made it clear that fine hole could be machined efficiently with the electrode. Various fine complicated shape holes could be obtained easily by combining machined holes with a triangular section electrode. It was also made clear that smaller corner radius shape could be machined with the electrode, which was reformed on the machine using the reverse discharge method.

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