This paper describes the development of a cellular machine which aims at solving problems of the present mechatronics technology. The cellular machine consists of homogeneous, modular and autonomous cells. Each cell autonomously behaves based on local information accumulated through local communication. The cellular machine has several advantages. First, it is fault-tolerant, because it is highly redundant and it can maintain its functions by logically reconfiguring itself even when some cells are faulty. Second, it can also be physically reconfigured by adding or removing some cells. Thus, it adapts to changes of the user requirements and the environment. Third, designing software for each configuration is not necessary, because no central software is needed to control the entire system. We designed and built a "Cellular Automatic Warehouse" as an example, which demonstrated the advantages of the cellular machine.

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The photothermal deflection of a microcantilever is much increased with a bimorph and an antireflection structure. The deflection is more than half wavelength by the temperature rise of 100°C which is expected by an optical absorption of over 98% for the antireflection coating of Au/Si₃N₄/Au fabricated on the bimorph structure. The designed cantilever monolithically integrated on gallium arsenide (GaAs, λ=0.83 μm) or indium phosphide (InP, λ=1.3μm) will be used for the external-cavity length change of a tunable laser diode.

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This paper describes the generation mechanism of sound caused by mechanical actions of abrasives under lapping process. It has been shown that the surface roughness of the work can be monitored in process by detecting the power level of the vibration signals, in the frequency range of 1-3kHz. To establish the monitoring technique, it is necessary.to make clear the generation mechanism of vibration signals in lapping process. We assume a mass-spring system that consists of the work and the abrasive grains as a simple model for analyzing the vibration of the work. The elastic deformations of the contact portion between work and abrasive grains are regarded as springs and the work is regarded as mass so the Hertz's contact theory can be applied. The number and the representative diameter of abrasive grains that take part in the process were estimated from the enumeration data. In the vibration test, the resonance frequency of the system obtained theoretically were fairly coincident with the experimental results under wide range of abrasive diameter and lapping pressure. It was also confirmed through the experiments of model lapping that the generated sounds were distributed in the frequency region lower than the resonance frequency, and the distributions were in correspondence with the abrasive diameter and surface roughness.

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This paper clarifies the reasons for the minute tool electrode wear in the dry EDM. In the dry EDM, which has been newly developed, a high velocity gas flow supplied through a thin-walled pipe electrode removes and flushes the molten workpiece material out of the working gap without allowing it to reattach to the electrode surfaces. The greatest advantage of this technique is that the tool electrode wear is almost negligible for any pulse duration. It is thought that the attached molten workpiece material protects the tool electrode surface against wear. That is, the molten workpiece that has a higher melting point than that of the tool electrode adheres to the surface of the tool electrode that has a higher thermal conductivity than the workpiece. To verify this idea, the influence of the layer thickness of the workpiece material precipitated on the tool electrode surface on the temperature distribution in the tool electrode was numerically analyzed Then the tool electrode wear was simulated based on the result of the above heat conduction analysis. From observation of the cross section of the tool electrode surface, it was found that the tool electrode wore by the depth of only 2 μm during the early stage of successive pulse discharges since the initial surface of the tool electrode was not covered with the steel layer. As the thickness of the steel layer increases, however, the wear of the base metal of the tool electrode ceases in one minute and thereafter the layer thickness is kept constant at 8.5 μm. These experimental results coincide well with the simulation results.

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Ceramic powder is added into an electron beam melted pool and mixed with substrate material. The injection requires the powder to stay in the resolidified surface layer without being completely decomposed. Several kinds of ceramic are tried into steel substrate, and TiN and TiC are successfully injected. Three powder supplying methods are studied for TiN injection into steel. They are: (1) feeding by mechanical vibration, (2) preplacing on the substrate fixed with water glass, and (3) preplacing on the substrate covered with thin plate of material similar to the substrate. The evaluation is based on the measured portion of TiN particle in unit area. The third method shows the most injected TiN particle portion. The reason is considered to be effective suppression of scattering of the powder by the cover plate. Water glass fixing of powder does not suppress the scattering sufficiently. Mechanical vibration feeding is too weak to force powder into the melt pool. The uniformity of distribution of injected TiN is low. However the uniformity becomes higher as injected volume of TiN increases.

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The slider mechanism of wheel head by intermittent holding of vertical guideway is proposed and studied. The experimental apparatus is made for the model of the vertical guideway. The grinding wheel head slider is fixed to the vertical guideway during grinding by the elongation of PZT actuator and is released during feed motion in the direction of depth of cut. Metalic slide material is tried to be used for the guideway surfaces without lubricating oil. The characteristics of the static rigidity and the repeated motion of holding and releasing are examined experimentally and considered. Further, method to check guideway space and device to keep constant pressing force are proposed. The results are as follows: (1) Increase of pressing force (holding force) causes increase of static stiffness. The siffness is able to be estimated with the relations between contraction and pressed force of guideway surface. It is estimated that the static stiffness of the apparatus on pressing force P=150 N (Stress=0.3MPa) is more than 6 times of the static stiffness of usual guideway. (2) Good response of repeated motion is obtained. Slider keeps the same position during grinding operation and also the depth of cut 0.05 μm is easily fed.

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This paper presents a multi-axis control method using a model matching method for feed-drive systems of CNC machine tools. The servo system of each axis of a machine tool is independently tuned up. We try to tune up a machine tool matching Y-axis to X-axis. In machine tools the X-axis is usually mounted on the Y-axis, and the Y-axis has larger mass and lower natural frequency than the X-axis. Therefore, the Y-axis yields resonance or overshoot. In circular motion using P control, when proportional gains of X and Y axes are different, the circular trajectories generally become an ellipse. In order to solve these problems and to improve the accuracy of machine tools, this study proposes a multi-axis control method applied a feedforward compensator to a feedback compensator based on P control and a feedforward compensator designed using the model macthing method. Experimental results show that proposed feed-drive systems have good performance in cornering and circular motions.

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The plastic deformation method has been investigated for mounting an optical rod lens which is used to introduce the light from the semiconductor laser into the optical fiber. In this method the cylindrical rod lens of 2mm in diameter and 2.1mm in length was fixed by using the plastic deformation of a metal pipe. First the stress in the fixing process was evaluated experimentally and numerically. It is found that the gap between the lens and the pipe had to be small enough and that the. pipe had to be pressed with the optimal load in order to fix the lens without any breakage. The tension stress of 3MPa is loaded on the lens surface. This value is much smaller than that of the breakage stress of the lens. Next the airtight fixing was evaluated experimentally. It is found that the airtight fixing is accomplished by thickening the metal film on the lens and annealing the pipe. The fixing strength was kept after the heat cycle test. From these results this method is found to be quite effective for mounting the optical lens in optical communication modules.

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To realize highly efficient high speed milling of curved surfaces, it is important to resolve problems such as the generation of NC data, and the design of machine tools which will keep up with the new requirements. The reciprocating layer cutting path method serves as one solution to these problems. The aim of this study was to prototype a novel high speed milling machine. With an air bearing spindle, rotational speed of more than 100000 min^-1 are realized. By providing a U axis against the X axis, feed speed of 100 m/min and acceleration speed of 2 G is possible. Milling experiments are carried out to clarify the advantages of the method

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Machined surface properties of plain-woven C/C composites have been investigated. SEM observation results indicated that surface properties of the θ 2 layer predominantly controlled the machined surface finish. The θ 2 layer on the machined surface provided four types of feature; burnished, built-up residue, over-cut and smooth surface. The cutting forces depended on the rake angle and the fiber angle θ1/θ2 as same as the unidirectional composite. All cutting conditions presented built-up residue which consists of broken fiber and matrix around the fiber on the machined surface. Measurement results indicated that break down percentage, the weight percentage of built-up residue in the weight of the workmaterial, was significantly affected by the rake angle and the fiber angle θ1/θ2. However, break down percentage could not vary the values corresponding to the cutting force.

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The present study proposes a new method for calibrating the mean sensitivity of a precision angle sensor with a optional small measurement range without the need for an accurate reference instrument. This method can shorten a lot of time calibrated by the previously proposed method, and can calibrate the mean sensitivity of an angle sensor within an uncertainty limit, which is given by the, stability of the angle sensor in the measurement environment was estimated from thermal drift value. An angle sensor which has measurement range 500 microradian with nanoradian (nrad) resolution and stability of 3 nrad over 1 minute has been calibrated by the method. It was found that the repeatability errors of the calibrated mean sensitivity was approximately ±0.01%.

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It is essentially important to study deformation properties of an elastic blanket in offset printing in order to develop a more superior printing machine. This paper analyzes elastic deformations of the blanket due to rolling contact of the blanket cylinder with impression (or plate) cylinder, considering anisotropic properties and laminated construction of the blanket. Relations between contact stresses and deformations of the blanket are solved by using the two dimensional elastic theory. The numerical solution of the problem, which has considered rolling behavior of two cylinders and partial slip in contact region, is obtained by using an iteration procedure. Influences of a difference in nominal peripheral speeds between two cylinders in contact, the Young's moduli and thickness of each layer of the blanket, and the coefficient of friction in contact region on contact stresses and deformations of the blanket, are examined by the theory in detail. Experiments measuring deformations of the blanket are carried out. Calculated results are in fair agreement with those of experiment.

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This paper deals with an easy method for precisely evaluating the geometry of conically ground drill point from the coordinate data of many points on its flank surface. In the proposed method, the coordinate data are detected from CCD camera images of the drill point and the five parameters describing the geometry are estimated by fitting the data to the mathematical model of the grinding cone. The CCD camera simply gets outline images viewing from several different angular directions. As the parameter estimation method, Genetic Algorithm is used in which the condition of generation change and thee performance index are especially adopted for this fitting problem. The effectiveness of the proposed method has been verified according to the simulation and experiments.

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The system for manufacturing dental crown has been developed by applying CAD/CAM technology, to attain stable and sufficient supply of prosthetic teeth, which will be serious social requirement in the 21st century. In the report, non-contact three dimensional measuring device developed for the system is introduced. Fast measurement in reasonable accuracy for obtaining three dimensional images of dental cast model has been attained.

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To achieve the stable injection molding process, pressure profile trace control is developed. This control is one of the learning control system that is learned the material changes, mold changes and so on in the molding process. But adjustment method of molding parameter is not changed. Using velocity and velocity switch position, pressure profile is adjusted as suitable profile by try and error. To reduce this adjusting time, new function as pressure profile editing function is developed. This function is able to edit pressure profile directly like CAD system and traces edited pressure profile instead of reference pressure curve at good part produced. Difference between original pressure profile control and pressure profile editing function is velocity data existing or not. New function has to create velocity data and learns control gain. Modification of learning system is able to have good results of new function.

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This paper deals with a microrobot actuated by the click behavior of a spring strip with SMA wire. If the center of the spring strip is fixed, points will be deflected to a large degree by a small change in the applied force. These points are suitable for using at an output point to obtain large displacement magnification at a critical click point. The mechanism is available for displacement magnification and tangential displacement was magnified by a factor of 1.67 at the leg point and a factor of 5.20 at the tiptoe. The mechanism for the microrobot is expected to have many unique applications in the field of movement and feeding. The microrobot consists of the click buckling spring strip, a body, leg and tiptoe. Because tiptoe has nonsymmetry friction, the microrobot can move by creeping motion. A developed microrobot could creep in the air and underwater. The drive period of microrobot became short by cooling effect of water. The ratio of the drive period underwater to the drive period in the air is 1/5.82. The stroke of the tiptoe was 1.82mm at 2.0A and the mean crawl speed was 2.07 mm/s at 2.6A underwater.

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Accurate control of tools in precise machining requires force information to compensate for force induced deformation. Many, types of force sensors with strain gauges or piezo elements have been developed. However, usual force sensors may disturb a machining system because of their low rigidity. The authors propose an active force sensor which has an actuation capability and a detection capability for force and displacement. This sensor can improve its rigidity using the actuation. Prototypes of the active force sensor are fabricated and examined. It is confirmed that the prototype with a piezo device and two pairs of parallel plates is superior in terms of stability and sensitivity in force and displacement detection.

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In order to isolate the external vibration, the precise positioning stage is ordinarily mounted on the vibration isolated table. In this time, it seems that the positioning performance is greatly influenced by its table. However, ignoring the existence of isolated table, the position tuning for only the stage is carried out. Firstly, in this paper, the digital PID compensator is approximated to the continuous system. Then the closed frequency response calculated as a continuous system is compared with the experimental result. Confirming that the calculated frequency response macroscopically coincides with the experimental one, the stage positioning model can be derived. Secondary, the ultimate sensitivity method is applied to this positioning model. However, the desirable control performance is not realized. Considering this reason, it is clear that the isolated table is mechanically coupled with the stage positioning. Finally, the initial PID tuning method instead of the ultimate sensitivity method is applied to the positioning model. As a result, it is shown that the precise stage can be avoided from the dangerous runaway.

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