[in Japanese]

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The present paper deals with possible construction methods of three-dimensional shapes based on the nesting behavior of paper wasps. Paper wasps can construct combs of hexagonal cells with a regular arrangement. This paper describes observation and analysis of such nesting behavior. Observation results show that characteristic movements of antennae and nesting behavior, so called “taxis”, are used in determining how to shape the nest. Construction experiments are conducted to ascertain the relationship between constructed shapes and construction algorithms based on the nesting behavior. The results are as follows : 1. Using base shapes as a guide mark, construction algorithms of threedimensional objects based on the movements of sensors and simple moving rules lead to the construction of similar shapes and different shapes. 2. The movements of antennae and behavior, so called “taxis”, are used in determining how to shape the nest.

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Semiconductor chips for flip chip attach assembly are placed on a module board by the chip placement tool. The paper proposes the method for detecting locations of circular pads on the module board using the Hough transform to automate alignment process of the chip placement tool. The center position of each circular pad is calculated using accumulated values in a parameter space for Hough transform. Directions of edge points in an image are used to reduce the number of voting processes to the candidates for the center. As the result of performance estimation, alignment accuracy met the system requirements which need ±7μ m as x and y directions and ±0.2 degree as the rotation angle.

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RECS (Robot-Environment Compromise System) means the technology to compromise the robot and environment in order to increase the robot performance. In near future multipurpose robot unlike industrial robot is indispensable for social needs, welfare robot for example, and this type of robot requires high robot technology. However we cannot hope the establishment and practice of this high technology with enough reliability in near future. RECS makes it possible to develop the practical multipurpose robot by setting the environment so as that the robot can recognize and act skillfully to the object needed. In this paper RECS concept is proposed, and the advantage, limit of change of environment apt to robot, new robot technology uniquely for RECS are made clear. Indoor mobile robot system is developed according to the RECS concept, and experiment proved the practicity of RECS.

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NC (Numerical Control) lathes with two turrets are often used to achieve high efficiency of turning. To utilize them, it is very important to determine an optimal machining sequence by considering simultaneous machining, since combinations of processes influence practical cutting time very much. But it is difficult for users to determine an optimal machining sequence, because the number of combinations is great. A method is proposed to divide machining areas so that simultaneous machining may be the most efficient. The strategy is to check balances of cutting time for possible combinations of simultaneous machining and divide machining areas so that ill-balanced combinations may turn out well-balanced ones. After cutting directions of machining areas are determined, a balance table is generated. It classifies combinations into well-balanced ones and ill-balanced ones. Machining areas in ill-balanced combinations which require longer cutting time are divided so that cutting time of both areas will be nearly equal. Experimental results show that the method can generate NC programs with shorter cutting time than the conventional one does. The largest reduction in cutting time for the charts used on the experiments was 57 percent.

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In the previous report, the inchworm movement method using fine and coarse positionings was proposed by the authors. The experiment results showed that the inchworm movement method positioning had an over 100 mm stroke with 2.5 nm resolution and no backlash, and that the positioning was valid not only for point to point (PTP) control but also for continuous path (CP) control. However, there was interference between fine and coarse positionings, fine position error resulting from coarse positioning velocity discontinuity, when positioned by CP control. In this report, the new CP positioning algorithm of the inchworm movement method, in which coarse positioning command is continuous in velocity, has been proposed. The software servo that fine and coarse positionings are moved together by a new inchworm movement method algorithm makes it possible to reduce the interference.

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In three dimensional measurement system using the gray code projection, this paper proposes the technique for improving the reliability of the space encoding method. This space encoding method can measure the object under the illumination, the colored surface of object. The measurement space is encoded to 256 spaces by four gray level patterns. These patterns are projected by liquid crystal color projector, and are taken by CCD camera. When measurement area is 160 mm × 130 mm, measurement accuracy of this system is 1 mm, and the standard deviation is 0.41 mm in the horizontal cross-section, 0.34 mm in the vertical cross-section. It is shown that this method can measure colored object, by measuring the colored plaster figure in the dark and under the illumination.

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This paper presents a new method to transmit signals of transducers placed on a rotating machine element such as a gear shaft with infrared light. Light emitting diodes (LEDs) are placed at the circumference of the shaft instead of the end of it. And externally placed photo diodes (PDs) receive the frequency modulated light emitted by LEDs. Optimum numbers of LEDs and PDs are investigated for perfect signal transmission. Then the proposed way has been confirmed by a prototype of optical signal transmission system. It enables the signal acquisition from arbitrary point of a rotating element since it makes free from the difficulty of wire feeding. In addition, multichannel signal transmission is also realized by multiplexing method.

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In this paper, the authors evaluated the angular motion for air spindle by way of vector method which has been developed by the authors. From two vectors of radial displacement at the same rotating angle on two planes of different height, the directional cosines of rotating axis are calculated. It is made clear that this directional cosine method is able to confirm the behavior of anguler motion of the air spindle. Furthermore this paper proposes an information on the tilting motion of spindle axis and the spacial phase delay of rotating axis.

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This paper presents a new self-calibration method for calibrating the linearity error of two dimensional displacement sensors. By using this method, the linearity error can be calibrated accurately without using any other accurate calibration reference. This method utilizes the special feature of the two dimensional displacement sensor so that the self-calibration can be realized easily and effectively. In this paper, the proposed method is applied to calibrate two dimensional position-sensing devices (PSD). A calibration system, which consists of only a laser diode, an X-Y stage and a two dimensional PSD, is constructed. The laser diode is placed on the X-Y stage, and the PSD is fixed spatially. The laser beam from the laser diode is used to scan two-dimensionally the surface of the PSD by moving the X-Y stage. Two kinds of PSD were calibrated using the calibration system, and the experimental results confirming the effectiveness of the proposed method are presented.

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A high resolution and wide measuring range surface roughness measuring system based on dual servo STM (Scanning Tunneling Microscope) has been developed. STM is very effective method for surface roughness measurement, owing to its ultra-high horizontal and vertical resolution. But STM is not sufficiently useful for various industrial applications, because of the small measuring range especially in the direction vertical. Newly developed dual servo STM has a PZT driven double-compound parallel springs with 60μm travel for coarse mechanism and a PZT for fine mechanism. Both coarse and fine mechanism are controlled simultaneously to get stable tunneling current between measured surface and probe. In this report measuring principle and basic characteristics of the dual servo STM are described. Then it is used to measure surface roughness of machined workpieses and the results are compared with data obtained by a stylus method.

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This study describes the development of an optical noncontact measuring instrument for the 3 -D shape of an object with a free-form surface. The optical sensing system of the instrument proposed in the previous papers detects the depolarized component of backscattered light from the object surface excluding specularly reflected light. Diffusive object surfaces and metal surfaces with both specular and diffusive components can be measured by using the system. However the detectable range in height is narrow for one point measurement and the system is roughly positioned by manual operation at steep slope and edge portion of the object surface to be measured. In this paper, a low resolution optical system for expansion of detecting range has been developed as well as the high resolution optical system already reported. Therefore a new optical sensing system can possess both rough and fine positioning functions and automatically change them each other. The Lew sensing system is wider in detectable range and shorter in measurement time than the previous sensing system. Using the new sensing system the standard deviation of measurement errors can be evaluated 1.4μm in the case of the diffusive object surface having white color and less than ±83° in inclination angle.

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A new method for controlling helium gas (He) pressure and concentration in X-ray steppers has been developed. The mask chamber to which an X-ray mask is attached must be filled with pure He gas to use the X-ray effectively, and the pressure difference between the inner (He) and outer (air) surfaces of the mask must be controlled to a level below 0.005 mmHg to keep the mask deflection within 1μm. The key feature of this control method is the utilization of the density difference between air and He (γ_A-γ_H). He gas regulated at 1 mmHg (gauge pressure) flows into the mask chamber through a small diameter orifice. To compensate for the pressure drop ΔP in the discharge pipe, the gas is discharged to the atmosphere through a pipe kept at a location, that is h= ΔP/ (γ_A-γ_H) higher than the mask center. He concentration of more than 99.95% and the pressure difference of less than 0.002 mmHg were achieved in the X-ray stepper.

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The load distribution and life formula for LMBG (Linear Motion Ball Guides) system constructed by two guide blocks on one rail are derived and the theoretical analysis is carried out concerning the basic dynamic.load ratings which are considered with the fluctuations of load distributions, the effect of linear strokes, load eccentricities, conformity factors etc., then the fatigue life test series made up two crowning patterns of guide block raceways are carried out. The results are as follows : (1) The basic dynamic load ratings of LMBG system increase in accordance with the increase in the strokes and decrease in the conformity factors, and decrease in accordance with the increase in the load eccentricities. (2) Theoretically, the probability of flaking occurrence in the guide block raceways is greater than that of the rail, because of the differences between the number of stress cycles and the basic dynamic load rating for the block and rail. (3) In the experiment, the most flaking occurrences are from the rail raceways due to the materials difference from the block and rail. (4) The life test results fit well to the 3-parameter Weibull distribution which is introduced to the location parameter i.e. the minimum life and the Weibull slope m=10/9. (5) The estimated basic dynamic load ratings from two test series are 50% and 90% for the theoretical values, respectively.

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Machine tool characteristics such as machine vibration and stiffness have a large influence on cutting processes. Cutting processes, therefore, are dependent on machine tool characteristics as well as the characteristics of cutting tool and workpiece. This paper describes autonomous operation planning that can optimize cutting operation with evaluating machine tool characteristics. Machine tool characteristics that have an effect on tool wear and surface finish are evaluated by adaptive prediction. Adaptive prediction, which can predict cutting processes by analysis and neural network, evaluates the characteristics with the parameters used for the predictions. Adaptive prediction is carried out exclusively on two machine tools, and then it enables us to recognize the difference of machine tool characteristics. Autonomous operation planning with adaptive prediction allows us to determine optimum cutting conditions for each machine tool. This leads to the reasonable usage of machine tool in shop floor. It is shown that machining scheduling with autonomous operation planning is efficient in the assignment of six jobs to two machine tools.

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Surface microstructural properties such as surface roughness, and grain size have a decisive role in increasing the corrosion resistance of the materials. This study is mainly focused on characterization of the surface of oxide thin films using atomic force microscopy (AFM). These films having a thickness of about 500 nm, had been processed using ion-beam sputter deposition, and ion-beam-assisted sputter deposition (IBASD) methods. The following conclusions were made. i) The surface roughness caused during deposition was about 1 to 5 nm, depending on the film material and assisting beam current density. The surface roughness of Al₂O₃ was less than that of TiO₂ in most cases. ii) The roughness of the surface directly reflected that of the initial surface. However, the ion beam current which influenced the poly-crystallization of the film material, also contributed to the increase in surface roughness. This was more significantly observed in the case of titanium dioxide prepared under irradiation of 5μA/cm² ion beam.

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This paper deals with a monitoring method for lapping process. First, a lapping jig was newly proposed, taking account of loading the piezoelectric ceramic sensor and the electric circuit and applying to a conditioning ring type lapping machine, in order to detect acoustic emissions caused by mechanical actions of abrasives. Specific power peak level in the acoustic frequency region from 1 kHz to 3 kHz was found to be sensitive to changes of lapping conditions. Then, optical glass BK7 and carbon steel S45C as work materials were lapped with the slurry of SiC abrasives suspended in water and cast iron lap, and the measurement of specific power level was carried out. When using the finer abrasives, the lower level was obtained. And when abrasives were crushed down with elapsed lapping time, the power level also decreased. Meanwhile, high power level was detected when the coarse abrasives were added in slurry. Rather higher power level appeared under lower lapping speed and high pressure conditions. Moreover, the power level is closely connected with the surface roughness as a mark of stock removal, and it was evident that the surface roughness on lapped works could be given by measuring the power level on lapping. Consequently, there is a sufficient prospect for establishing the monitoring method in lapping by using piezoelectric ceramic sensor.

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A new method of fabricating ceramic thin films called Interface Controlled Vapor Deposition (ICVD) has been developed for the purposes of (1) control of the film's crystallinity and orientation, and (2) low temperature fabrication. The ICVD method makes these capabilities possible by strictly controlling the interface conditions between the substrate and the thin film. As one way to control interface conditions, this work introduces ion beam irradiation during fabrication of the interface modification layer by a vapor deposition process. This method was applied to the fabrication of zirconium nitride (ZrN) film. The ICVD method consists of two steps. In the first step, the modification layer is formed by evaporating zirconium with simultaneous nitrogen ion irradiation. In the second step, evaporation alone is continued in a nitrogen atmosphere in order to deposit a second layer. Using this method, ZrN film with good adherence and crystallinity is fabricated at room temperature, and its crystallinity and orientation can be controlled.

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This article presents the recent results from the study conducted by the authors on the application of giant magnetostrictive material. Tb_0.3Dy_0.7Fe_1.95 is used to develop a novel pump which is able to feed at constant rate under high pressure. Two kinds of methods are employed for comparison purpose to fabricate the giant magnetostrictive material; Bridgman method and powder metallurgy method. The performance of the pump using each sample is closely evaluated and compared with each other. Prestress dependency of the magnetostrictive rods is also examined to illustrate distinctions between the two methods. It is found that the rod manufactured by powder metallurgy method shows less prestress dependency than that based on Bridgman method while the pump equipped with the latter sample yields a higher flow rate than the former does. It is also verified in terms of the efficacy of giant magnetostrictive materials on pumps which implies possible futuristic applications in human bodies by downsizing its power transmission mechanism.

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