This paper describes the influence of physical properties of workpiece material on the difficulty in laser piercing through measurement of the absorption factor change with extension of the depth of hole pierced by a YAG laser. To measure the absorption factor, which is defined as the ratio of the power absorbed by the workpiece to the incident laser power, the inverse problem solution was utilized. Regardless of material properties, the absorption factor increases with the increase of the depth of the keyhole, and after reaching about 100%, the increase is stagnated and the absorption factor is saturated at 100% followed by a rapid decrease after the penetration. Thus it was concluded that the absorption factor in laser piercing is determined not by the intrinsic reflectivity of workpiece material but by the depth of the hole being processed. Consequently, difficulty in cutting copper workpiece by laser beam results from the high thermal diffusivity of copper rather than its reflectivity.

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This study describes laser heat treatment of steels using a YAG laser beam on-the-machine tools. An optical fiber has been used in order to transmit the laser light from a source to workpieces at this system. In the present report, experiments were carried out to research the quenching characteristics of various die steels using a YAG laser beam. As.a result, the influence of carbon and chromium in materials on hardening was clarified. Additionally, it is shown that laser heat treatment of pre-hardened steels is effective to increase the hardness of these materials. Tempering hardness of hot die steels is confirmed after laser hardening.

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Electron field emission properties of single crystal diamond particles have been investigated in order to lead higher emission current and to discuss the mechanism of electron emission. Emission current was measured by applying voltage between diamond particles and a glass plate anode coated with ITO thin film. Diamond particles were treated in plasma and by heat before measurement and placed in various arrangement manner on a metal substrate with conductive glue. As a result, higher emission current has been occurred from diamond particles treated with hydrogen plasma, that is supposed to form conductive layer on diamond surface. Moreover, direction of a tip of diamond particles towards the anode has led higher emission current. The emission current has increased with the number of diamond particles arranged and varied with the distance between diamond particles and the anode.

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Oil-air, oil-mist or micro-fog and oil-jet lubrication are used as lubricating system for high-speed machining center which is applied for the purpose of high-speed work and heavy duty processing. Injection hole leading to lubrication nozzles gives a resistance for the feed of the lubricant within air, but the countermeasure has not given concerning the air flow. Improvement must be given for the lubrication and cooling efficiency in order to increase in the rotational speed of spindle supporting by rolling bearings. This report describes some effects of two nozzle types which are debarred and polished by abrasive fluid or not, and of the supplied cooling air in -20° for the purpose of the decrease in temperature rise of the bearings. Main results are as follows : (1).The debarred and polished nozzle is more effective than without polishing concerning the mass flow rate of air in any pressures and lubricants. (2) Approach to the cooling air direct injection is effective for the temperature rise of the bearings. (3) Even if the perimeter of bearing is kept lower than the room temperature, the dew and freezing condition for the bearing have not occurred under -20° supply cooling air. (4) The temperature difference occurs on bearing outer ring when one cooling-nozzle is used, and the temperature difference of the bearing outer ring is changed by the distance between the cooling-nozzle and the bearing face.

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In machining operation, cutting and grinding fluids are generally used for cooling and lubricating workpieces at the point of cutting. These fluids often contain sulfur, phosphorus, chlorine or other such extreme-pressure additives to improve the lubricating performance. These chemicals present health hazards. This paper describes the results of a study of a new drilling method (Cooling-air-drilling-system). Cooling-air-drilling-system eliminates hazardous conventional cutting fluid, yet provides a high drilling performance.

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Surface plasma treatments of protecting polyimide films of semiconductor devices have been applied to improve adhesion between polyimide and molding resin. Ar, N₂ and 0₂ were used as plasma gases for surface treatments, and the difference of the surface properties for each plasma-treated polyimide film was studied The contact angle with glycerin decreased by N₂ and 0₂ plasma treatments. The electrical resistivity of polyimide surface decreased with the Ar plasma treatment XPS (X-ray Photoelectron Spectroscopy) measurements revealed that the Ar plasma-treated polyimde surface was carbon rich and N₂ and 0₂ plasma treated ones had large number of C=O and CN bonds. We believe that the carbon-rich layer makes the electrical conductive layer on the polyimide surface, and hydrophilic bondings (C=O, C-N) reduce the contact angle and improve adhesion between polyimide and molding resin.

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This paper deals. with the mathematical model for cutting forces by (A1, Ti)N-coated micro-grain carbide radius endmill cutter during endmilling of hardened steel used for dies and molds. A quadratic polynomial model was proposed for cutting forces based on response surface methodology by two variables of the engagement angle of cutting tool and the maximum undeformed chip thickness. In endmilling of hardened steel, the control of cutting forces is especially important because chipping occurs soon if severe cutting forces are present at the cutting edge. The control of cutting forces in profile endmilling which includes both straight and comer cutting, was very effective using this model. Furthermore, response surface form was applied for the case of wom endmill that had a cutting edge with large negative rake angle, and it was found that the control of cutting forces was also possible with some compensation even for the worn tool.

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Surface formation mechanism in a silicon-silicon homo-epitaxial molecules' growing process is carefully investigated by the help of AFM and RHEED. Observation of epitaxially grown surfaces showed that their crystallographic properties were improved much by having given a proper amount of thermal energy to adsorbed molecules through substrates, however, were not influenced by their density. On the other hand, the surface geometrical features were affected by both of the thermal energy and molecules' density, in addition, by a substrate crystal orientation. Namely, many nuclei were first formed and combined together with an epitaxial growth in the case of (100) substrate, however, many atomic layer steps were formed, extended and piled each other in the case of (111) substrate. Generally, the higher energy and lower density of adsorbed molecules could realize more coarse and larger nuclei and piled steps. These experimental results could be well explained by identifying their epitaxial growth mode first, then, taking either possible migration distances of adsorbed molecules and probability of their impingement into account.

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This paper describes the automated visual inspection system for optical transparent lenses which can recognize four kinds of surface defects. It is well known that the characteristic of transmitted light depends on the kind of surface defect of the lens. The influences of shading in image data must also be considered for image processing. Therefore, it is very difficult to develop an automated inspection system for the surface defects of lenses using image processing. If the features of surface defects can be recognized by a vision system, the nature of the defects will be clarified and the automated inspection system for the surface defects of lenses can be developed. Upon investigation, the optimum measuring condition was found to be one which can recognize four kinds of surface defects of optical lenses. Additionally, the new image processing algorithm, using the Concentric Frame Difference Method, can only recognize surface defects without the influences of shading. The kinds of surface defects can also be classified using the inspection system. The image processing algorithm, which is developed in the research, has great advantages. When using the image processing algorithm instead of the ordinary binary method, the gradation of defects is more greatly emphasized than the average image data. It is found that the visual inspection system, using the new image processing algorithm for the surface defect of lenses, is more effective in actual application.

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The aim of this paper is to develop welfare machine which has light weight and compact size, has interactive system in technique of human engineering in order to operate, and has actuator compliance control possible for movement to transfer viscosity elastic body as human being. Two 3 degree of freedom parallel robots of air pressure drive were developed as lift device in the previous paper, and the positioning control, the power control experiment were done, and a result for wish was provided. Transfer device by the air pressure drive that lift device is picked up in this report, and is carried to a destination is developed, and its effectiveness is confirmed by an experiment, and it is reported about algorithm to handle two 3 the degree of freedom robots which interactive, system on the basis of the recognition human engineering was developed to simplify operation of welfare machine, and the whole device is used for with lift device more to ligthen with one computer.

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Recently, it is required to improve the production efficiency and accuracy in the manufacturing factories, where many robots and manipulators are used. Therefore, it is required that the development of measuring method for position and attitude of moving objects with high accuracy. The main purpose of this study is to establish spatial coordinate measuring method using laser tracking station. In this method, spatial coordinates are calculated by the principle of triangulation from rotational mirror angles. However, the measuring accuracy of this method depends greatly on the mirror angle resolution. Thus, the laser tracking stations are combined with coarse and fine rotational mechanisms to achieve high accuracy spatial coordinate measurement over the wide range and dynamic measurement by using rapid-controlled-mirrors. The aim of this report is to realize the measurement error within 10μm in l×l×1m3 working space which is a common requirement in manufacturing industry. As the first step, the fine motion mechanism with a two degree-of-freedom was developed. In order to track laser beams to the targets attached on the moving object, the three piezoelectric actuators control mirror angles with high speed and high accuracy. Operating the fine motion unit, the measurement error was less than 10μm for both one- and two-dimensional coordinates measurement with the distance of 1000mm between tracking station and target or more. It was confirmed that the measuring system was applicable for the manufacturing industries.

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A compliance control system is designed for wire suspended systems. The kinematic and static characteristics of the systems are analyzed and a rigid manipulator model with some virtual springs at the tip is derived. After showing that both position controllers and force controllers are needed for compliance control of a suspended object, a way to design each controller is described. A compliance controller for a prototype crane with three wires is designed and the crane is used for automatic assembly and cooperation between the crane and a position-controlled industrial robot. The experimental results verify the effectiveness of the compliance controller.

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In this paper an object shape recognizing method which utilizes the information of a reflected ultrasonic pulse waveform is proposed. An electric spark discharge is employed as a non-directional point sound source. As for some simple shaped objects, theoretical and experimental waveforms coincide well with each other and it is proved that each waveform has characteristics based on the surface shape of the object. Four pairs of six type objects, which include several complicated shape objects, are adopted. An experiment of recognizing one among the six is carried out by using a pattern matching method. As the template for the pattern matching, both a power spectrum in frequency domain and a waveform in time domain are adopted and tested. The probability of recognition is better than 95% for the former and 98% for the latter, and it is proved experimentally that the information of a reflected ultrasonic pulse waveform in time domain is effective enough for the object shape recognition. It is also proved experimentally that this recognizing method can cope with the change of the orientation and the distance of an object, provided that the templates corresponding to the orientation and the distance are prepared in advance.

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This paper presents a new type stators for a spherical ultrasonic motor. This motor has three degree-of-freedom in one motor unit. A spherical ultrasonic motor has high performance such as it has high torque at low speeds, high holding torque, a gear is unnecessary and the motor can be driven silently. However, the output characteristics are different from general ultrasonic motors. For that reason it is necessary to investigate the vibration condition of the stator to improve output characteristics of the motor. In this paper a stator shape where the contact face is in the middle of the stator disk is examined using FEM. Experimental results shown an inprovement in the output characteristics about two times in comparison with the usual type stators.

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A limiting form can be derived by letting the weighting matrix of the state vector to infinity in a standard linear quadratic problem. Under the condition that the system is minimum phase it has been pointed out that the limiting form presents the solution to the output zeroing problem for arbitrary initial conditions. In this paper, it is shown that the limiting form is related to output zeroing problem for non minimum phase systems. Then it is proposed to apply the limiting property to control the manipulator composed of 2 links with a constrained condition. Simulation and experimental results show that the proposal control method is effective.

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A new control algorithm for a numerically controlled tapping is proposed. This algorithm uses two predictive controls. The Z-axis servo has a predictive control and the spindle response is also predicted. By doing so we achieve precise synchronization between the spindle-axis and the Z-axis not only constant velocity phase but also while accelerating and decelerating. An experiment using this algorithm achieved 625 rev/s² acceleration and deceleration, 6000 rpm maximum speed and 10μm precision.

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Curved micro-tunneling using small conduit pipes with diameters of 1m or less is recently applied in many construction sites. A new position sensing system to pinpoint the head of the first pipe has been come up with even when it cannot be seen directly from the base position. It differs from the traditional method of using the collimated laser beam, in that the diode laser with a large divergence is used as a point source of light and the direction of the point source of light is detected by using an objective lens and CCD camera. To apply this method to the position detection of the first pipe, the structure of the sensing unit and its detection accuracy were examined and the following results were obtained. (1) The structure using polarized beam splitter can suppress error led by rotating the sensing unit. (2) Through the simulation and some field tests, 20 seconds or less detection accuracy of direction angle was achieved.

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This paper proposes a design method of artifact that takes human satisfaction into consideration. The proposed design method combines design of experiments and satisfaction measures estimated by satisfaction measurement system with neural network based on measuring electroencephalogram. It is applied to a combination problem of design in the mapping from the functional space to the physical space. It is possible using this method to develop the artifact with which humans are satisfied, considering factorial effect of functions such as main effects, interactions and individual differences based on human satisfaction. The design method is actually applied to a combination problem between keyboards and displays of the personal computer, and is examined in terms of designing artifacts.

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This paper deals with personal information recognition in machine tool operation. First, a measuring system concerning a lathe was constructed. The system samples pulse, respiration, and galvanic skin response as biological information and revolution of handles and grip pressure changes as operative information. Next, the relationships between the processed indexes and personal information were investigated. A personal information identifying system, capable of recognizing, "concentration", "mental strain" and "less consciousness" in real-time as well as skill of the operator during machine tool operation was developed. The results of the experiments confirm the possibility of identifying the personal information.

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In case of uniformly distributed damping, the system can be expressed as real mode shapes and therefore the prediction of structural modification can be achieved with high accuracy. However in case of un-uniformly distributed damping, such as automobile suspension consisted of link, bush, the system should be expressed as complex mode shape, resulting less accurate prediction. In this paper, a numerical model is used to reveal the cause of such inaccuracy and then new algorithms are proposed to improve such inaccuracy. Finally by using proposed algorithm, an accurate vibration model of actual automobile suspension is obtained to be able to predict the change of vibration after structural modification.

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The paper describes a development of a diagnosing and operating system in which mutual cooperation between a system and an operator can be effectively used in decision making. Firstly, a concept of cooperation between the system and the operator was proposed. The authors discuss the cooperative method for plant operation and diagnosis. Then, the authors designed a framework of this system which is composed of three modules, namely a diagnosing module, an interface module and a supporting tool module. In this system, a knowledge base is represented by utilizing a fault tree and describing additional information for coopera-tive decision making. The authors implemented a prototype of the system for diagnosing human errors and malfunctions in a bio-process system. Finally, the availability of the prototype system is shown through simulated system operation.

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