This paper presents an investigation into processing technology of ultra-thin quartz with abrasives. Quartz plate is processed industrially with double-sided lapping equipment. The thinner thickness of quartz, the larger obtained frequency. However, it is impossible to make quartz plate with a thickness of less than 30μm due to the distinct limit in the thickness of the carrier. In this experiment, single-sided lapping equipment was used for lapping and polishing to create ultra-thin quartz. It was noted that protection of the quartz edge and the flatness of the lapping plate and polishing pad are important. Therefore, an iron washer was used to protect the quartz edge and the lapping plate and polishing pad were made flat by facing. During the experiment, this flatness was maintained by placing a conditioning ring with a weight of 3kgf on the lapping plate. By maintaining the flatness of the lapping plate, a high reproduction was achieved. During polishing, the rotating speed was varied and a nonwoven fabric was used with a slurry containing Si0₂ with 0.5μm in diameter and CeO₂ with 0.7μm in diameter. As a result, a quartz sample with a thickness of around 10μm was produced.

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The depth of cut and cutting speed effects were examined In order to clarify the precise lubricant applying effect The experimental results indicated that the microvickers hardness distribution in the region to be cut and the cutting speed markedly controlled reduction percentages in the cutting forces. It is concluded that the lubricant applied to the pre-cut surface reduced friction in the lamella structure, which results in easier shear deformation under high normal stress at the shear plane.

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Oil-mist lubrication system supplies very small quantity of oil with compressed air to endmill from a nozzle. Vegetable oil without any harmful substance is used in this paper. Thus troubles such as environmental pollution or deterioration of working environment caused by using large amount of cutting fluid are hardly caused by using this lubrication method. In this paper, this oilmist lubrication is applied to high-speed milling of S45C steel in which cutting speed is over 2000 m/min. Then effects of its lubrication on tool wear are discussed. As a result of cutting tests, by using proposed oil-mist lubrication, tool wear becomes small compared with the case of no lubrication if cutting speed is lower than 750 m/min under the settled cutting conditions. It was also clarified that oil-mist supplying position affects tool wear. Tool life becomes longest when oil-mist is supplied at the disengage point in milling. And tool wear suppression effect of oil-mist becomes larger if the quantity of oil supplied from the pump increases up to 0.5mL/min. But tool wear rate doesn't become small if more quantity of oil-mist is supplied.

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Burr is formed at workpiece edge in most metal cutting methods. The burr formation mechanism in milling is, especially, complicated because of geometric variety of tools and workpiece shapes. Burr formation is considered to be plastic deformation of workpiece edge. One aspect of dominant factors is workpiece shape, which has effects on plastic deformation, and another aspect is deformation process in burr formation, which is classified into "sheared" and "hinged". These processes are controlled by exit order of cutting edges from the workpiece edge. In this study, burr size which formed with various geometry of tools and workpiece edge is measured. Moreover, the effect of in-plane exit angle on side burr size was analyzed with a finite element method (FEM). As the results, it was found that the in-plane exit and radial rake angle have great effect on both exit and side burrs in face milling because these formed the various deformation area at workpiece edge. Burrs formed on the hinged side possibly grow because the workpiece material, previous burrs or cutting chips remains on the burrs. To control the burr size and shape, it is important to control the deformation area at workpiece edge by in-plane exit angle and radial rake angle.

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In this paper, a new touch sensor which can detect the contact point of grinding wheel with the workpiece at the beginning of grinding process, is developed on the basis of the spouting phenomenon of grinding fluid from the grinding wheel surface during the wheel approach. Main conclusions obtained are as follows : (1) The developed touch sensor is a thermal sensor which detects electric resistance changes of nichrome thin film incorporated in a bridge circuit. (2) With the touch sensor the wheel approach can be detected at 42.9μm before the contact point in this experimental conditions of plunge speed Vp=2μm/s and grinding fluid flow rate Q=15L/min. (3) It is made clear that the unique phenomenon, in which the spouting volume of grinding fluid from the. grinding wheel surface increases, occurs as the wheel approaches towards the contact point.

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This paper describes the fabrication process, internal stress relaxation and micro-forming of a thin film metallic glass (TFMG). Metallic glasses are kind of amorphous alloys having suitable characteristics for micro-mechanical systems as isotropic and homogeneous. Moreover metallic glasses softens in a certain temperature range called the supercooled liquid state, which makes metallic glasses easily formed into a three-dimensional shape. In this paper, Zr based TFMG was deposited by RF magnetron sputtering. The TFMG had the supercooled liquid state whose temperature width was 61K. Its physical properties such as density, corrosion resistance were measured as well. Micro-beams of TFMG were made by the rift off process. Although, the produced micro-beams buckled because of the internal stress by sputtering, this internal stress was relaxed by heating TFMG to the supercooled liquid state. Finally, TFMG micro beams were softened and micro-formed by heating it into the supercooled liquid state. The deformation mechanism was analyzed using a bimetal cantilever model and calculated results coincided with experimental ones.

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This paper reports study on manufacturing technology of a spindle motor which used for 120MB FDD. This motor is an inner rotor type which is designed a linear shaped dividing block core connected by thin bridges. In coil-winding a linear shaped block core is wound by several nozzles. After winding, the linear shaped block core is bent as a similar conventional circular stator. The influence to the motor characters by the dividing block core with magnetic analysis is invested. The flat spindle motor for 120MB FDD was developed and high manufacture-ability was realized.

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In order to drive AGVs autonomously, an AGV must interpret peripheral AGVs' behavior to avoid collisions with them by itself. Knowledge of this interpretation through AGVs' experience is so called a communication protocol. This paper presents the new method to acquire the communication protocol between the AGVs by machine learning. Q-learning is adopted as machine learning. Once the AGVs acquire the communication protocol, they can autonomously move such that they avoid collision between the AGVs when they meet each other, and collaborate with their velocity between themselves when they drive in the same direction. Numerical experiments are performed to verify that the proposed method brings the AGVs to acquire the proper communication protocol and that the acquired protocol instructs the proper behavior to the AGVs.

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The increase of total demand of dental prosthetics will be an important social issue in the 21st century. The system which can produce prosthetic teeth in industrial way by applying CAD/CAM technology has been developed. 24 dental crowns were designed and manufactured using the new system and set in patients' mouths. All crowns have satisfactorily functioned. The time of total manufacture will be possible to be settled within 60 minutes, which is comparable with conventional method.

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A high precision mounting robot system consisting of SCARA robot and fine motion mechanism attached to the end effector of the robot is being developed by authors, This paper introduces basic concept and design specification of the system, and describes the design and capability of developed X-Y axes fine motion mechanism for this purpose in details. Developed fine motion mechanism is composed of piezo-electric actuator and displacement magnifying mechanism with elastic hinge. Detailed structure of the mechanism is designed by simulation based on FEM. Experimental results of positioning show the effectiveness of developed fine motion mechanism.

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Linear motor feed drives are considered as the ideal drives with no-transmission, no-backlash and smooth motions. But if they are applied to dynamically complicated machines such as machining centers or cantilever type XY robots, the servo systems are influenced by the structural vibrations. The vibrations inspired by tracking motion aggravate the motion and position accuracy. Some of them are detected by position sensors and destabilize the servo loop. This paper deals with the design method of stabilizing controllers for the linear motor servo drives under the influence of structural vibrations. The feed drives are modeled and analyzed taking structural vibrations into account, and stabilizing controllers are designed based on the modem control theory. A reduced order controller is also designed and compared to the classical PI compensators in terms of servo characteristics. Observer based full state feedback controller and local state feedback controller are found to be effective through simulation and experiment.

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In order to realize precision grinding, in-process measurement of grinding wheel wear is required. No method for the inprocess measurement of the wear of a grinding wheel with high accuracy in wet condition has been studied because grinding fluid causes a difficulty in measurement. In this paper, a measurement method by hydrodynamic pressure around the grinding wheel caused by grinding fluid is proposed for measuring the wear amount of a grinding wheel. A pressure sensor is set around a grinding wheel. The grinding fluid is supplied to the gap between the grinding wheel and the sensor. Because the viscous fluid is dragged into the clearance between a grinding wheel and a pressure sensor, the hydrodynamic pressure is generated. The relation among hydrodynamic pressure, gap distance and rotational frequency is examined. With the increase in gap distance between the sensor and the disk, the hydrodynamic pressure decreases. By using the measured hydrodynamic pressure, the distance between the sensor in the gap and the grinding wheel can be calculated so that the grinding wheel wear can be measured. The maximum error in using grinding wheels is less than 2 μm in dispersion. By calibrating the relation between hydrodynamic pressure and a gap distance, the measurement can be made towards the actual grinding wheel.

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A grating projection method using a stereo microscope is developed to provide a surface profile measurement. The phase shifting technique is applied to attain high accuracy detection of the projected fringe. Then, to overcome 2π phase jump caused by large height, contrast detection of the projected pattern is used. The contrast variation depends on the distance between sample and objective lens. This distribution is almost as same as an optical sectioning that is usually used in confocal microscopy. The fast reconstruction procedure is proposed to analyze the focused point from a few images. Moreover, this information is also available for the phase unwrapping of the phase detection. This method is experimentally verified by measuring a stepper specimen.

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A method of measuring the motion of a stage has been developed based on a Thru The Lens optics system. Images of the target, which has line & space patterns written on a Si wafer, are detected through the lens by a linear image sensor, which is synchronized with the output of the position sensor of the scanning stage. The displacement from the ideal orbit is measured by an image analysis method. This method has a fixed measuring point in contrast with the moving measuring point of a laser interferometer system, and the method is optimum for laser processing systems and LSI wafer inspection systems. Its accuracy was evaluated to be 10 nm p-p.

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In general, a robot arm has equal number of actuators to number of its joints, whereas a human extremity has an antagonistic pair of bi-articular muscles acting simultaneously on both joints in addition to the antagonistic mono-articular muscles on each joint. In the present study, mechanical properties of a two-joint robot arm equipped with three pairs of antagonistic Mackibben artificial muscles were examined theoretically and experimentally in terms of control engineering. The results obtained in this study demonstrated that the viscoelastic properties and the output forces developed at the end point of the robot arm were controlled independently in the task coordinate system. This might further suggest that, as to control of trajectory, position and velocity of the end point in the task coordinate system, open loop control instead of feedback control will be available in the muscle coordinate system, but not, in the conventional joint coordinate system.

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Both surfaces of fine ceramics used for electric parts are covered with, for example, a resin, a ceramic alumina or a solder. An automatic optical method for detecting cracks originating at the side faces of ceramic parts, the surfaces of which are covered with the above-mentioned materials, has been developed and is reported in this work. A laser beam is diffused into the specimen by illumination onto the side faces through an objective lens. When the specimen has a crack near the laser spot, the diffused laser light is reflected by the crack and the amount of radiant exitance near the crack is increased. The image of the side face is enlarged by the objective lens and detected by a CCD camera. It is clarified experimentally that it is possible to recognize the region surrounded by a close-ended crack wider than 20μm and longer than 351im, or an open-ended crack longer than 50μm, by detecting signals higher than the average level with the CCD camera.

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The purpose of this study is to propose a criterion to evaluate brightness uniformity of LCDs (Liquid Crystal Drystal Displays)For this purpose. it is necessary to increase the understanding of human sensibility to brgltlness uniformity: At first we, performed a kind of psychophysical method using CG patterns displayed on a CRT monitor. The result shows that the brightness gradients determine the degree of brightness uniformity. In the second step, brightness gradients and sensory scores by human evaluation were measured in uneven regions on LCDs. The gradients were calculated by digital image processing techniques. The sensory scores were quantified from experimental results by a kind of paired comparison method. A strong correlation (r²=0.90) is shown between the gradient and the sensory score. In the next step. parameters of gradient image histogram and sensory scores are measured for whole surface of LCDs. Strong correlation (r²=0.86) is shown between average gradient for whole surface and sensory score by the majority of testee and maximum gradient. agree with other testee (r²=0.71). Measuring error using the parameter is almost the same as human evaluating dispersion. By those experiments. it is shown that the brightness uniformity can be evaluated agreeing with human sensibility by image processing technique.

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Condition diagnosis of rotating machinery by the dimensionless symptom parameters of vibration signal has been widely used for the plant predictive maintenance procedures . This paper describes a new method to diagnose the plant machinery condition by the Information Divergence (ID) which is calculated from probability density functions of vibration signals. On the basis of the theoretical analysis, it is shown that the failure diagnosis sensitivity by the ID method is higher than by the one of Kullback-Leibler Information (KI). According to the information and the pattern recognition theory, a condition surveillance and a precise diagnosis method for rotating machinery by the ID method were also established. The availability of this methods has been verified by the experiments for gears and bearings condition diagnosis.

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