For the efficient ope ration at a manufacturing factory required to produce a small size and various type of products, it is important to make a good schedule taking into account of jigs and machines assignment to jobs. This is because a tool and jigs are commonly equipped with machines. In this study, a pra ctical scheduler is developed, which solves job-shop scheduling proble m including the jobs and jigs assignment to the machines by use of a genetic algorithm (GA). A new c hromoso me representa tion is introduced into GA for applying it to the given problem and effective genetic operations are examined. Furthermore, a user-friendly graphic interface is reported that produces a suitable database for the operation. Numerical experiments verify that the proposed G A solves the job-shop scheduling in a practical time.

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In solid modeling systems, the stability of Boolean set operation algorithms is an important issue. The stability can be achieved by using the homogeneous processing, which is proposed by one of the authors, and the exact integer arithmetic. The variable integer data type can represent very large integers by changing the size of the date length. However, the increase of the data length of integers leads to the increase of the computation time. In geometric algorithms, the signs of determinants are necessary to modify the topological data structure. The previous method adaptively and repeatedly extracts 8 bits from variable integer data to detect the signs of 4×4 determinants. The previously proposed method detects the signs of determinants using an FPU. In this paper, a more efficient method is proposed for detecting the signs of 4×4 determinants by extracting 16 bits. The algorithm can detect the signs of 4×4 determinants faster than the previous algorithm.

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This paper proposes a method to detect crack defects that occur on edges of a semiconductor bare chip by using image processing and the wavelet transform. The one-dimensional profile that represents the unevenness condition on a side of a semiconductor bare chip is measured on the basis of the locations of four corners of the chip. Next, the wavelet transformed is executed to the profile. And, the crack defects are detected through the thresholding method to the amplitude and the frequency in the wavelet-transformed image. Experimental results show that the detectable rate of the crack defects reached 100% although a little overkill occurred.

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A controller based on inverse system has no countermeasure against modeling error of a control object. On the other hand, one of limiting properties of the linear optimal control by letting a weighting matrix of cost functional tends to infinity has disturbance decoupling property. In this paper, a trajectory tracking control method is proposed by combining an approach based on inverse system with limiting properties of the linear optimal control. The proposed method is applied to trajectory tracking control of two links robot manipulator. Comparative numerical simulations and experiments confirm effectiveness on trajectory tracking control.

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An antenna- stabilizing control device toward zenith direction employing strapdown 2-axis azimuth/elevation method was developed. In 2-axis method, a gimbal-lock that means lacking of control axis to pitch and roll of ship in high angle of elevation and large pointing errors occur. But, when a ship trembles, a horizontal line exists on a ship plane. Therefore, by coinciding an elevation axis with the horizontal line by rotating the antenna around an azimuth axis, and rotating the antenna axis to zenith direction around elevation axis, the antenna axis can be pointed to zenith direction. As an experiment of above control device, it was confirmed that pointing errors were less than 10° in 90% of working time.

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Skilled workers control the braze filler metal supply while simultaneously monitoring the formation of a metal molten area. This ensures high-reliability brazing of workpieces engaged in various states. In order to emulate the technique of skilled workers', an image processing method that monitors the formation of a metal molten area using a CCD camera is proposed. This method makes use of the fact that brazing is inevitably conducted in a reducing atmosphere. In a reducing atmosphere, the surface of a molten braze filler metal becomes a mirror having a high regular reflectance. A band pass filter and a light source so as to eliminate the burner flame light and infrared radiation light from the workpiece surfaces optically as interference lights in order to receive only the regular reflected light from the molten area were selected. The proposed method was applied to the automatic torch brazing of copper pipes in order to experimentally verify its effectiveness for high-reliability brazing.

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Servo motors are widely used in NC machine tools and robots. The control accuracy of such machines mainly depends on that of the servo motor. It is necessary to decide the accurate control model in design of the control system or to improve the control accuracy using CAD tool. The parameter identification of servo motor control system is usually done by using FFT analyzer. But the sampled data control is common in the recent servo motor system and the high performance microcomputer is used in the system. So it is convenient if the control computer is used for this purpose. In this report, an identification method using the delta operator is studied. In the discrete time control analysis Z-transform is commonly used, but it is known that it becomes unstable in the short sampling time condition so the delta operator is adopted in this study. In this method, parameters are identified by the least square method and Zero and Pole are solved by the Laguerre method. The order of the transfer function is decided by the Pole and Zero cancellation. The identification results are compared to FFT results and the effectiveness of Pole and Zero cancellation is confirmed experimentally.

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A scanning moiré method was previously proposed to measure shapes in real-time. In this method, contour lines of an object are obtained in a moment as a moiré pattern with sampling a grating image at every several scanning line. The disadvantage is that the image has jagged noise. In this paper, therefore, a new method to obtain a smooth scanning moiré without the noise is proposed. In this method, the image of contour lines is obtained by sampling process synchronized with the phase of a projected grating that is shifted continuously. It is called the phase shifting scanning moiré method. The principle, applications to shape and displacement measurements for actual objects and a real-time display system developped using this method are shown.

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In this study, with the aim of measuring the tooth profile error of minute module gears rapidly and precisely, a new measuring method that applies the optical cutting method is developed. This report considers about image processing method to get the tooth profiles exactly. Applying the Laplacian filter to the optical cutting images grayed into 256 levels has effect of emphasizing edges of image, and values of the threshold level become less effective to get binary images. Consequently, the medial lines of the images also can be extracted from the binary images in independence of the threshold levels. This could improve stability and reliability of measurements.

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The sliding leadscrew is a machine element used most generally in positioning technology. However, because of excessively discontinuous characteristic of friction between a male screw and a female one, it becomes an improper element for ultra-precision positioning. This study aims at improving such negative situation by a new technique. In the technique, axial displacement caused by deformation of an elastic element attached in series to a sliding lead screw is utilized for minute positioning motion under a full-closed displacement control. The deformation generated is adjusted by friction torque within maximum static friction. As the first report, this paper deals with friction characteristic in a sliding lead screw which must be basically known for this technique, and the structure and design of the elastic element. From experiments simulated to the case, it is confirmed that usable state of static friction exists clearly in use of lubricants for positioning. Experiments about function of the elastic elements equipped in a positioning apparatus show good results nearly as expected and possibility of ultra-precision positioning at nano-meter level.

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A new shape measurement method of rough surface is proposed. The method utilizes a radial shearing interferometry consisting of two zoom lenses with different magnifying powers and a laser diode being able to change its wavelength in a small range less than 0.1 nm. The radial shearing interferometry, known as a kind of common path interferometer, is capable of obtaining a very stable specklegram even under normal vibrational circumstance. From the specklegrams two phase maps corresponding to two slightly different laser wavelengths are extracted. The difference of phase values between two maps is nearly independent of random speckle phase, but depends on optical path differences. Then shape of the rough surface can be calculated from the two phase maps through the optical path differences. The validity of the method is experimentally demonstrated.

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A high-precision position and orientation localization system for an indoor mobile robot, which utilizes non-directional ultrasonic sensors and radio frequency wireless communication, is proposed in this paper. The transit times of the ultrasonic pulses from a transmitter attached to the robot to four receivers located on the ceiling are measured, and the transmitter's position is obtained by a simple triangulation principle. An electric spark, which works as a non-directional point sound source, is adopted as a transmitter. Since the transit times are obtained by a subsystem set on the ceiling, a measurement demand signal and transit times data are sent via wireless communication between the robot and the ceiling. A position measuring method proposed in this paper estimates in real time both the delay time of wireless communication caused by the modulation process and the sound velocity in the measured space. Static position accuracy of this system is experimentally inspected. It is proved that the accuracy is several mm and fairy good compared with other systems using image processing, etc. The developed system is mounted to a mobile robot and practical dynamic position and orientation accuracy is also inspected.

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The production of prototype of new LPCVD using lamp heating and its study of the characteristics of polysilicon film deposition were reported. When a micro machine is produced using polysilicon film deposited with this equipment, we will need to know the mechanical characteristic of this film. The conventional measurement methods of mechanical characteristics of films are not suited for thick film deposited using this equipment. So, first a suitable bending test, mothod in thick film were proposed and then Young's modulus of the polysilicon film deposited by the new LPCVD by the method were measured. The results of this study are summarized as follows; (1)The large bending test method is useful for measuring the Young's modulus of the polysilicon deposited by the new LPCVD. (2)Reliability of this measurement method is about 90%. (3)The average values of Young's modulus mesured is 121.4±7.1GPa.

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Clearance between anode can and gasket is evaluated by finite element method. First step of the analysis is to get contact stresses between gasket and anode can as axis-symmetric elastic deformation. Young's modulus of nylon from which the gasket is made is estimated from stress strain curve and from stress relaxation test data of nylon test pieces. Loads and boundary conditions are decided from difference between the shape of gaskets in the batteries and taken out from the batteries. In result, maximum contact stress is about 200MPa on periphery of anode can. Second step of the analysis is clearance estimation between gasket and anode can of which surface is modeled by an isosceles triangle shape. Relation between contact stresses and clearances is given. In macroscopic, no clearance exists near the periphery of anode can. Scratch shape on the anode can is important. If the ratio of depth to width is over 0.1 times, clearances exist in 200MPa. In electron microscopic observation, sharp scratches exist in the surface of anode can. Therefore, as the time the battery is made, only microscopic clearances exist, and no macroscopic clearances exist, between the gasket and anode can.

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A new patterning method of an optical rotary encoder gratings is proposed and tested for higher precision and higher rotational speed more than 30000 min^-1, which marks the grating patterns directly on the metallic shaft of an air spindle by using YAG laser marker. It is pointed that the second harmonic generated YAG laser wave is more effective for this application rather than the fundamental wave. The experimental patterning system applies a precise speed control system using a flywheel and the PLL (Phase Locked Loop) speed control system with the unique error compensation. The validity of this method is proved from a microscopic examination of the patterned gratings and the regeneration of the encoder signal with a standard optical detector.

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This paper presents a design method of acceleration and deceleration commands for a feed-drive system of NC machine tools. In general, the design method of such commands is in a black box, and has not been opened. However, it is important to make clear the design method in order to get high motion accuracy of the feed-drive system at high feed speed. In this paper, two cases of the typical motions are discussed; one is for circular interpolation motion, and the other is for corner tracking that is one of linear motions. In the circular motion, a constant acceleration technique is designed, and in the linear motion, an exponential acceleration technique is designed. From the experimental results, the improvement of the circular and comer trajectories and the effectiveness of the proposed design methods are confirmed.

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This paper proposes a novel fabrication method for 3-D microstructures using surface-activated bonding (SAB) of thin films. This method is a kind of layer manufacturing method for metallic or dielectric microstructures with an accuracy of sub-micrometers. In our method named FORMULA (Formation of μ-structures by lamination), all sliced patterns for microstructures are first formed on a donor substrate at the same time, then they are transferred and laminated onto a target substrate using SAB in a vacuum chamber. The shape and thickness of each pattern have high resolution because of photolithography process. By using SAB for laminating these patterns, metallic or dielectric films can be strongly bonded at room temperature without glue. FORMULA is experimentally verified by demonstrating batch transfer of aluminum film patterns and lamination of these patterns onto the target substrate. Micro gears, multilevel binary optics, and 3-D photonic crystal are considered as promising applications of this method.

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This paper deals with the cutting condition determination method for drilling several workpieces, especially when the hardness of each workpiece is different and unknown. The proposed method determines the initial cutting condition based on the nominal cutting characteristic for the material stored in the database, and identifies the cutting characteristics while cutting, then updates the identified cutting characteristics in the database. This "learning cycle" optimizes the cutting condition for the material with unknown hardness. The simulated and experimental results show that cutting time is reduced safely by about 40%.

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To realize precise atomic-scale mechanical processing using the AFM tip, wear of the tip must be reduced. An atomic-scale wear-resistant tip coated with hard films was fabricated. To produce the 1-nm-deep nanoslider, the processing properties of lines and spaces, and cross grooves fabricated on a layered crystalline muscovite mica surface using a cubic boron nitride (cBN), diamond-like carbon (DLC), titanium nitride (TiN) coated and silicon tips (radius less than 50 nm) were investigated. Fundamental profile processing properties of lines and spaces were evaluated at first. To clarify how narrowly a line interval can be processed, the processing period of lines and spaces was changed under the conditions at which mica with a 1-nm-deep groove can be formed. CBN coated tip enables more precise and finer processing than the other tip, and can yield nearly 1-nm-deep grooves at 50 nm periods. To form nanosliders supported by van der Waals force, narrow lattice grooves were processed using a cBN coated tip. By these processes, nanometer scale sliders with a nearly 50-nm-square area supported by van der Waals force, have been created. The behaviour of nanometer scale sliders after tip action is evaluated by examining the surface profile change. At a low load, a cluster of atoms on the central part of a nanometer dot moved to right by shearing at a depth of 0.7 nm, and were transported partially and irregularly. At a high load, most of the dots, acted upon by the tip, moved as one body.

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Conventional machining processes, such as turning, grinding, or lapping are still applied for many materials including functional ones. But those processes are accompanied with deformed layer, so that machined surfaces cannot perform original functions. In order to avoid such points, Plasma CVM (Chemical Vaporization Machining) has been developed. Plasma CVM is a chemical machining method using neutral radicals, which are generated by the atmospheric pressure plasma. By using the high-speed rotary electrode for generating the plasma, the machining efficiency which was equal to the mechanical machining method was achieved. Furthermore, generated plasma is localized around the electrode with effect of high-pressure atmosphere, so good spatial resolution of machining is also achieved. The defect density of machined surface is very low, and it is equivalent to the chemical etching.

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In this study, the authors have experimentally investigated into cutting performance of a new drilling method (to be called step vibration drilling or SVD hereafter) which was applied to drilling process of difficult-to-cut materials. In the experiments the authors have made a drilling apparatus consisting of a tool spindle and a workpiece table which can be moved with a step vibration mode. Drilling experiments have been carried out using the apparatus and JIS twist drills having a diameter of 3mm to evaluate the performance of the method for various work materials such as high-carbon steel (S50C), stainless steel (SUS304) and beta-titanium alloy (Ti-15V-3Cr-3Sn-3A1). The results obtained with the SVD method were better than the conventional drilling method and equal to those obtained with the conventional vibration drilling or CVD method in terms of drilling performance such as precision in the inner diameter of drilled holes and the ability to prevent the occurrence of burrs around the hole exit. Moreover, the tool life in the case of SVD was much improved over the CVD method, because the former could prevent chipping of the tip of a drill which usually occurs in CVD.

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