In this research, we developed a simulation system which can monitor the states of machine tools and predict the cutting load. The system is composed of a machine tool, CNC, and PC. The PC is connected to the CNC by a high-speed serial bus (HSSB). This system stores the state of machine tools at regular intervals in a database. The simulator of cutting load in this system predicts the cutting load from the stored machining load and cutting volume calculated from NC data. It can predict the cutting load at an error of less than 4% by this simulator.

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Work on constituting a flexible manufacturing system that can respond to high-mix very-low-volume production by using intelligence is proposed in this research. The intelligence is provided by a product agent. This report examines a method of realizing the negotiation function to determine the selection of the production machines for each manufacturing step and to obtain a schedule in real time through the negotiation among two or more product agents aiming to increase efficiency of the whole manufacturing system. Manufacturing scheduling was performed based on time for delivery.

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At present, Measuring machine such as coordinate measuring machine is widely used for design verification. However, such machine is difficult to use without enough experience and knowledge concerning design and manufacturing. Therefore, it imposes too much investment for Human Resource and leads to barrier for the customer to utilize. This problem is remarkable in the medium and small sized enterprise. So, in this paper, considering the possibilities of Human Resource Outsourcing, we proposed new business model employing internet technology that enables maker-customer communication by focusing on the actual condition survey of CMM user.

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The non repetitive run-out (NRRO) of rotational frequency of the cage is mainly caused by the diameter differences of balls contained in one bearing. In addition, it was known that the unequal orbital intervals of balls could influence the NRRO of rotational frequency of the cage. But there were few quantitative studies about this. In this paper, we investigated the influence of the unequal orbital intervals of balls on the NRRO of cage rotation by pulling out balls intentionally. It was clarified that the NRRO of rotational frequency of the cage became large if the difference between orbital intervals of balls was large.

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One of authors developed a complex lubrication system with an oil jet lubrication and an under-race lubrication system for angular contact ball bearings with dmn value < 390 million (dm = ball pitch circle diameter in mm, n = speed in min-1). In order to increase the speed limit of bearings, we have developed a new lubrication system. In this paper, the eco-friendly oil jet lubricated bearings and a lubrication system are introduced. The power loss and the temperature of the eco-friendly oil jet lubricated bearings are almost equal to those of the air-oil lubricated bearings under dmn value 250 million and the eco-friendly oil jet lubricated bearings with 70mm in bore diameter were successfully operated at dmn value 500 million.

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The detection of a rolling bearing fatigue failure had depended on the experience of the engineer, while recently the standard for failure detection has required the objective standard and many parameters have been suggested. This study used signal data of the compound sensing system developed by MSD Research Group and analyzed the acoustic emission and vibration from the viewpoint of statistical control of quality using Mahalanobis generalized distance. This report discusses that we could indicate objectively the nature of acoustic emission and vibration in analyzing the standard deviation of basic statistics that form the basis of parameters and correlation between the acoustic emission and vibration.

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This paper introduce the result of a fatigue life test date of Ball Bush which is a kind of linear bearing. Collected life data is arranged by log normal distribution, 2-parameter, and 3-parameter Weibull distribution. Fluid polishing is carried out for the outer sleeve raceway of Ball Bushe, and the life test result is compared with conventional Ball Bush which is not carried out fluid polishing.

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This paper deals with the Ball Spline fatigue life distribution under simultaneously applied radial load and torque. This life test rig automatically stopped by vibration sensor when flakings occurred. Life test data are plotted by log-normal, 2-parameter and 3-parameter Weibull distribution respectively. The results are as follows: (1) The life distributions of Ball Spline are well conformed to the 3-parameter Weibull distribution function with a Weibull slope m=10/9. (2) The flaking occurrences are almost from the end portions of outer sleeve raceway.

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The crowning provided at the both ends of the raceway of linear bearing guide block decides all sorts of bearing performances those are load capacity, rigidity and life etc. by its shape. For Linear Motion Ball Guide and Roller Guide which are the kinds of linear bearings, this report introduces the theoretical load distribution and the analyzed result of the various types of crowning given to the guide block.

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We developed a unique inline viscometer for continuous ink jet printers. The viscometer consists of a plunger moving vertically in a cylinder, a solenoid for raising the plunger by electromagnetic force, and a proximity sensor for detecting the position of the plunger. A viscosity can be calculated automatically by a free-fall time of the plunger from the top of the cylinder to the bottom. As the free-fall time is proportion to the viscosity of liquid, we can find the viscosity easily. Furthermore we cleared the factors of variation in measurements. And we designed the viscometer so that standard deviation was less than 5% of the measurement value.

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Assemble for miniature mechanism is used in precision mechanics and electronics generally. An optical fiber array is an optical communication device that consists of multi-core optical fibers and a V-grooved substrate. The demand for optical fiber arrays has increased significantly, it needs the mass production of optical fiber arrays. For automatic assemble of optical fiber array, a fiber must be put a precise position of V-groove. It is dependent on the friction coefficient of a optical fiber with the V-groove′s slope whether precise positioning can be performed. Vibration is effective in order to reduce the coefficient of friction. This paper deals with vibration effect for miniature mechanism assembling. The effect of the vibration for the positioning of fiber and V-groove substrate was examined using the experimental equipment.

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Electoro-Rheological Gel (ERG) was developed to overcome the defects in Electro-rheological Fluid (ERF). The ERG shows the wide range of shear stress variation in response to the applied electric field. To apply the electric field to the ERG, it is necessary to sandwich the ERG between plane-parallel electrodes. However, it is not convenient for the practical use to wire the both of electrodes for high voltage supply. In this study, the one-sided structured electrodes are proposed in order to simplify the structure of the wiring. The basic characteristics of ERG on one-sided electrodes are evaluated experimentally. The result shows that its electrodes provide almost same performances as the conventional plane-parallel type.

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In this paper,we examine the design manual of reduction of gravity load using the gas spring. Gas spring is effective in the mechanism that decreases the gravity load. Gas spring is small, has a small spring constant,and the change in the repulsion power is few. However, it has a different characteristic at the compressing and the extending. We should design taking the difference of the characteristic into consideration.

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Influences of the transverse vibration force in the long life region have been investigated. And a method to estimate a nominal stress caused by transverse vibration at the root of the first bolt thread has been proposed to generalize the loosening-fatigue limit of the results. The results show that the loosening-fatigue life significantly depends on the transverse vibration force. The estimated loosening-fatigue limit by the proposed method was in agreement with the value estimated from the axial fatigue limit of a bolt.

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An automatic electric power generator that utilizes self-excited rotation occurring under vibration has been investigated as a power supply for information devices. The amount of electric power of a rotated type generator increases by utilizing self-excited rotation. By the approximate analysis about self-excited rotation, we confirmed the condition when self-excited rotation occurs and deterimined the control methods of creating self-excited rotation and demonstrated the effectiveness of the control techniques. In addition we suggested two methods of high-efficiency power generation on the basis of occuring self-excited rotation and demonstrated the effectiveness of the methods.

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A new wheel mechanism of a snake-shaped robot adapted for moving in a complicated 3D environment is developed. The wheel consists of a torus shape of which the surface itself rotates around the larger diameter circle of the torus and moves toward the direction of the axis of the torus. The mechanism is studied and proved to be feasible and by constructing the actual model to work as is expected.

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In this paper, we present an algorithm of task assignment and motion planning of robots used in a palletizing system to pick parts on a conveyor belt. Because of high-speed and continual motion of robots, robot fatigue, which has the potential to bring the system to a halt, becomes a serious problem. To make an optimal algorithm considering robot fatigue and efficiency, we generate a state-action map via reinforcement learning, regarding the whole system an agent. Parts are assigned to the robots based on two simple rules. The robots then chose their optimal motion for pick-up or reassign the parts based on the map. By using the map, robot fatigue is restrained and consequently the efficiency of the system is improved.

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Nowadays development of the welfare robot is required in order to solve carer shortage because of an increase of aged people. As one of the application of the welfare robot which goes around home and helps aged people, the spreading and folding task of clothes after washing is focused. A special spreading bar for spreading clothes, a special tool and a special table for easy grasping of clothes are developed based on RECS (Robot Environment Compromise System) concept.

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In this paper, a home robot is developed based on RECS (Robot Environment Compromise System) concept. This concept aims to share the technical difficulties with robot and environment. In other words, RECS modifies the environment in order that the robot task would be possible or easy. In this research, it aimed to prepare the PET bottle beverage, and to open the door of a refrigerator to take out a PET bottle from it, and to open and shut the lid of the PET bottle with a supplementary tool for that was achieved.

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Nowadays, many mobile robots are developed to automate the cleaning task. The motion algorithms for cleaning task are roughly classified into two groups: planning type and reactive type. Reactive type algorithms are rather practical, and often used in commercial cleaning robots. However, when such a robot gets into a narrow area surrounded by obstacles, the robot cannot readily get out of the area. This causes the unefficiency of the cleaning task. Addressing to this problem, we propose a method to estimate the status of the robot using equipped sensors. We made a simulator to confirm the effect of the proposed method.

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At the previous annual meeting, we reported a newly developed turning method and its better energy consumption with less necessary time, compared to that of the traditional march turning-over method. However there was a remaining task to improve its first step in a more stable manner. We could successfully improve its first step motion and evaluated its energy consumption again.

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Planning of graspless manipulation is time-consuming because of its complicated calculation for mechanical analysis. In this paper, we present an improved method based on a probabilistic techniques, RRTs (Rapidly-Exploring Random Trees). The method is applied to planning of graspless manipulation where the manipulated object has three d.o.f., while our previous planner can deal with manipulation where the object has only one d.o.f.

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In order to manipulate an articulated robot, we must find a collision free path from the start configuration to goal configuration. The Probabilistic Roadmap method is one of most representative path planning methods. It constructs the roadmap which is a set of sub-goals and local paths. Based on this, it can find a path by connecting a start configuration and a goal configuration with the roadmap. In this research, we consider how to find a local path between sub-goals efficiently.

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Mobile robots often have ultrasonic sensors to detect objects and environment. Sensors are arranged around the robot′s bodies or scanned by some actuators. However, they have problems that they obtain only 2-D information or take much time to scan. Then, 3-D ultrasonic sonar system that can acquire 3-D reflect points at one time is proposed. An Electric spark that works as a non-directional point source of ultrasound is utilized to achieve this system.

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It is necessary to design the bilateral control system in the design of force feedback micromanipulator by adjusting the characteristics of the operator it and the object, and to secure the robust stability of a man, a machine, and an object system. In this research, the new software that was able to design the manipulator and the object system by the interactive method was made for trial purposes. Then, the performance of new software was verified. When, for instance, the master′s movement was reduced to the nanometer order, the trial design of the manipulator was tried.

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In this paper, we proposed a new complex process combined ELID grinding and Magnetereological fluid finising(MRF), and applied this process to fabrication of glass lens. The process may smooth the lens surface to 1nm rms, and achieve the specified shape to within λ/20 peak-to valley (p-v)or better.

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This paper describes an MRF method of a Si mirrors, and the fundamental research MRF characteristics. The spherical mirror with a diameter about 17.5mm made of fused Si which ELID (electrolytic in-process dressing)-grinding high form accuracy with #4000 cast iron bonded diamond wheel, and then polished with the MRF method.

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A new internal precise finishing using magnetic machining jig was proposed to finish the internal surface of thick tube (5~30mm in the thickness). Because the magnetic machining jig consists of permanent magnets, it can generate a higher magnetic force than conventional magnetic abrasives, and makes the internal finishing of thick non-ferromagnetic tube possible. In this research, we paid attention to an internal smooth finishing of a tube, which is rough and uneven in inner surface. The results showed that the convex part of the inner surface was completely removed, and the entire internal finishing of a tube was able to be achieved.

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The previous report examined basic principle of square tube inside polishing. However, we make almost no examination on the polishing quality of the inside of square tubes corner. This study clarifies that the abrasives are introduced to the corners in the square tube by adding vibration, and that effective polishing is carried out inside the square tube.

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The absence of conventional abrasives and the use of an environmentally-friendly grinding fluid are desirable for reducing or eliminating the post-finishing cleaning required, and therefore contributes to a more environmentally-conscious process. This paper proposes a magnetic field assisted machining process employing steel balls in both a distilled water and a water-soluble grinding fluid without abrasive. Experiments using steel bearing balls, which are hardened and uniformly spherical with smoothly finished surfaces, produced smooth finished surfaces when used with the water-soluble grinding fluid. This paper presents the process mechanism, a combination of burnishing and a small amount of cutting; and demonstrates the processing characteristics.

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Authors have been developed particle dispersion typed functional fluid using micro manufacturing under AC electric field at low frequency, These fluids show active reciprocated motion between the electrodes under the selected conditions, applied frequency, viscosity of fluid, and voltage, AC field. We expect to be established the new manufacturing methods for micro electro devises and medical instruments. Then we have obtained a new micro fabrication technology using this functional fluid.

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Electrorheological fluid (ER fluid) is one of the functional fluids, which viscosity increases with electric field intensity. Up to now, performance of electrorheological fluid-assisted polishing of WC micro-aspherical molding dies is investigated. In this case, it is hard to keep the gap between micro-tool and workpiece close, as compared with diameter of micro-tool. And the polishing is very difficult because if micro-tool and workpiece contact, polishing tool scratches workpiece. There, polishing tool is coated with resin material, not to be scratched workpiece. In this report, force on abrasive grain is simulated by FEM and polishing test is done by resin coated polishing tool.

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Precise surface preparation techniques to make atomically flat and defect-free SiC surfaces are strongly demanded in the next-generation semiconductor technology. However, effective technique dose not exist particularly for surface smoothing. EEM (Elastic Emission Machining), which is a precise surface preparation technique utilizing chemical reactions between solid surfaces, was applied to solve the problems. In this work, EEM is employed to flattening 4H-SiC (0001) surfaces. Prepared surfaces are observed and characterized by PSI (Phase Shifting Interferometer), AFM (Atomic Force Microscopy) and LEED (Low Energy Electron Diffraction). Obtained images show that the processed surface has atomic-level flatness, and subsurface damages and surface scratches of the pre-processed surface are completely removed.

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For the purpose of machining ultra high frequency quartz resonator, we study making of quartz wafer with uniform thickness by numerically controlled plasma CVM. In this paper, it was examined the relationship between machining characteristics and machining parameters in order to form an optimum shape of the unit removal spot utilizing rotary electrode and pipe electrode. Then, correction of thickness variation of quartz wafer by numerically controlled plasma CVM was carried out by utilizing rotary electrode. Fabricated quartz wafer had small thickness variation, and the defect density of machined surface is very low.

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Argon actinometry technique has been applied for two-dimensional density mapping of both oxygen and fluorine atoms in the CVM plasma. Extreme narrow bandwidth (- 1.5nm FWHM) of interference filter in visible region allowed us to record monochromatic images of the plasma at 739.9nm (F I : 2s₂2p₄(₃P)3s - 2s₂2p₄(₃P)3p), 750.4nm (Ar I : 3s₂3p₅(2P°1/2)4s - 3s₂3p₅(2P°1/2)4p), and 844.6nm (O I : 2s₂2p₃(₄S°)3s - 2s₂2p₃(₄S°). Each pixel count in both fluorine and oxygen emission images are divided by that in argon image to create two dimensional relative density maps with the principle of actinometry.

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Recently, at third-generation synchrotron radiation facilities, by utilizing modern X-ray microscopy with highly brilliant and coherent X-rays, detailed investigations regarding molecular structures, chemical bonding conditions, etc. have been carried out as objects of various interesting samples including biological and medical ones. Nano-focused X-ray beams are necessary to add nanometer-level spatial analytical ability to the microscopy. X-ray focusing at Kirkpatric-Baez setup with two total reflection mirrors is a promising method from the viewpoints of high efficient and energy tunable focusing. Here we report development of ultraprecise mirror optics and realization of a nano-focused hard X-ray beam. Fabricated mirrors having 0.1 nm (RMS) level accuracy in both figure and surface roughness led to ideal diffraction limited focusing at hard X-ray regions. Focal size defined as full width at half maximum in intensity profiles were 36nm × 48nm at an X-ray energy of 15keV.

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Because CYTOP has high transmittance and a high optical transparency from ultraviolet rays to the near-infrared rays, it is expected as an application material of an optical element. In this paper, the ultra precision cutting of the CYTOP with a natural single crystal diamond was studied.

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Many waveguide-devices have been developed and used in optical fiber communication systems. A broadband optical intensity modulator based on a MAch-Zender interferometer waveguide is a key device for high-speed, long haul, large capacity communication. LiNbO3(Lithium Niobate) crystals with its excellent electro-optic properties have been used mainly for fabricating the modulators, and many manufacturing techniques of waveguide in LiNbO3 have been proposed for broadband operation, lower driving voltage, smaller device-size and smaller optical propagation loss. Our purpose of this study is to examine the possibility of ultra precision cutting for fabricating in a brittle crystal LiNbO3 by using a diamond tool and to show the possibility as an optical device.

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The micro TAS(Total Analysis Systems) is paid to attention in chemical and biological fields. This is made from the glass, engraved thin grooves (width in hundreds of μm and depth in tens of μm) on the surface. If the micro reactor is made by machining, it can be efficiently produced and could be low cost. As the glass is hard, the carbide tool wears easily. Therefore, it is necessary to use a diamond tool, that has very sharp cutting edges. When the diamond tool is used, the crack happens easily. Cutting tests were carried out changing the depth of cut and feed rate. As the result, it is found that the depth of cut shall be very small in order to get the ductile mode surface, but the feed rate could not affected.

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Ultra precision single crystal diamond cutting is widely used from before, because it is able to obtain high form accuracy, surface quality, machining efficiency and capability to machine complicated shapes. But, it is generally restricted to soft metals. Especially, it is impossible for diamond tools to cut steels precisely because of excessive tool wear. However, the advantages of single crystal diamond tools considered, it is important to apply diamond cutting to steel and more materials by restraining tool wear. In cutting steels by single crystal diamond tools, diamond diffuses into steel directly or is graphtized under high temperature and pressure conditions. In consequence, diamond tools wear excessively. Therefore, it is supposed from these things that the main factors leading tool wear are cutting temperature and contact time of the diamond tools and steels. So then, The result of attempt to prevent tool wear with intermittent cutting method are reported in this paper.

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In optical electronics system, diffraction grating devices and pickup lens play a very important role. These devices influence total accuracy of optical systems. Recently, new optical devices having multi-function (diffraction or focusing) are being investigated. New optical devices have such a complicated shape as free-formed microgrooves on 3-D surface. In machining the shape, milling with a rotational cutting tool is not available due to the tool interference. Therefore, a non-rotational cutting tool is introduced in the study together with CAM-system for 6-axis control ultraprecision machining. Utilizing the tool and the system enables to create curved microgrooves on sculptured surface.

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In recent years, the demand for 3-D key microparts is clearly growing for the miniaturization and the integration of engineering products. It is vital to develop three dimensional microfabrication technology. The objective of the study is to manufacture microparts with complicated shapes by means of ultraprecision machining. In the study, a 3-D CAD/CAM system for the multi-axis control machining is developed in order to manufacture a micro axial-flow pump, which is a target shape.

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In this study, an efficient manufacturing method for microparts is examined. This study also deals with a microcutting process and an assembly process. In the microcutting process, we investigate the tool pass in which the cutting force does not act on microrods as products during the cutting operation. A microdrilling technique is also examined, which can prevent the bending of microrods during the drilling process. As a result, it is clarified that the microcylinder parts including micro-piston rod and micro-cylinder tube are successfully fabricated, and they are assembled each other.

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This paper describes development of optical element ultraprecision cutting by 6-axis ultraprecision machine tools “Super Meister”. This machine can use different grinding wheels or cutting tools with attachments. Using this machine a mold of X-ray reflective optic has been developed.

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Effects of atmosphere have been investigated on fracture strength in bending test and ductile-to-brittle transition in scratch test. Kaneeda et al noted that mechanical properties of brittle materials can be controlled by the atmosphere. Four-point bending test and scratch test have been conducted using BK7 plates whose surfaces were coated by n-Stearyltrimethylammonium Chloride (amine) as an applied material. The experimental results indicated that the fracture strength increased and the length of ductile area expanded by applying amine on the surface of glass. These results suggested that applying amine on the precut surface could act effectively in ductile regime machining of BK7 plates.

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Recently, aspherical optical parts are installed in various optical instruments such as digital camera. As pixel number of digital image sensors increases, both high form accuracy and fine surface roughness are required. However, distortion in an optical image occurs even if the aspherical optical parts, which has high form accuracy and fine surface roughness. The distortion of the optical image is caused by the waviness of small amplitude, which is generated in the cutting process. The small waviness is named nano-topography. In this study, the relationship between cutting conditions and the distribution of the nano-topography is investigated.

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This paper presents a nanomachining instrument with nanometrology function for precision nanofabrication of large area free-form surfaces. The diamond tool for diamond turning is mounted on one end of PZT for nanomachining of micro-structures through employing the fast-tool-servo technique. The same instrument can also be used for nanometrology of the machined surface through utilizing the output of the force sensor mounted on the other end of the PZT. During the scanning to measure the surface profile, the diamond tool is servo controlled by the PZT so that the tool tip is kept contact with the surface with a constant contact force. The displacement of the PZT, which corresponds to the profile height of the machined surface, can thus be obtained from the capacitance sensor inside the PZT.

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Micro-meso mechanical manufacturing (M4) technology has recently attracted attentions as an alternative micromachining solution because of its potentials of processing variety in materials into 3 dimensional forms. Using a micro lathe, which is installable and operational in a SEM (scanning electron microscope), we control the position of XY stage of the micro lathe with visual feedback from CCD camera. We investigate the movement mechanism of XY-stage, and the recognition accuracy of image processing.

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Shot peening is a working process to improve mechanical properties such as fatigue strength, stress corrosion cracking and delayed fracture. Although such peening effects induced by compressive residual stress and work hardening, their relations are not clarified quantitatively. In order to clarify peening effect on fatigue strength shot peening were performed for a medium carbon steel using steel shot by a centrifugal peening machine. As the results the following results are obtained; (1)Critical thickness defined by the ratio of the thickness of work material to the depth of work hardened layer is about 5 on the medium carbon steel. (2)The maximum peening effect will be obtained that the thickness of work material is thinner than the critical thickness for each peening condition. (3)Recovery of surface layer are happens during fatigue test accordingly to the dent size.

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In order to machine a metal plate, metal jet machining is used instead of water jet machining. In this report, the observed form of metal jet and the measured jet force are described.

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