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We have developed an ultra-precision 5-axis cutting machine and achieved form accuracy 10nmPV and surface roughness 1nmPV. In this publication, we introduce the constitution of the machine, characteristic evaluation results such as the static stiffness, and the machining results of plane, sphere, and grating. In addition, we introduce a linear stage technology with built-in vacuum optical path for position accuracy improvement and an air bearing flow adjustment technology for rotary accuracy improvement as main key technology.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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In the compression molding of O-rings using fluoro-elastomer, string-like preform is set by hand inside the mold cavity which is maintained at a high temperature. For this reason, the operator has to have the necessary experience and skills, or deterioration of mechanical properties and external defects of the molded products will occur, resulting in major problems at the production site. In this study, we focused on clarifying the problems in this fluoro-elastomer compression molding process, and attempted to design and fabricate induction heating and cooling mold that do not require experience nor skills from operators. Through molding experiments, we confirmed the usefulness of the mold.

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I will study on developing actual automatic control robots in a uneven ground using self-localization by sensors and communication with other robots and base stations. In an actual machine the value of GPS and sensor are not precise, so I use a filter improving the accuracy of the sensor value and employ them in robot system. However I think it is no enough to use only GPS and sensor data. So I use communication with neighboring in other robots and base stations and estimate the robot place to improve the precision of self-localization.

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[in Japanese]

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It is aimed to make clear the most effective training logics to let beginners to acquire milling machine technology. In the 2nd report, worker's autonomic and central nervous system activities were measured during milling machine operation to compare these characteristics of expert to experienced. LF/HF, an index of sympathetic nervous activity, was obtained with the worker's heart rate variability to evaluate the autonomic nervous system. Hemoencephalography (HEG) sensor based on near-infrared spectroscopy (NIRS) was used to estimate brain activity from the blood flow of prefrontal cortex. As a result, Expert-experienced differences in LF/HF suggest that the experienced gets more stress than the expert. Though apparent difference in the brain activity was not observed, the blood flow of prefrontal cortex in the expert during the operation may increase more than that in the experienced.

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Development of high efficient and high accuracy slice processing technology is required for realizing the high quality and low cost large SiC wafer. Our target of high speed slicing is slicing a 6 inch SiC single crystal ingot in about 9 hours. This slicing speed is about 10 times higher than the loose abrasive slurry sawing. The slicing speed and the slicing accuracy are in the relationship of trade-off. Therefore, in this research, we have realized the high wire speed of a multi wire saw and we have studied the high speed slicing technique of SiC single crystal ingot aiming at reduction of sliced wafers SORI. As a result, we found out that the high speed slicing is possible and the warp of sliced wafers become small, as wire speed becomes high. We confirmed to improve the relation of a trade-off between the slicing speed and the SORI of the sliced wafer by high wire speed. We could get wafers of about 25 μm SORI in slicing a 4 inch SiC single crystal ingot in about 4 hours (which slices a 6 inch SiC single crystal ingot in about 9 hours by area conversion).

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The performance of wire-sawing in vacuum has been investigated for future lunar and planetary explorations. Nickel fixing abrasives adhered on a rock specimen in vacuum and the rock was hardly cut. In this report, the causes of the adhesion were estimated by friction tests. The nickel surface became oxide in air and more brittle than pure nickel. Consequently, nickel was removed in air. On the other hand, nickel was not oxidized in vacuum and was still tough and soft after rubbing. In addition, debris adhered on the machined area by electrostatics. Consequently, the abrasives slipped on the nickel and machining did not progress.

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The R-test is an instrument to measure three-dimensional displacement of a precision sphere, attached to a machine spindle, relative to a work table by using three displacement sensors. Its application to error calibration for five-axis machine tools has been studied. This paper presents a software to analyze measured R-test trajectories for error diagnosis and numerical compensation of rotary axes location errors and error motions. Experimental demonstration of its application to a five-axis machine tool with ne rotary axis in spindle side and one rotary axis in workpiece side is presented.

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Square and radius end mills have some advantages such as the long cutting edge and the large amounts of removal volume compared with ball end mill. Therefore, the end mills are mainly used for rough cutting. In the previous researches, the calculation method of tool center points for five-axis controlled machining by use of square and radius end mills, and the limitation of tool attitude change in tool feed direction had been proposed. However, the generated tool path for rough cutting was insufficient as the preliminary step of finishing cutting, since the amount of cutting remains was too large, and the height of cutting remains was non-uniformly distributed. In this report, we developed the tool path generation method for the five-axis controlled machining using the side of square and radius end mills while selecting suitable cutting points and tool attitudes so as to keep the cutting remain minimum. As the result, the usefulness of devised method was confirmed by some machining simulations.

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A study of the electrochemical growing process of polymeric micro/nanowires was carried out on the purpose of brain growth emulation using Machine Learning Algorithm in the combination with acceleration circuits. Polyyrrole (PPy) and Poly 3, 4-Ethylenedioxythiophene (PEDOT) conductive polymer wires have dendritically grown inside electrolyte solution placing between the designated microelectrodes, which were prefabricated by lithography, under an applying of directed current (DC) square wave voltage signal. This study will demonstrate the growing process of PPy and PEDOT wires and point out its unique characteristic potentiality in application of machine learning and artificial neural networks, the core research of dynamic brain growth emulation.

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In the field of biomolecular science, chirality is one of the most important properties. All of the biological molecules are alternative enantiomers, that is, has chirality. In this research, we evaluated various properties of chiral molecular nano-assembly investigated by the scanning tunneling microscopy (SAM)-based technique.

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A novel plasmonic point light source could be created with excitation, propagation, and focusing of surface plasmon polaritons (SPPs) at tip of circular truncated conical shaped optical fiber covered by metal-insulator-metal (MIM) structure. A twin hole opening in the MIM structure might be able to act as an efficient waveguide for the SPPs. The well-designed asymmetric MIM structure could operate as a reflective notch filter at visible region. The filtered monochromatic light is converted into SPPs propagating along interfaces in the MIM structure. Our objective is a realization of such a novel probe for scanning near-field microscopes. This paper describes a basic numerical simulation of electromagnetic field around a tip of the plasmonic probe. The simulation is based on finite element method, and the basic results both three-dimensional near-field analysis and two-dimensional modal analysis are reported. The modal analysis of the twin hole indicated that spatial configuration of the two holes will make or break the efficient waveguide for the SPPs, and each thickness of the MIM structure determines the wavelength of SPPs. The whole knowledges will support an optimal structural design for the plasmonic probe.

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Sapphire has high hardness and chemical stability. Therefore, it is difficult to machine the sapphire. The sapphire is reacted by steel during friction. Sapphire was machined using this reaction in our method. Cylindrical carbon steel was chosen as the steel materials. The wear of sapphire was regarded as the removal of the sapphire. The machined depth of the sapphire was increased with the machining time. The Machined depth under the water atmosphere became less than that under the air. The smooth surface was obtained under the water atmosphere. When the chips were removed at the machined portion, removed volume was decreased. The chips have any roles for the machining.

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