In this study, drilling of titanium alloy was carried out with ultrasonic vibrating carbide drill. As a result, the ultrasonic vibration drilling was performed more than 400 holes under the chip load of 20 μm/rev. As compared with the conventional drilling, the ultrasonic vibration drilling suppressed the deviation of holes diameter and burr formation. Additionally, the device was proposed to visualize process of ultrasonic vibration drilling of analyzing internal stress field on workpiece while processing. The configuration of device is combined with the high-speed camera and photoelastic method. The visualization device observed that the internal stress field varied alternatively which was synchronizing with ultrasonic vibration.

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Design of the restrictors of a hydrostatic thrust bearing maximizing bearing stiffness is considered in the paper. In particular, the paper focuses on a design of restrictors used in the opposed pad hydrostatic thrust bearings sustaining vertical loads. In such cases the table supported by the bearing moves from its neutral position. Numerical analysis indicates that an achievable highest stiffness for various bearing positions can be represented by an envelope curve derived. Using proposed design procedure, the bearing stiffness of our water hydrostatic thrust bearing becomes 1.5 times of that of the previous design at given operational condition.

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This study aims to extend patterned self-assembly of fine particles on a flat substrate to that on curved surface such as cylinder. Firstly, wettability pattern was fabricated on a cylinder using contact printing, and then the cylinder was dipped in and drawn up from the suspension that contained nanometer particles. The proper conditions were made clear from the standpoints of the contact print, wettability pattern design and the dip-coating characteristics respectively.

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Molding is an effective and efficient approach for producing highly functional optical elements with complex shapes. However, edge sharpness is a serious problem with molded microstructures. Ultrasonic assistance can induce heat generation and reduce friction during the molding process, and therefore, an ultrasonic-assisted molding (UAM) device was developed to improve shape transferability and demolding performance. First, basic experiments showed that UAM induced a maximum temperature increase of 3.2℃ for a polycarbonate substrate with a starting temperature of 170℃, and the stick-slip phenomenon was not observed with ultrasonic vibration. Second, UAM and conventional molding simulation models were constructed to compare the transferability of a microgroove; ultrasonic superimposed press movement demonstrated the highest transferability. Finally, microgratings were fabricated using UAM and conventional molding, and the UAM micrograting had better transferability with a 30-s molding time. Therefore, UAM may be an effective process for reducing molding time.

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The demands for manufacturing thin silicon wafers have increased following the advancements in technology. To increase product efficiency and accuracy of semiconductors, a new method for holding the silicon wafer is required. An electro-adhesive gel (EAG) is a new material developed as a functional material applied to hold the devices. The EAG can change its surface adhesion properties depending on the applied electric field. Based on the structure of the EAG, a new function that can change its thermal conductivity is developed. The new function is expected to enable quicker cooling of the wafer, leading to a more efficient manufacturing process. From the experiment the EAG can change its thermal conductivity for about 20%.

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A common problem in handling paper by conventional rubber-layered rollers is simultaneous handling of two paper sheets, so-called double-feed. This study describes the basic performance of an alternative material, electro-adhesive rubber (EAR). Instead of inducing friction between the paper and a rubber-layered roller by a vertical force, EAR handles paper with adhesion. In this study, we determined the adhesive fixing force between EAR and a paper sheet. The maximum pressure on ordinary copy paper was approximately 1.8 kPa, or 110 N on an A4 sheet, demonstrating the suitability of EAR as a rubber-layered roller substitute.

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Grinding machines that employ a high-speed reciprocating worktable or wheel head are known as high-speed reciprocation grinding. The high-speed reciprocation grinding is developed to achieve high-efficiency grinding. It is said that the high-speed reciprocation grinding has many advantages such as low grinding heat, small grinding force. However, there are few investigations on the characteristics of high-speed reciprocation grinding. In this study, relationships between the grinding force of high-speed reciprocation grinding and grinding conditions are investigated.

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The standard of test method for 5-axis machining center is now under discussion by ISO. In its draft standard, the use of a measurement device with three displacement sensor is described. Then, design and prototyping of the device that was able to take the setting method freely were done. Using the newly-designed device, three comparisons of the setting method were performed. One is of the conventional setting method developed in Europe, another is the method that sensors are parallel to the machine axes, the other is that the device is attached on the spindle.

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NC programming for multi-tasking machine tools requires much time and labor. The study proposes the rationalization of the process planning by extracting the machining feature in consideration with turning and milling from targeted complex shapes to be machined and by both selecting the suitable machining method and arranging the machining order automatically. As a result, it is expected to reduce the preparatory time on CAM system, using output data from the proposed system. Applying the system to several product shapes containing both turning feature and milling feature, it is confirmed that NC data can be obtained for each shape without any problem.

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The five-axis CNC (computer numerical control) machines are highly flexible compared to those with three-axis and this makes them becoming popular in modern industries. In this paper, we propose a novel sliding mode contouring controller with a nonlinear sliding surface for five-axis machining tasks. The controller aims to reduce the tool tip and tool orientation contour errors. In addition, we design a disturbance observer to compensate for the effect of modeling error and external disturbance. The proposed controller with the disturbance observer results in a good performance compared with the conventional controller in terms of tool tip and tool orientation contour errors.

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This research aims to develop an automatic process planning system based on machining feature recognition in complex machining to achieve high accuracy and a short processing time. Disassembly of delta volume is an important aspect of machining features generation. Therefore, previous studies on disassembly methods are briefly discussed. Solidworks API was used in the designed system for automatic disassembly of the delta volume into simple machining features, feature recognition, tool-path generation and calculation of processing time. In this research, a new approach to machining feature recognition has been developed based on a dimension table. This system is able to evaluate all possible machining solutions and sequences, and identify the machining sequence which has the shortest processing time.

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A new method based on turning has been developed that can machine a non-axisymmetric workpiece by using two translation axes that are synchronized to the rotation of the turning spindle. However, at present, since there are no CAM applications that can support this new machining method, tool paths have to be obtained using a commercial 3D CAD program and geometric calculations have to be made for each workpiece. Therefore, this paper deals with a versatile tool path generation method that can replace the conventional method. An original CAM application for this machining method is proposed, and its effectiveness is confirmed.

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Friction is a primary disturbance in mechanical motion control of high precision machines. Because the friction causes undesired effects such as steady state and tracking motion errors of industrial machines, control systems should be designed to compensate for frictional effects. In this paper, we propose a simple yet really efficient method for estimating the friction property in biaxial feed drive systems. Our method employs the conventional circular contouring control results in estimating the friction property for contouring controller design. The effectiveness of the proposed method is demonstrated by experimental results for different contour curves in different motion speeds.

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The objective of the present research is to establish mathematical models representing kinematic motion deviations of 5-Axis machining centers. A systematic procedure is proposed to estimate kinematic motion deviations of linear tables and rotary tables based on geometric deviations of guide-ways. A model is developed by combining both the models of the linear table and the rotary table and applied to the analysis of the 5-axis machining centers.

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In order to comprehensively solve dynamic production planning problems, useless combinations that do not satisfy constraints should be removed in advance. This paper describes a representation of the solution candidates that are valid combinations by using the Zero-suppressed Binary Decision Diagram (ZDD). Experimental results applied to a sample planning problem demonstrate that the ZDD is efficiently used to represent only feasible combinations of alternatives adapting to dynamic changes.

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The objective of this study is to propose a work instruction system for workers to understand the assembly processes quickly and reduce their assembly times of products without repeating same assembly processes. According to the learning curve of workers, it is important that the assembly time should be reduced from the first time the workers assemble the products in order to increase the productivity of cellular manufacturing systems. This study firstly analyzes the learning processes of workers and develops a work instruction system for assembly cells.

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This paper deals with job shop scheduling problems in which overtime can be adjustable to meet due dates. The primal objective of scheduling is to meet due dates and the secondary one is to minimize overtime. For this purpose, we propose the scheduling method using the mixture of genetic algorithm and priority rule. Numerical experiments show that the proposed method can generate optimal or sub-optimal solutions when the scale of problem is small or time resolution is low. When the size of the problems is large and time resolution is high, although it becomes difficult to obtain optimal solutions, the performance of the proposed method is much better than other methods.

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Ultra-precision cutting experiments were carried out using a single crystal diamond (SCD) tool and a poly crystal diamond (PCD) tool for the finish cutting of the tungsten carbide, in order to investigate the influence of the WC particle size and the cutting conditions on the finished surface quality, As a result, although the ploughed dimples remain on the cut surface by PCD tool, the good surface without the defects was obtained in the case of using PCD tool. Furthermore, with a decrease in WC particle size, the surface quality was improved and the roughness reached to 0.01μm (Ra).

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Improvements in the productivity of a multi-tasking machine based on an NC lathe have been achieved by the following, 1) improvement in the performance of the machine tool, and faster response of mechanical parts, including shortening the machining time depending on the cutting conditions, 2) reduction in the total machining time by streamlining the process design and the NC program for complicated workpieces, and 3) simplification of the dedicated machining process using a multitasking machine tool. In this study, we investigate improvements to the process design method for multi-tasking machines by referring to a skilled programmer's NC programs.

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This paper proposes a non-contact and on-machine measurement method for evaluating tool edge geometry. A focused laser beam having a diameter of several micrometres traces over the tool edge, while the both of signals are monitored. By utilizing a light intensity of the laser beam passed around the tool, the perpendicular distance between the optical axis and the tool edge is obtained. Measurements have been carried out with a scanning speed of 16.7 μm/s on the ultra-precision machine lathe. The measurement resolution of 30 nm of the method can be developed to greater than the diffraction limit.

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A method is proposed for self-evaluation of edge contours of single point diamond tools on a force-controlled fast tool servo equipped on a precision lathe. A sharp point referred as reference point is generated by using the diamond tool to cut two round-shaped grooves with overlapping boundary. The diamond tool is then scanned by the reference point through servo control of the contact force, in which the edge contour is obtained by reversing the scanning trace of the tool. Experiments of evaluations of tool edge contour and out-of-roundness are carried out to demonstrate the feasibility of the proposed method.

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This study discusses about the effect of the deviation of the vertex of the "triangle" cutting edge shape on the brittle cracking in the glass cutting. In cutting tests, the shaper process is performed on the soda lime glass by a single crystal diamond tool. The diamond tool has the artificial "triangle" wave edge shape which re-dressed by FIB machine tool. In this study, vertexes of the edge shape are deviated to the specific direction to evaluate effects of the deviation of the vertex on the brittle cracking. After the shaper process, the propagation of the brittle cracking under the machined surface is observed by the FIB and scanning ion microscope (SIM). By the SIM observation, it is clear that the direction of the brittle cracking was changed by the length of the deviation of the edge shape vertex.

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The Great East Japan Earthquake, which happened on March 11, 2011, made us aware once again that we had forgotten that we were just one species within the great cycle of nature on earth, that we were allowed to survive only because of nature, and that the idea that we were somehow able to conquer the nature was simply an illusion. Now, more than ever, is the time we must confront face-to-face the change from the underground resources type of civilization to one with a new way of life and technology that embraces a sense of nature. To do so, we must learn from nature that possesses the only sustainable society on earth and create technology which embraces such a view of nature. We call technology, which cleverly revives nature's greatness, Nature Technology, and we have completed fundamental consideration of the micro-wind generator using mechanism of the dragonfly's wings, water free bath learning from bubbles, stain free surface learning from snail shell, electricity free air-conditioner and others. We must now, in the midst of severe environmental restrictions, begin the great challenge of suspending and cutting back our escalating human activity, while living in a spiritually enriching way. How can we live in a spiritually fulfilling way on one planet? In order to find the form that this new way of life will take, we certainly need to adopt a backcasting point of view which starts with the prerequisite that we live on only one plane

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