This study was conducted for developing the testing methods by means of simultaneous five-axis motion in five-axis controlled machining centers with a double pivot spindle head. Two of the three kinds of simultaneous five-axis motions were introduced for the identification of the deviations inherent to the five axis machining centers. In the first step, the ball bar was set parallel to the A-axis of the spindle head and in the second step the distance between the ball of the spindle side and the center of the A-axis was extended and then the measurement was repeated. In the third step, the ball bar was set tangential to the A-axis rotation. The observation equations and the geometric analysis were applied to the identification. The ten deviations inherent to the machining centers were accurately identified through these three steps.

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A lot of techniques for generating the tool path of 5-axis controlled machining that consider the avoidance of tool interference etc. are already proposed. Main commercial CAM software enable to calculate the tool path that is enough for practical use in the point that there is no tool interference. However, the current technique had the problem of outputting the tool path that was not available for the machine tool because the movable range of driving axes of the machine tool was not considered. In this report, the technique for calculating the tool path considering not only the tool interference avoidance but also the movable limit of an inclination axis of 5-axis controlled machine tool is proposed. Finally, the effectiveness of the technique is shown by the machining of the complicated shape that requires the great inclination of the table.

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Nowadays, 3-axis control machining is generally performed in roughing process. However, 3-axis control machining is not efficient in case of roughing complicated shape, i.e. parts with overhanging shape, because it requires resetting the workpiece. To solve this problem, this study deals with roughing by 3+2-axis control machining. 3+2-axis control machining is performed by 3 translational axes after tilting a tool axis vector by 2 rotational axes. For 3+2-axis control machining, the determination of tool axis vectors and tool diameters affects the rough machining time especially. The study proposes a method of determining optimal tool axis vectors and selecting tool diameters for efficient roughing.

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This paper describes the measuring methods for positioning accuracy of tilting axis in five-axis controlled machining centers with a tilting rotary table. The top surface of the tilting rotary table is generally in higher position than the tilting axis. In this case, there is no measuring method except a manually operated clinometer. Thus, a clinometer consisting of a precision rotary encoder and a precision bubble level was firstly developed. In the method, operators have to read visually the scale of the level and the reading accuracy is dependent on their ability. Instead of the bubble level, an electronic inclinometer with high resolution was also developed. In addition, a ball-bar equipment was applied to the measurement of the angular positioning accuracy of a tilting rotary table. Since the ball bar equipment can measure the angular displacement continuously, the pitch error compensation will be accomplished precisely.

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A polar coordinate desktop machine tool (P-DMT) with 2 rotary axes and 1 linear axis which is suitable for measurement or machining of free form surface is developed. This paper describes its component, form generation function and method to identify assembly errors in it. Measurement accuracy improves when form generation theory is applied to compensate these errors.

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NURBS (Non Uniform Rational B-Spline) is well known to express free-form curves and surfaces in current CAD systems. In addition, controllers to accept NURBS format are available together with CAM systems to generate NURBS interpolation NC data. NURBS interpolation NC data have more advantages than conventional ones, for example, no error in comparison with approximating curved lines by small line segments, small amounts of NC data and so on. In the present circumstances, there are some main processors to generate CL data using NURBS interpolation for simultaneous 5-axis control. However, there are few post processor to transform CL data into NC data. Conventional post processors generate a large amount of NC data, while decreasing them at the expense of interpolation accuracy. Therefore, the study deals with a post processor which can create practical 5-axis NURBS interpolated NC data, considering the interpolation accuracy.

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In these years, many of production facilities have been transferred to overseas. It is expected to create and develop an original manufacturing technology in Japan, which produces high value-added products. Processing by mold has brought the solution for mass-production of micro and precision parts replying to cost saving demand. Micro-machining technology is highlighted for the machining of precision mold and applicable Micro End Mill is required. To meet this requirement, NS Tool has successfully developed the Micro End Mill and joined it in the standard product. It is smaller than a human hair in diameter. In this report, we introduce features of the Micro End Mill, its work samples and how we manufacture this product.

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Fabrication of one tooth micro ball endmill with sharp cutting edge without chips was conducted using various sintered materials as a tool material. Electroplated diamond tools and a resin-bonded diamond wheel #32000 mesh size were employed for the roughing and finishing of the tool fabrication, respectively. As to the roughing of a PCD tool, EDM using electroplated diamond tool as a cathode was conducted. It was verified through the experiment that sharp cutting edge without chips could be fabricated to the tool materials under 20GPa Hv in hardness by using a resin-bonded diamond wheel for the finishing. As to the cBN and PCD, cutting edge without chips could not be obtained when using electroplated diamond tool was adapted for the finishing.

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In the field of the ultraprecision cutting, die machining can be processed mirror finished surface with lathe. But the processing system has the fault that the created shape is limited to an axisymmetric side because of the gyration with the lathe main axis. In this study, a new processing method which can achieve to create the asymmetric shape are proposed. Then, effectivity of the proposed method is confirmed.

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Glass cutting is discussed to improve the machining rate with the roughing process. Glass can be machined in a large axial depth of cut more than 0.1mm in the roughing process. The brittle damage occurs in the subsurface less than 10μm deep. The brittle damage, then, can be removed in the finishing process. A machine tool is developed to manufacture micro-scale parts in cutting. The machine tool has 5 axes driven by stepping motors with high resolution. The machine tool has a table controlled by the linear motions of X- and Y-axis and the rotational motion of A- and C-axis ; and a spindle with the cutting tool controlled by Z-axis. The machining processes can be controlled by a personal computer. Some cutting tests are performed to verify the design and the efficiency in micro machining on the developed machine tool.

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This paper discusses 3D micro machining technology which can realize the micro channel with variable depth and width on glass plates. Etching process can not make 3D shape of groove. Therefore we carried out the basic study on the 3D cutting of glass with micro ball end mill. Concretely, property of the machined 3D channel was evaluated experimentally. Cutting force in descent direction is heavier than rising direction. Compared with DLC and diamond coating tool after cutting, diamond coating tool is better than DLC that in wear of tool. Moreover in observation of the 3D machined surface, better surface can be obtained when tilt angle of spindle is 45°

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Unlike the traditional fixed abrasive process, the CMG process produces no damaged layer by introduction of chemical reaction with the work-pieces. It can create the defect-free surface with the grinding process only. The research has conducted the primary experiments on optical glasses, analyzed the results to determine the optimum parameters.

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Micro-fluid devices and optical devices need minute patterns on their surfaces. Recently, the improvement in optical characteristics and chemical-resistance is demanded. Therefore, it is important to make such devices with glass. Minute process of glass is done by photolithography mainly now. But its process is complex and it costs much. Imprint technology has advantages in such sense. But, glass imprint is difficult, because forming temperature is high. In this research, glass imprint with CVD diamond mold is proposed. CVD diamond has advantages in high temperature. FIB process of CVD diamond mold is proposed and the conditions of process are clarified. Imprint of glass is tried by using CVD diamond mold.

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In this paper, the surface and subsurface of silicon wafers ground by different types of diamond wheels have been studied. It is found from the top that the subsurface of wafer consists of amorphous Si, followed by strained crystal with a large compressive residue stress, and then the bulk material in single crystal. In a severe condition which causes grinding burn, part of amorphous Si is re-crystallized to form a poly-crystal Si, and part of amorphous Si possibly reacts with oxygen to form SiO_2 Authors have proposed a new chemo-mechanical grinding (CMG) process for effective stress relief and damaged-layer removal.

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Computer-aided design (CAD) systems have been developed for modeling the desired 3D forms of products and they are useful for improving efficiency of product detail design. However, it is often difficult to use CAD systems for aesthetic design because aesthetic design is creative activity and strongly depends on creativity of designers. If designs can be controlled by using indexes, they make CAD systems valid for aesthetic design processes. This paper proposes three shape evaluation indexes to quantitatively evaluate shape image of curves.

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This paper deals with an interface system which is effective in the conceptual phase of the design process. The interface system recognizes primitives: cylinders, cones, spheres, and cuboids from sketches of functional components drawn by a designer and constructs 3-D models. The algorithm of the system is so built as not to obstruct thinking design of the designer. The results show that the recognition of the primitives has been done correctly, and the implementation of the system in a 3-D Computer-Aided Design system can help the designers to shorten the time of designing.

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The purpose of the present research is to develop an integrated process planning and scheduling system, which is applicable to the holonic manufacturing systems (HMS). A basic architecture and systematic methods are proposed to determine suitable sequences of manufacturing equipment needed to manufacture the products and suitable production schedules for the manufacturing equipment in the HMS. Procedures are developed to carry out both the process planning and scheduling, by applying the genetic algorithm and dispatching rules.

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One of the most important performance indices of the machine tools is the machining accuracy in the multi-axis machining process. Therefore, it is required to establish systematic analysis and design methods for the multi-axis machine tools, from the viewpoint of the machining accuracy of the complicated products. The objective of the research is to establish mathematical models representing the shape generation motion deviations of machine tools, on the basis of the geometric deviations of the relative motion between a pair of connecting units with respect to the priority of the geometric features. A case study on the kinematic motion deviations of the three-axis machining centre is carried out with the proposed method.

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In machining process using multi-axes CNC machine tools, the kinematic model and the shape model for the machine tools are necessary to generate NC data and to simulate the motion of machine tools. However, in such case, both models are not integrated into one machine tools model, and some problems have arisen. For example, some NC data contain interference between a cutting tool and the elements of the machine tools in NC generation process, and the relations between kinematic model and geometric model of machine tools should be created whenever the NC simulations are performed. In this study, an integrated model to connect kinematic model with shape model for machine tools based on STEP (ISO 10303) is proposed. Also, to verify the proposed model has enough information for machining, the integrated model for 5-axis machine tools is generated, the motion data are generated and the motion of machine tools is simulated by using this generated model.

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"Computer-aided flexible process planning system" was developed due to the function of automated process and operation planning by a machine tool for autonomous distributed manufacturing system to realize mass customized production. In this system, several sets of machining features are detected automatically from the total removal volume (TRV) which is the difference between 3D CAD models of the workpiece and the product. Then, several process plans are proposed based on the sets of machining features. Design information, such as surface roughness or dimensional tolerance, is useful to select suitable process plans. Moreover, these process plans are evaluated by their machining time and production cost to select the best process plan.

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In order to prepare a good NC program, which can avoid machining troubles and achieve high machining productivity and accuracy, a sophisticated machining process simulation is required to predict whole machining operation. In this study, the Voxel model is applied to predict change of geometrical machining shape during machining operation. Additionally, the cutting force simulator is integrated to the geometrical machining shape simulator to evaluate machining process before actual machining operation. Cutting parameters such as depths of cut and stepover can be detected by the geometrical machining shape simulation, and then cutting forces can be predicted by the cutting force simulation.

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Recently, a demand for precision machining of dies and molds with complex shapes has been increasing. Even CNC machine tools are utilized widely for machining, still machining error compensation is required to meet the requirement of machining accuracy. However, the machining error compensation is a skilful operation which takes huge amount of time and cost. This paper deals with a way of the machining error compensation. The 3D surface data of the machined part is modified according to the machining error measured by CMM (Coordinate Measuring Machine). A newly NC program is generated from the modified 3D surface data for the machining error compensation.

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A demand for the mold of micro-lens is on the increase. As a system for the machining of micro-lens mold, a desk-top machine tool is being expected. But, when the grinding wheel with the small diameter is used, the ELID grinding method has a problem about the installation setting place of the negative electrode along the wheel. In this research, we developed a system to electrolyze the small type ELID grinding wheel. This system was realized ELID grinding processing without using the negative electrode along the wheel, for the purpose of machining of micro lens mold. That result succeeded in the development of the SLID grinding system which uses nozzle type electrodes (new electrode less ELID grinding method). Then, the processing using this system could get the mirror surface of Ra 12nm without electric discharge scar. There was a small abrasion of SLID grinding wheel and abundant volume of material removed.

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The reaction layer at the surface of processed work has conventionally been perceived negatively as a sub-surface damage layer. However, in a recent study, the authors clarified that the ultra precise mirror surface finishing method could modify the work surface during grinding (removal process). This method is expected to produce various effects such as inducing an oxidization reaction on an active new surface immediately after processing, to thereby coat the surface with an anti-corrosion film, advantageously transforming the components of the tool or grinding fluid to the surface. This paper discusses applications of these latest techniques.

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in order to create high bone compatibility surface, a new ELID grinding system, in which a direct current of extremely short pulses are applied to the sample being ground was developed. After the titanium metal was subjected to a new ELID grinding, thin film Energy Dispersive X-ray Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM) results showed the titanium metal surfaces were covered by porous titania. In simulated body fluid (SBF), the titanium modified by a new ELID grinding system could induce apatite formation on its surface. Above results suggest that this newly developed ELID grinding system can facilitate rapid bone formation around the implant, reducing therewith the patient's recovery time after surgery.

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We have developed and have used "ELID honing method", for finishing of automobiles' cylinder bores' inner surface, used the effects of "ELID grinding". Using this process, reduced the processing time per cylinder from 40% to 50%, for finishing the bore portion of a cylinder, and improved the accuracy and stabilization of the bore face properties.

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Ultraprecision optical components require ultra-fine smooth surface quality of sub-nanometer or sub-angstrom in Ra. To achieve these requirements, ultaprecision on-machine measuring system in very important, by which the profile measurement and evaluation is conducted on the machine, the form accuracy by the compensating machining when the form accuracy in not enough. So, on-machine profile measuring system with contact-type probe has been developed.

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Optical components with micro groove structures like diffraction gratings, light guide plates or holographic optical elements require extremery high form accuracy and ultra-fine smooth surface quality of sub-nanometer or sub-angstrom in Ra. To achieve these requirements, ultaprecision on-machine measurement system in very important, by which the profile measurement and evaluation is conducted on the machine, the form accuracy by the compensating machining when the form accuracy in not enough. So, on-machine profile measuring system with non-contact laser type probe has been developed.

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Silicon carbide (SiC) is the most advantageous as the material of various telescope mirrors, because SiC has high stiffness, high thermal conductivity, low thermal expansion and low density. Therefore, we developed the ultra lightweight mirror by ELID grinding method which can obtain the surfaces of very hard materials efficiently. If a mirror becomes large, shape of the mirror becomes complicated, and thickness of the mirror surface and a lib part becomes thin for lightweight. Accordingly, it is thought that surface roughness of the mirror deteriorates by influence of vibration. And then, to improve the precision of the surface roughness, we did the ELID grinding by cross cut that the axis of rotation and a progress direction of a grinding wheel were vertical.

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In this paper, we proposed a complex finishing process of MRF and ELID grinding and applied this method to nano-precision finishing for glass lens. ELID grinding, as pre-finishing, was employed to obtain high form accuracy and good surface quality in high efficiency. And then, MRF, as the final finishing, was used for improve furthermore surface quality and figure accuracy. Several sets of finishing experiments for sphere glass lens have been performed to verify obtainable surface figure precision and surface roughness by use of this new synergistic process.

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ERG (Electro rheological gel) is a functional material whose frictional property changes according to the applied electric field intensity. In this study, developed ERG is applied to fixture device. It is easy to fix and detach a workpiece due to applying and releasing a voltage to ERG fixture. Moreover, ERG fixture can fix a workpiece without external force, therefore workpiece does not bend. The prototype of ERG fixture is manufactured and its characteristic is evaluated by glass cutting test. The result shows that ERG fixture has enough friction force to fix the glass workpiece and the vibration of workpiece was reduced by higher applied voltage. In addition, it is clarified that ERG fixture with the special patterned one-sided electrode, whose electrode width is changed, is effective for micro alignment.

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Electro-Rheological Gel (ERG) is one of functional materials which change their frictional property by applying electric field. A flat plate placed on the ERG sheet clings to the gel by applying an electric field and ERG produces the shear force to the upper plate. Applying ERG to machine parts has been expected because ERG can change the shear force easily by applying electric field. The one-sided pattern of electrodes, which has been developed for Electro-Rheological Fluid (ERF) devices, is a very useful idea to free sliding or rotating parts from wiring arrangements. In this study, the optimum design of one-sided pattern electrodes for ERG is carried out.

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In this thesis, the result of the research that looked for the best shape of the circulation route of the end cap to reduce driving torque of a linear guide was put. The research that had been done this time experimented on the change when the curvature radius of the circulation route was changed. The result is brought together as follows. (1) It would be better to be composed only of the curve without mixing the straight line. (2) The frictional force has appeared like the wave. It is thought that it is because Wabing happens because the ball is faced with the end cap or the main body of the carriage, and the load cell had received it as an impact.

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In this research, we tried an examination for the improvement of stiffness of the pivot bearing with multiple degrees of freedom by using the FEM analysis. Design parameters were set up in 2-DOF part of the pivot bearing and we could show the guidelines of the higher internal structure of the stiffness from results of FEM analysis.

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In this paper, a new design of an aerostatic journal bearing with porous floating bush was proposed and instability of proposed bearing at high speeds was investigated experimentally. Test spindle supporting by proposed porous floating bush was constructed and succeeded in rotating a 12mm diameter shaft over 300,000rpm. It is consequently found that using the proposed floating porous bush can greatly improve the whirling stability of a rotor at high speeds.

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This paper describes a 5-DOF controlled maglev actuator for electrical discharge machining. This actuator is compact enough to be attached to conventional electrical discharge machines. The actuator can not only improve machining speed and machining accuracy, but can also be used to realize micro-machining. The experimental results show that the maglev actuator has better than 1μm positioning resolution, a bandwidth greater than 120Hz in the 5-DOF directions, and a positioning stroke of 2mm in the thrust direction. Moreover, the maglev actuator was attached to an electrical discharge machine. Stable magnetic levitation of the spindle shaft during electrical discharge was verified. An electrical discharge machining experiment was executed and a hole of φ1.7mm was machined with the maglev actuator.

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This paper presents a new ultraprecision alignment device with high load capacity, which is targeted for ultraprecision bonding in a vacuum. The ultraprecision bonding is recently needed for emerging production technologies such as nanoimprint, MEMS and WOW. The device is driven by 'Walking Drive', which is an unique driving method to realize ultraprecision positioning with long stroke by utilizing piezoelectric actuators. The method is suitable for high load capacity and the ultraprecision positioning in a vacuum. Mechanical parts of the device are designed by utilizing FEM analysis, so that the device has a high load capacity of greater than 1 ton. It is confirmed experimentally that the developed alignment system has the high load capacity and also fine positioning resolution of less than 10nm.

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