This paper describes the present state of the international standards relating to the machine tool technology. There are eight standards for evaluating the performance of the machine tools; geometric accuracy, positioning accuracy, thermal distortion, circular motion, noise emission, diagonal displacement, axes of rotation and vibration levels. Those are fundamental items in the performance evaluation. In addition, a new work items for machining centers are discussed.

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This paper deals with a real time scheduling system of a holonic manufacturing system for machining process. The holonic manufacturing system was proposed by HMS cooperative research project aiming at realizing more flexible control structures of the manufacturing systems which can cope with the variety of the products and the unscheduled disruption, such as status changes of equipment and input of high priority jobs. Decision-making procedures of individual holons are discussed in the paper to establish a decision making process based on effectiveness for the holonic real time scheduling systems.

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In the manufacturing process, workpiece fixturing is essential process for high accuracy machining. However fixturing process has depended on skilled workers because many requirements of knowledge and skills are involved in this process. As a result, skilled worker impose heavy workload and production time is long. In order to reduce the production time and workload, it is necessary to automate the fixturing process. In this paper, workpiece fixturing automated planning system on 3DCAD is proposed. This system is composed of Fixture Planner and Fixture Selector. Fixture Planner determines clamping and locating points and Fixture selector select suitable fixture devices from fixture database automatically. Moreover, the algorithm of this system is mentioned. And an example of this system is presented.

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Recently, an attempt of intelligent machine tool using open CNC control unit and network communication has been discussing. The development of sharing the machine tool and product information is progressing. We are challenging the development of the machining processor that has the database of machining condition, process design and so on, and can treat various information through the network. Thus, the machining processor can control a process and make a machining strategy based on machining prediction. Furthermore, it can observe a machining situation using attached sensors, and has the function made to reflect in a machining strategy. The machining processor can perform self-machining by inputting only 3D-CAD data. This paper describes the development of network communication software for monitoring and operating a machine tool from a remote PC. The developed software will become the future foundation of the machining processor.

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This paper describes a method for constructing CAM systems in the Network Computation Environment. In general, CAM systems are developed as one application system for generating NC codes for target machines. However, structures of target CNC machines have usually some differences, so, post-processors convert suitable NC codes for target machine tools and CNCs. Manufacturing systems consists of CNC machine tools, AGVs, host computers and so on. These are controlled by computers and connected each other by general network technologies. Such network environments are regarded as network computation environment that can apply general network protocols. This study aims development of CAM system which can be change configurations of system according to target CNC machine tools and requirements of operators base on distributed computation ideas.

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High productivity machine tool system has been developed by using the network technology. The operation result can be monitored by PC server. The CNC data can be exchanged between CNC and PC.

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This paper deals with the development of high speed and high accuracy machining system, which is able to compensate for the effect of a tool deformation, a motion error and so on, based on servo data. The proposed system has two functions, which are newly proposed, to realize high speed and high accuracy machining. One is the geometrical interpolation function, which directly generates servo data from geometric model. The other is the error compensation function, which estimates machining errors by simulating using servo data, and compensates for these errors based on servo data. The servo data is a position data calculated by interpolating and smoothing in each servo sampling cycle. In this paper, the motion error is compensated as an example to verify proposed system. As a result of compensate simulation, it is evident that proposed system is able to reduce motion error using estimate compensate method.

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This paper deals with a precision grinding of none-axis-symmetric aspherical surface by use of a resinoid bonded diamond wheel. Ultra-precision grinding system of none-axis-symmetric aspherical surface was developed. In this system, a resinoid bonded diamond wheel was scanned on the workpiece surface 3-dimentionally controlled with 1mn resolution by linear scale feedback system. At first, the effects of the wheel errors on the workpiece form accuracies and surface roughness were simulated and its compensation methods were discussed. Secondly, the effect of wheel scanning direction on the workpiece surface roughness was researched experimentally. Finally, the none-axis-symmetric aspherical molding dies of a fine grain tungsten carbide were tested with a resinoid bonded diamond wheel to evaluate grinding performance.

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The demand for high precision aspheric lenses has recently been increasing. In this study we will introduce a process that uses a parallel grinding method to produce an aspheric mould made using a super-hard alloy and a correction grinding technique. Also, we will demonstrate the use of different porous resin-bonded diamond whetstones to grind a mould and will review the effects of the different whetstones on precision and surface roughness.

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The new design of a fresnel lens refracting a cold-neutron beam is proposed in this paper. The authors applied an ultraprecision electrolytic in-process dressing (ELID) micro-grinding technique using cast-iron bonded diamond wheels whose edges have been sharpened by electrical and mechanical processes to fabricate the element, and successfully obtained the required element with a sharp and smooth V-faced fresnel structure using MgF_2 glass. And relationship of the form accuracy of fabricated Fresnel lens and the change of grinding wheel shape had discussed.

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ELID (Electrolytic In-process Dressing) grinding technique can achieve high-efficiency grinding, and ultra-precision mirror surface grinding has been able to obtain mirror surface finish easily for hard and brittle materials. We are developing a new ultra-precision mirror surface machining system with ELID. This machine is Ultra-precision Rotary Grinder "RG-800" that has a very large rotary table (size : φ800mm) and it can be controlled at a feeding resolution of 10nm. This paper introduces the concept of the developed ultra-precision rotary grinder with ELID, the specification, and trial of ELID-grinding of Si wafer. In the future, this technique can be applied to produce ultra lightweight mirrors of next generation space telescopes.

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Grinding performance of fine abrasive grinding wheel to Quartz-Crystal were investigated. The grinding wheel were fabricated using a ElectroPhoretic Deposition phenomenon, it was called EPD pellet. In this study, Silica and Alumina powder were applied as abrasives for EPD pellet. Mirror surface about 10nmRy could be obtained by Silica and Alumina EPD pellet, but Grinding efficiency of Silica EPD pellet were better than Alumina.

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The following manuscript offers an explanation about a system and tool database which can increase the effectiveness and practical output of those using 3D profile machines to manufacture Die and Mold. Increased effectiveness is enabled by information that is supplied by the NC operator during the upper manufacturing process. This information sets up the conditions (or choice of tool) for manufacturing. The tool database houses all the data (including figures, elements and the condition of tools) under unified control and, consequently, is able to adjust the choice of tool by defining the aim and status of manufacturing. Working in unison, a CAM system and tool database will increase effectiveness at the place of machine operation.

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This paper describes a tool management system based on analytical approach and database. At first, cutting force and tool deflection of tooling system are calculated. Using these analytic values, cutting condition can be predicted in advance and the tool selection and the decision cutting conditions, that to need the experience and the practical background of skilled engineers become easy. Moreover, by accumulating the past milling operations as a database, know-how can be reflected. By these two methods, we can get tool shape and cutting conditions suitable for the given milling operation.

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Die and mold production requires high quality finishing and severe cost reduction. So to determine the cutting condition is very significant. In this study, a simple estimating test of cutting performance for end milling is proposed. A pre-hardened steel was endmilled in side cutting method under thevarious cutting conditions. Surface roughness, cutting force and wear width aftter endmilling of 2.5m cutting length are investigated. Based on the results obtained. through the simple estimating test, wear test was conducted. Wear width on thecutting edges stayed within 0.1mm after endmilling of 100m cutting length.

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Tool damage detecting system has been developed by using a wear sensor-integrated cutting insert and an eddy current type proximity switch. A beltlike TiN coated layer on cutting edges was used as the sensor. The TiN layer has good electric conductivity, so that when the layer is damaged, an electric resistance of the layer becomes large or infinity. To detect the conductivity of the sensor without wire, a resonance circuit consisted with the sensor, a coil and a capacitor was used. The coil of the resonance circuit acts as a metal to the eddy current type proximity switch when the sensor has low resistance, while the sensor becomes high resistance, an electric current becomes small and the coil can not act as a metal anymore, so that the switch can detect the breakage of the tool.

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If a machine spindle bearing dia. (d) x Max. min-1 (N) of the machine, has a value greater than 1,500,000,then we would class it as a "High Speed Machine", Taking into account the characteristics of modem tooling system, it is evident that conventional tooling system will not allow them to perform at 100% of machine capability. The high speed & hogh precision tooling system must be utilized for higher quality surface finish, extended cutting tool life and reduced machine cycle times.

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Minimum Quantity Lubrication (MQL) method is one effective solution to environmental problems. It can not only reduce significantly the amount of a cutting fluid but also elongate preferably tool life.

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A dicing blade is widely used for cutting of hard-brittle materials, such as crystal and a silicon wafer. Roughly classifying to the blade that is utilized generally, there are an electroplated metal bond blade and a resin bond blade. Compared with the metal bond blade, the resin bond blade has some merits such like the low consumption current value of the blade spindle motor during the processing and the high surface quality of the work-piece although the machining effciency falls a little. However, since the light curable resin blade did not have electro conductivity, the zero point detection function of the present machine was impossible for it. And then by adding with electro conductivity filler or resin, we developed a new electro conductive dicing blade.

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The excimer laser machined diamond has many posts which correspond to the grits on a grinding wheel. This is composed of a large diamond chip (about 2mmx2mm square), which has 10μm high posts that are 3 to 5μm square. The characteristics are : a) high grit distribution density; b) uniform cutting edge; c) uniform grit projection height; d) uniform grit crystallographic orientation; and d) no contamination, because of no heavy metal. Post motion by the ultrasonic excitation achieves an intermittent removal mechanism for a critical depth of cut and, as a result, depending on the number of posts, makes it possible to make a very large total depth of cut in a brittle materials machining.

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This paper reports ultra fine plastic forming of hard brittle materials. Soda glass, quartz glass, quartz and silicon were examined by a nano indentation tester specially designed for this study. SEM observation showed that soda glass is available for ductile plastic deformation up to 300nm in depth. On the other hand, quartz is so brittle that all indentation traces caused cracks. Then, effects of deformation overlap were studied. When distance between traces was so small that plastic deformation zone overlaped each other, the traces were cracked even though their indentation depth was smaller than the limit of ductile deformation, Deformation by a lattice pattern indentation was also examined.

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To understand the mechanisms of material removal at extremely small depth of cut and brittle-ductile transition in material removal process, molecular dynamics (MD) computer simulations of microcutting of defect-free monocrystalline silicon are carried out. MD simulations show that chip removal under nanometric undeformed chip thickness takes place in ductile mode as a result of "viscous flow" of amorphous region following the phase tramsformation from crystalline to amorphous by plowing of cutting edge. The work surface shows amorphous structure with large tensile residual stress. The simulation also suggests that the tensile stress level intermittently generated as a result of discontinuous chip forming increases as the undeformed chip thickness increases. Therefore, in case of cutting under large undeformed chip thickness, brittle mode material removal and/or sub-surface damage may take place even on a defect-free brittle material.

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This paper deals with analysis of the cutting mechanism of ball end mill for milling of inclined surface. At first, modeling method for a tool and a workipece by 3D-CAD and calculating method of cutting area are shown. Secondly, cutting areas are calculated by the 3D-CAD models and cutting force are obtained by cutting tests. And also, the relationship between cutting torques and estimated values as cutting performance and inclined angles of the workpiece are discussed by the results.

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The objective of this study is to clarify the optimum direction of tool revolving axis where the machining error of the surface geometrically becomes the minimum in 5-axis machining. This paper describes the geometric calculation method of mashined surface and the relationship between shape of machined surface and position of cutting edge. In the result of the analysis, both the best and the worst orientation were found at very small tilting angles. In the worst case, the trajectory of cutting edge generates the complicated surface, because of the stationary point of velocity along feed direction which locates inside of the machined region rather than outside in the best case.

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This paper presents a new analytical method to estimate the thickness of an undeformed chip in ball-nosed end milling. It has been firstly pointed out that the geometric situations on the determination of the thick-ness are categorized in three cases based on the relationship among the milling parameters. Secondly each corresponding case has been reduced into a comprehensive equation with introducing a coordinate system of tool axis orientation. Thirdly "backward cutting" near the center of tool is pointed out that is irregular interference between the flank and the workpiece. So "backward cutting" occurs a non contact part on the cutting edge. And a condition of "backward cutting" has been clarfied. An area of "backward cutting" in a ball-nosed end mill is shaped circle that exists beside the center of tool axis.

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In this paper, the flank wear and the surface roughness of machined surface are investigated by high speed milling of hardened steel for a small size ball end mill using a high speed spindle attachment. And also it is investigated that the influence of a tool life on the inclination angle of work piece and the minimum quality lubrication (MQL) method. By the results, it is shown that the long tool life and the small surface roughness are obtained by the conditions of step up milling, down milling and the MQL method to end point of cutting. But bidirectional milling is most efficient method than other type of milling.

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Cutting temperature distribution along the curved cutting-edge of small ball endmill is measured with an three-color infrared radiation pyrometer using an optical fiber. The high speed air spindle unit is adopted to the ordinary milling machine so that the maximum spindle revolution of 40000rpm is attainable. The ball radius of the carbide cutter is 3mm and the side cutting of carbon steel at spherical ball is executed without cutting fluid. The influence of spindle rotational speed, radial depth of cut and feed per tooth on temperature distribution at the flank face are examined. The maximum temperature about 700℃ is obtained at the peripheral cutting edge and it decreases along the ball cutting-edge toward the ball tip. The relatively large temperature difference arises along the ball cutting-edge at higher spindle revolution because the cutting speed depends on the local tool radius. The depth of cut and feed per tooth, on the other hand, affect the overall temperature at the ball cutting edges.

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Report on the result of invesrigation about the possibility of high speed and high efficient milling with carbide end mills.

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Textured surfaces, that have periodic regular structures, create various functions such as optical filters, anti-friction surfaces and so on. This paper describes the latest and attractive processes for texturing, in which the results of survey in abroad are included. The processes are either of removal, deformation, deposition, or pattern transfer technique and typical examples are shown. Also, the typical applications in various fields are introduced.

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Clearance at the interface of two solids in contact should be evaluated for sealing gas leakage. In this study, first of all, we designed experimental apparatus. It enabled us to detect the gas leakage in the sensitivity of 1.0×(10)^<-8>(Pa・m^3/s), which is equivalent to the clearance of 10&acd;50nm. Next, the relation of gas leakage with the experimental parameters such as surface roughness of interface, contact pressure, vacuum pressure, etc. were measured for the purpose that micro-space at the interface should be investigated. Namely, we tried to estimate the micro-space quantitatively based on the relation between the clearance at the interface of two solids metals in contact and their surface roughness. As a result, it becomes clear that qualitatively theoretical characteristics correspond comparatively well with experimental ones. However, the analytical values don't agree quantitatively with the experimental ones, approximately doubled. It would be caused by pressing down of tops and rising up of the valleys of the surface roughness due to plastic deformation of asperities in contact.

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In this paper, the generation of plastic regions in work surface layers in the indenting process is discussed analytically and experimentally, in order to optimize the process conditions to produce the desired residual stress of a blast process. Work surfaces were covered with a large number of uniform dimples at a regular pitch, formed as 20μm in spherical radius, on annealed 0.5% carbon steel. The results demonstrated that the depth of a plastic region and the strain of polycrystals in a work surface layer using the blast process can be estimated according to those in the indenting process. The maximum depth of plastic regions in the FEM analysis is similar to the both processes.

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In this paper, flow characteristics of low viscosity fluid in submicron gap is investigated. Submicron gap is formed between aluminum and optical glass which ion milling is conducted. Micro texture is formed by V-groove on aluminum, and influence of groove pitch, depth and radius on flow rate is investigated. It is found that flow rate is controllable in the same gap by groove parameters.

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The influence of grinding fluid on ductile-mode ultra-smoothness grinding of fine ceramics using #140 coarse diamond grinding wheel is examined. The effect of grinding fluid on the ductile-mode ultra-smoothness grinding is ascertained. The effect for Al_2O_3-TiC ceramic is larger than silicon carbide. The ultra-smoothness surface below 40nm(Ry) or 5nm(Ra) in 3D measuring area of 256μm is attained.

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This paper deals with the grinding performance influenced by micro-deformation and macro-deformation. Grinding test was carried out using two wheels, which are made of different elastic modulus reins. As a result, it appears that micro-deformation influences the grinding force and the surface roughness, whereas macro-deformation influences the workpice dimensional accuracy. It is concluded that the diamond wheels that have high micro-deformation and low macro-deformation are required for high accurate mirror grinding.

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This paper presents the transition between plastic deformation, ductile and brittle cutting in a high speed micro glass cutting. Experiments with the small inclination of the workpiece to give a gradual increase of the depth of cut show that there are three characteristic phases during the cutting. These are characterized as follows; (i) only the thrust component of cutting force is measured, (ii) the principal and thrust components of cutting force are measured and (iii) the variance of cutting force becomes larger. Machined surface conditions observed by a laser micro scope and a surface profiler corresponding to the three phases are examined. Especially, the phase (i) seems to be deformation by densification of a glass. In the last of the paper, an application cutting using the phase (i) to make a deep groove is presented.

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Abrasive Jet Machining (AJM) is a new concept in blast processing. The mechanism involves the controlled injection of a fine abrasive medium onto a substrate material using compressed air as a carrier. Conventional methods of blast processing have commonly been used for ground works or for deburring. They can also be used to create decorative characters or geometric patterns on a surface. With these techniques, the target area is selectively masked and is then blast processed over the mask so that the desired patterns are produced. On the other hand, the AJM technique uses a new design of nozzle to precisely control the volume of abrasive, and thus enables us to achieve abrasion in specific desired areas without the use of masks. In this presentation, we will first explain the theory behind the AJM technique and will then introduce some examples of the process.

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This report describes the development of the slurry-ice jet polishing (SIJP) device for the polishing of the micro-aspherical optics, which is capable of intermittent blasting of slurry-ice. The SIJP process is similar to an ice jet machining (IJM). SIJP uses fine ice powders of colloidal silica, which are produced under the low temperature condition of -150℃ or below. As the ice jet stream from the nozzle is focused onto the workpiece, small part of micro optics can be polished. The blasted slurry-ice is melted and has no influence upon the environment of production processes. We investigated the blasting characteristics and the possibility of the SIJP process. It was clear that the SIJP device can blast slurry-ice and that the BK7 glass material can be polished.

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In 3D measurement using electron beam you can obtain extremely high precision information for an area electron beam can scan. However, there has been a strong demand for high resolution measurement of wider areas. This system, which is capable of stitching multiple image fields captured in high precision, now satisfies this demand. Problem solutions in stitching and data obtained are introduced below.

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This paper presents a super wide range surface form measurement method based on a stitching technique of the data of precision optical microscopes. This method intends to multiscale measurement of precision element surface, especially super precision machining part which tends to have white spectrum of surface profile. In this paper the precision die form is expected to measure three dimensionally from micro asperity profile to precise form profile continuously. In these applications some stitching techniques like plane surface, cylindrical surface, connection in height direction and that in angular direction, are proposed and presented.

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The present report describes the suitable in-situ scan of a laser stylus for point measuring of free surface with a machining center. The attempts were made to improve the measuring accuracy using numerical control function of G02 and G03. That is, we proposed a new measuring method that the laser stylus was scanned around a measuring point on the free surface, The experiments were done to measure the ground surfaces and the end-milled ones by this scanning method. As a result, it is clear that there is proper radius to scan a laser stylus according to surface roughness

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In the areal surface profile measurement, the sampling distance is very important when using a point-type displacement sensor. Firstly, it is essential to reveal the lateral resolution of the sensor so that the adequate sampling conditions for obtaining representative discrete point data could be determined. Then, by knowing the wavelength band for conventional straightness and flatness assessments, we introduced a signal conditioning process in the long-wave side of the processed data. As to the final sampling distance, we applied auto-correlation techniques to the wavelength analysis of surface-dependent profile data.

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