An integrated simulation and development environment for the digital controlled AC servo system is proposed in this paper, which is based on personal computer to be applied to simulate, optimize and adjust the control code, control parameters and control models of system without any hardware. It’s an exploration for improving the digital controlled AC servo system’s developing condition. Realization of this method will greatly reduce the time and cost in developing servo system and improve the performance of system, whose validity and feasibility are verified by detailed simulation and experimental results.

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The application of state observer structures in digital current closed-loop control based on integer operation for permanent magnet synchronous motor (PMSM) is considered. The state observer predicts the currents, and overcomes the filter delay as it suppresses the noise of samples. Accordingly, the resulting control structure is shown to heighten the response frequency and to improve disturbance rejection capabilities. Experimental result generated by a prototype controller demonstrates the predictable effects of state observer and the improvement of system performance. And the influence of parameter variation on the observer response characteristic and system performance is discussed.

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In EDM of deep hole, the machined hole generally becomes concave shape by the occurrence of secondary discharges in the side gap. By using flange type electrode, the occurrence of secondary discharge could be reduced. In this report, the effects of the shape of flange type electrode on the machined result were investigated. Experimental results clarified that a straight deep hole could be attained by using flange type electrode with sufficiently large step, and the diameter of machined hole decreased with an increase of the step difference. Also, EDM performance became better, even if a EDM machine with ball screw drive was used.

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The purpose of this study is to develop a new type of wire electrode, in which piano wire with very high tensile strength is coated with electrically conductive layer, such as brass or zinc, in order to attain high speed and high precision wire EDM. In this report, using a trial-made thin wire of 50μm in diameter, the optimum thickness and quality of brass layer were experimentally investigated for higher performance fine wire EDM. Furthermore, the influence of the tensile strength of piano wire used as a core wire was discussed. As a result, the coated brass with copper content of 60-70% is effective and the thickness of coated brass is needed to be more than 1.45μm for high removal rate.

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Advanced engineering ceramics is widely employed in modern industry. This paper investigates the electrical discharge machining (EDM) of ZrO₂-based ceramics by assisting electrode method. The theory of assisting electrode method is introduced. The machining mechanisms were investigated through the SEM micrographs, XRD analysis and the machining waveforms. Some ZrC material can be found on the machined surface. The SEM micrographs show that the material removal mechanisms change with the electrical parameters. A 30~50μm material changing layer can be found on the machined surface through the SEM micrographs. Some work-pieces have been machined successfully by the assisting electrode method.

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If hard layers could be formed with the electric discharge machines (EDM) now popularly used for material removal, the time and cost of producing dies and machine parts would be greatly reduced. The wear properties of hard layers formed on stainless steel using EDM were studied. As a result, it was found that the hard layers formed with TiH₂ green compact electrodes are three to four times more wear resistant and the layers formed with TiC semi-sintered electrodes are about 10 times more wear resistant than surfaces with no hard layer.

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A new mechanism design using a magnetic force with high efficiency to assist discharging dregs out of the electrode gap during the electrochemical finishing on the surface finish process that follows end-turning is investigated. A higher current rating with magnetic-assistance reduces the finishing time and avoids the difficulty of dreg discharge. Providing a large magnetic field intensity or using a small distance between the two magnets produces a larger magnetic force and discharge ability and better finishing. A large rotational speed of the workpiece and electrode produces better finishing. Pulsed direct current can slightly promote the effect of electrochemical finishing.

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An effective and low-cost finish processes through burnishing assistance following electrochemical finishing after screw machining offers a fast improvement for the surface roughness of the screw-surface is a new application in the screw finishing process. The burnishing-tool uses ceramic material connected with the electrode and moves, following the electrode, to burnish the workpiece. The results show that the use of a higher rotational speed for the electrode and burnishing-tool is advantageous to the finish. Pulsed direct current can slightly improve the finish effect. A partial form with a thinner heavy section performs the best finish effect in the current investigation.

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A new surface modification for bio-titanium alloy products by EB polishing is proposed. In this EB polishing method, high energy density EB can be irradiated without concentrating the beam. Therefore, large-area EB with a maximum diameter of 60mm can be used for instantaneous melting or evaporating metal surface. Experimental results made it clear that surface characteristics, such as repellency, corrosion resistance and coefficient of friction could be improved simultaneously with the surface smoothing in a few minutes under a proper condition. Therefore, EB polishing method has a possibility of high efficient surface smoothing and surface modification process for bio-titanium alloy.

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We developed a conductive rubber-bond grinding wheel for ELID grinding. The grinding wheel is composed of rubber, carbon, and abrasives, and was designed to demonstrate ELID effects (continuous grinding ability) by the excellent finishing effects of rubber and conductivity ensured by carbon. The prototyped grinding wheel was a #1200 conductive rubber-bond grinding wheel using Al₂O₃ abrasives. Grinding experiments of mono-crystalline silicon were carried out using this grinding wheel, and it was found that stable grinding without loading could be realized by adding ELID grinding.

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In this study, we have performed efficient and high-precision grinding of cemented carbide alloys with a newly developed grinding wheel, and investigated the ground surface characteristics in detail. The processing results showed that final finishing using the Chromium bonding #8000 wheel produced an extremely smooth ground surface roughness Ra of 4 nm. And, the Cr-series exhibits a strong chemical adhesion because the Cr elements that penetrated and diffused into the substrate during the machining process have a strong chemical affinity with the DLC film.

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Grinding forces are very important phenomena of the grinding process. They are also the necessity of the design and the selection for grinder. The higher grinding forces, the more difficult removing material from the workpiece surface. In order to obtain more knowledge about the grinding mechanism of ceramics and steels, a comparative study of ELID (ELectrolytic In-process Dressing) grinding forces of these two kinds of materials was investigated on the same experimental conditions. This experiment was carried out on a surface grinder. Four types of materials, such as ceramics of SiC and ZrO₂, steels of SKD11 and STAVAX, were selected. In grinding process, grinding forces were measured by a three-component forces dynamometer. It was found that the grinding forces of SKD11 and STAVAX were greater than these of SiC and ZrO₂ on the same conditions. Finally, these phenomena were explained on the basis of the cutting principle.

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This paper proposes new micro fabrication processes of metallic materials by combination of nano plastic forming, plating and polishing. The process is separated into 5 steps; nano plastic forming, nickel plating, peeling, polishing, and picking up. Three kinds of metallic structures were fabricated by combination of these steps; micro structured foil, micro composite surface structure, and miniature mechanical parts. Each step was tested experimentally in the paper. It was confirmed that the proposed processes are useful to manufacture various kinds of micro devices.

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This paper reports studies on new nano fabrication technology to control crystalline structure of metallic material. Wedge tool indentation tests were conducted on a single crystal copper specimen by using nano forming tester, and crystal rotation by plastic deformation was studied. Cross sections of indent grooves made by nano forming tester were machined by FIB, and distribution of crystal orientation on the cross section was analyzed by the method of EBSD. Results revealed that crystal rotation around an indent groove is separated into two zones, and rotation axis correspond with [100] direction regardless of crystal orientation and tool direction. This finding show possibility of crystalline structure control of metallic materials by nano plastic forming technique.

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This study demonstrates the application of dip coating to self-assembly of fine particles on a substrate that is covered with line-and-space pattern of hydrophilic (SiO₂) and hydrophobic materials (OTS). The pattern was fabricated on a substrate by lithography first. The substrates were drawn up from the water-based suspension in which particles were dispersed and the particles self-assembled on the hydrophilic region only forming the packed-structure. Then, contact printing was applied for the patterning to extend the scale. The scale was extended up to 10mm x 10mm while keeping the self-assemble performance.

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Novel type passive mixer that causes the three-dimensional flow was proposed. This mixer consists of the integrated capillary bundle structure. The mixing effect of the cross-linked micro capillary filter was calculated by the Computational Fluid Dynamics (CFD). On the basis of the calculation result, the filter was fabricated by application of the Deep X-ray lithography. To form the cross-linked capillary, it was operated twice exposures. And the fabricated filter was applied to vertical fluid flow operation. This filter could hold and transmit the fluid by the switchover the impressed pressure. Herewith the filter showed availability as high efficiency mixing device.

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This paper reports a new method to magnify the critical depth of hard-brittle materials by the nanoforming process. This method applies electrical current to a specimen during a nanoforming process, which cause temperature rise in the vicinity of the tool edge. In case that a specimen was a soda glass, electrical current was applied through a WC tool, and sufficient concentration of current resulted in apparent increase of critical depth was observed. In case that a specimen was silicon wafer, when electric current was applied only to the specimen, electric current showed little effects on the critical depth.

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Demand for micro-lens molds is on the increase. A desk-top machine tool as a system for the machining of micro-lens molds is expected. However, when a grinding wheel with a small diameter is used, the ELID grinding method experiences a problem related to the installation of the negative electrode.

In this research, for the purpose of machining of a micro-lens mold, we developed a system to realize electrolysis using the small type ELID grinding wheel that did not require the use of the negative electrode. The results indicate the successful development of an ion shot dressing grinding system that uses a nozzle type electrode. As a result, the use of a #4,000 wheel produces a finished roughness of RMS 2.0nm, with good form accuracy was good of P-V 0.8μm.

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In bioengineering, cell manipulations are manually done by skilled operators currently. The operations are tedious and time consuming, yet with very low yield rate. The cell manipulation is highly expected to be automated. In this research, we have developed an automated micro-manipulation system, in which a vision control scheme has been proposed and implemented for feedback control. In this paper, a path control scheme using potential approach and configuration space is newly proposed to automatically generate the tool path for moving. The performance of the new control scheme is demonstrated in a field test.

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In order to use saliva for human stress diagnosis, ELISA (Enzyme-Linked ImmunoSorbent Assay) is most promising, when saliva must be diluted in purified water from about 10¹ to 10⁴ times corresponding to the applied stress markers. A new dilution system with 4 diluting ladders in which each step has 10 times dilutive capability is developed, hence, can realize 10¹ to 10⁴ step-likely. Its performance was tested by having mixed a fluorescent material in pure water and checked its change of intensity, and it is verified that +-20% error for the 10⁴ time dilution target is kept.

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Principle of membrane driven micro-pump was clarified in the previous paper[1], and its fundamental performance has been tested in the current paper. Namely, micro flow rate was measured by PIV (Particle Image Velocimetry) against a membrane displacement that is measured by a laser displacement gauge. The flow rate calculated from the membrane displacements resulted in about 1000 nl/min, on the other hand, the measured one scattered widely centered 300 nl/min. This difference may come from a bubble growth and diffusing process, nevertheless, the prototype seems applicable to a pumping system for μ-TAS, micro-fuel cell, etc.

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Electro-rheological gel (ERG) is a functional material whose friction characteristic varies according to the intensity of an applied electric field. In this study, ERG is applied to the fixture element for a silicon wafer. Silicon wafers are used for semiconductor manufacturing, a process carried out in a vacuum. The purpose of this study is to clarify the basic characteristic of ERG in a vacuum. To investigate these characteristics, several tests were carried out using silicon wafers. In addition, the optimal shape of one-sided electrodes applying the electric field effectively was designed by means of a static electric field analysis.

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A prediction model for surface properties for end mill operations is discussed in this paper. The surface properties are predicted with considering behaviors of cutting edges which include a cutting tool movement, a cutting tool rotation, a cutter runout and a cutter vibration. These models are explained in detail and the feasibility of the surface properties prediction using the aforementioned models is described.

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Machine tools are recognized as key components of manufacturing systems, and product quality and cost mainly depend on performances of the machine tools. Much progress has been made in the machine tool technologies, aimed at improving the performances of the machine tools from various viewpoints, such as accuracy, reliability, productivity, and flexibility. The machining accuracy is one of the most important characteristics of the machine tools. From the viewpoints of the design and the manufacturing of the machine tools and their components, one of the important issues is to clarify the relationships between the kinematic motion deviations of the machine tools and the geometric tolerances of the components, such as the guide ways and the bearings. The objective of the present research is to establish mathematical models representing the kinematic motion deviations of the machine tools, on the basis of the geometric tolerances of the components, and to apply the models to theoretical analysis of the kinematic motion deviations of the machine tools.

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One of the problems faced in turning processes is the elastic deformation of the workpiece due to the cutting forces resulting in the actual depth of cut being different from the desirable one. In this paper, an attempt has been made to describe a cutting mechanism suggesting that the above problem results in an over-dimensioned part. Consequently, the problem of determining the workpiece elastic deflection is addressed from two different points of view. The first one is based on solving the analytical equations of a cylindrical workpiece due to cutting forces. The second approach focuses on the evaluation of deflection in a cylindrical workpiece using Finite Element (FE) software ABAQUS. The reliability and verification of the analytical method and software model is demonstrated by comparisons with turning experiments. The accuracy and simplicity of the proposed models make it suitable to predict and/or complement experimental investigations.

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In order to solve the job shop scheduling problem (JSSP) better, a new hybrid genetic algorithm (HGA), which combines genetic algorithm (GA) and simulated annealing algorithm (SA) is proposed. In HGA for JSSP, the fitness and target value of algorithm are represented by completion time of jobs. HGA proposed in this paper can avoid such disadvantages as premature convergence and low stability. Experimental results demonstrate that the proposed algorithm does not get stuck at a local optimum easily, and it is fast in convergence, simple to be implemented. At last, several examples testify the effectiveness of HGA for JSSP.

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Unexpected disruptions often occur in the manufacturing systems. The manufacturing systems cannot execute the manufacturing operations in accordance with the predetermined production schedule due to such disruptions. Therefore, a systematic scheduling method is required to cope with such disruptions. In this research, distribution of processing time is described with the normal distribution. The reactive scheduling method for distribution of processing time is proposed in order to modify the predetermined production schedule. And the suitable re-scheduling period is considered through the computational experiments.

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In this paper, we propose a job shop scheduling method to meet due-dates and to minimize overtime as far as possible. The sequence of operations of jobs is determined using the mixture of genetic algorithm and priority rule. The minimization of overtime is carried out by tuning a parameter based on machine loads. Numerical experiments show the effectiveness of the proposed method.

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Trends of globalization and advances in Information Technology (IT) have created opportunity in collaborative manufacturing across national borders. Fixed supply chain optimization strategy has difficulties applying to the flexible, project based manufacturing environment characterize by the involvement of Small and Medium-sized Enterprises (SMEs). This research proposes a three echelons dynamic supply chain model where the node being focused autonomous ly negotiates contracts with downstream client and upstream suppliers based on parameters derived from a reactive scheduling engine and a inventory management system.

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Several machine tool vendors have developed maintenance support systems using the internet, but the systems are dependent upon each particular machine tool vendor. Moreover, most systems merely monitor Open NC’s console. Consequently, these maintenance systems cannot accommodate other resources such as materials and documents. For that reason, this study examines a portal collaboration type operation and maintenance support system. The system accommodates a controller’s information along with other resources. This paper describes the system concept and a document management system that collaborates with the 3-D Remote monitoring system as one system component.

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This research proposes a new model representing multi-layered dynamic supply chains. The proposed model consists of three kinds of components. They are clients, manufacturers, and suppliers. The manufacturers, proposed in this research, not only generate the orders to the suppliers but also generate the offers to the clients. The manufacturers continue to modify their production schedules after sending the orders to the suppliers, in order to get the contract with the clients, even if the possible delivery time from suppliers do not satisfy the required delivery time from the manufacturers. The effectiveness of the proposed model is verified through some computational experiments from the viewpoint of the completion of the contracts.

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Products refurbishment and the logistic systems are discussed toward environment conscious product lifecycle management. Three alternative systems are enumerated and their environmental impacts are compared. The first system implements the refurbishment at the products users, the second does it at the dealers, and the third does it at the manufacturer. Depending on the place performing it, the necessary logistic systems are varied. Further, a performance level of the refurbishment depends not only on the place but also on the products structure. Then, the environmental impacts from the systems are formulated and dominance relations among the systems are clarified.

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Increasing productivity of resources is a major approach in the framework of sustainability in manufacturing. The manufacturing industry can reduce the consumption of resources and production of waste by applying more efficient design techniques. We focused on simplifying the structure of a product as the key method of design for environment. The removal of redundant components, by extracting the ideal simplified structure, decreases manufacturing costs and, at the same time, increases the resource productivity. We propose a methodology for product simplification that can be applied to general products and developed a product design support system by using information on the geometry and the connectivity of the product’s components. A case study based on models of a vacuum cleaner and an inkjet printer showed the effectiveness of the methodology.

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In these days, modular design of a product is becoming important even for environmental conscious design in order to improve, e. g., reusability, disassemblability, and recyclability. In order to derive a feasible module structure, not only environmental aspects but also geometric information bears important roles. This paper presents a modular design methodology for life cycle engineering that proposes module structure by using information on geometry and product life cycle. The case study of an inkjet printer revealed that the derived modular structure satisfies the various demands from product life cycle with keeping the geometric consistency.

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A sustainable society requires that products be environmentally friendly and conform to the market needs. According to this background, a tool named Extended Eco-Value Analysis has been developed by improving existing Eco-Value Analysis that allows product developers to analyze the functions of a product from economic costs, customers’ importance, and environmental impacts. However, a result obtained from the application of this Extended Eco-VA is open to discussion. Therefore, this paper proposes a new method to obtain more accurate customer requirements. Furthermore, the authors improve the product evaluation criterion that is adopted in Eco-VA by considering the above method.

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The chip breakability of age-hardened Al-4.0mass%Cu alloy and Al-5.6mass%Cu-4.0mass%Si alloy during turning with carbide inserts (K10) were examined. In dry cutting, overaged materials showed increased chip breakability compared to underaged and peakaged materials for both Al-Cu and Al-Cu-Si alloys. This was considered due to increased adhesion of workpieces to the surface of the tool. In contrast, in wet cutting, the chip breakability of Al-Cu-Si alloys increased largely. This increase of chip breakability in Al-Cu-Si alloys is due to the decreased strength of chips as a result of infiltration of cutting oil to the microcracks in chips.

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The machinability, especially generation of surface defects, of Ti-47.7at%Al fully lamellar structure was examined by orthogonal cutting. Although surface defects were observed in every cutting condition, the machined surface tended to be significantly smoother as the depth of cut decreased 100μm to 20μm, and the rake angle of the tool was changed +5° to -5°. The surface defects were categorized into 2 groups depending on whether it is caused by lamellar layer, or lamellar colony boundary. It is discovered that the former is generated preferentially onto certain lamellar angle, and the latter showed no relation to the lamellar angle.

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For the planarization process of LSI wafers, metal bumps covered with polymer glue are machined with a diamond tool. In this study, the deformation process and temperature field in this process are analytically simulated with FEM. In order to analyze the cutting process for resin which has a viscosity, the cutting simulator first has to treat the visco-elastic-plastic material property. Secondly, to analyze the cutting at the micro-meter level depth of cut, the analysis model was scaled down. Finally, to simulate the cutting process of a LSI wafer, PVC and 70% Cu-30% Zn brass were assigned a resin and a metal part, respectively.

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Tool life is an economic factor in machining. In this study, the machinability of microalloyed steel (30MnVS6) and quenched-tempered (QT) steel (AISI 5140), at different cutting condition, was investigated. An experimental investigation was conducted to determine the effects of cutting speed, workpiece material, feed rate and hardness on the flank wear and tool life of cutting tools in the hard turning operation. It was tried that for any test condition the hardness of the steels became almost identical by using appropriate heat treatment processes. Chip characteristics and chip/tool contact length were investigated. Crater wear of the tools was studied by using video microscope for any material in turning operation. Shear edges and flow layers of the chips were analyzed by scanning electron microscope (SEM).

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The cutting process applying cryogenic cooling is discussed for machining micro grooves on soft polymer materials. In this paper, the freezing milling method using liquid nitrogen is applied for the micro grooving of polydimethylsiloxane (PDMS). It is difficult to machine elastic materials such as PDMS because of their low toughness. However, the elastic properties of soft polymer materials change at temperatures below the glass transition temperature when soft polymer materials change from being elastic to hard. The result of a cutting test shows that micro grooves can be shaped in PDMS by the proposed freezing method, and good machining accuracy is attained.

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This paper describes the processing characteristics of copper which ultraviolet ray was exposed on. The irradiation of ultraviolet ray increased the etching rate of copper, and the surface roughness becomes small. The irradiation by ultraviolet ray improves the surface roughness over all condenses of processing liquid. The minimum surface roughness was obtained at the appropriate irradiate time, pH, and the height of liquid level. The temperature arise of liquid decreases the surface roughness of copper.

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There are growing industrial needs of micro-drilling of engineering ceramics. Among the ceramics, little study was conducted on micro-drilling on silicon nitride. In the present study, micro drilling on two kinds of silicon nitride with different kinds of additives (Si₃N₄ + Y₂O₃ and Si₃N₄ + Al₂O₃) were conducted in ethanol as the cutting fluid. The condition of the spindle rotational speed and the feed rate was clarified for safe drilling. The life of the diamond-coated drill is longer for Si₃N₄ + Y₂O₃ than for Si₃N₄ + Al₂O₃; referred to SiN-W, and SiN-B respectively. It is suggested that tribo-chemical reaction product; silicon alkoxide may effectively protect the damage of the drill point for SiN-W.

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This paper reports on deformation characteristics of a double structure blade under a continuous cutting condition using a crank type machine. From this research, the following results were found: (1) Deformation of the bottom tip at a certain applied force has prevented the blade cutting tip from severely damaged. (2) A plastic deformation was found on the bottom tip at a certain applied force and has resulted in a decreasing of force balance. (3) Crushed tip thickness t_C1 tangency, measured along the blade cutting line showed a little reducing especially at high applied forces resulted from the bottom tip ‘shimming’.

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This paper reports for the cutting mechanism of a thin worksheet on a flexible underlay. To study a cutting performance of a thin sheet with flexible underlays, a 42° center bevel blade indentation test to a 10μm thickness aluminum foil mounted on several flexible underlays were carried out experimentally and numerically. For discussing the effect of the rigidity and thickness of underlay on the cutting characteristic of worksheet, an elasto-plastic finite element analysis was applied to. The following were obtained: (i) the cutting characteristic of worksheet depends on the ratio of worksheet’s yield stress by underlay’s yield stress σ_Ys/σ_Yu; (ii) the separation of worksheet was available for σ_Ys/σ_Yu<4 and it depends on the thickness of underlay.

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This paper describes an application of ultra-precision diamond cutting for a cylindrical micro coil line in a fabrication process by lithography. The coil lines fabricated by UV or X-ray lithography are electroplated by nickel and copper. The direct cutting of the resist and electroplating structure by diamond tool is attempted to finish the flat surface. The fluctuation of the resist thickness is reduced to 1μm or less by diamond cutting. By applying the diamond cutting operation in the conventional lithograph process, the micro coil with the line-and-space of 30μm is fabricated.

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The study deals with the development of fundamental CAPP system for 3-D micromachining. Complicated 3-D microparts can be created by the development of multi-axis control ultraprecision machining centers. 3-D CAD/CAM systems for multi-axis control micromachining are also developed, which save time and labor to make numerical control date. However, operators have to plan the process empirically. The system developed in the study automatically decides the fixing surface and the number of control axis of multi-axis machining center, based on CAD data of the initial shape and the finished shape. The simulations by using various workpiece models show the validity of the system.

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In recent years, the demands for fabricating complicated microparts accurately and efficiently by means of multi-axis control ultraprecision machining centers are increasing. However, the accumulations of various kinds of errors deteriorate the form accuracy of machined microparts. To solve these problems, this study proposes a method to detect the tool tip position by means of electrical conduction between gold-coated non-rotational diamond cutting tool and the workpiece attached to 5-axis control machining center. From machined results with the compensated NC data, it is found that the method proposed in this study is effective to set the tool in the right position.

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This paper reports a newly developed lathe type NC machining device that works in a high pressure chamber, where up to 400 Moa can be applied, in order to realize damage free machining of hard-brittle materials. The machining device equips a turntable and accurate X-Y stages, whose resolution is less than 1 μm. It is confirmed that the machining device works well even under high hydrostatic pressure. This paper also reports machining test of soda glass plates under hydrostatic pressure up to 100 Moa. Results show that the critical depth of cut can be magnified by high hydrostatic pressure.

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Ductile mode micro grooving with a sharply-pointed diamond tool under three-axis numerical control can fabricate precise micro Fresnel structures on single crystal germanium. However, in a practical durable machining process, the tool tip will wear gradually and finally produce micro chippings at the edges of the micro prisms. In the present paper, a new tool path is proposed in order to prevent the occurrence of micro chippings. The micro fractures occurred in machining can be completely removed during the following cut, thus leave the micro prisms damage free. Experimental results have demonstrated that the proposed method can significantly improve the profile integrity of a Fresnel lens and enable longer effective tool life.

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Ultrasonic machining (USM) is an effective method for machining hard brittle materials. In USM process, materials are removed by accumulation of small brittle fractures made by abrasive grains pressurized by the ultrasonic vibrating tool. The purpose of this study is to fabricate micro grooves on hard brittle materials accurately and efficiently by USM. In this paper, generation mechanism of chippings and deterioration mechanism of machining efficiency are investigated. And application of an electrorheological fluid to USM process is proposed as a countermeasure of these problems. As a result, high-precision and high-efficiency USM machining of micro groove is achieved.

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