In automotive industry there is a growing concern for the total economy of a manufacturing system throughout its lifecycle. In order to decrease its affect on product cost a better utilization of the manufacturing system is necessary. Product family analysis is a means to group products with common manufacturing aspects and analyze its manufacturability in a possible or existing manufacturing solution. The aim of this research is to provide support for product family analysis by enabling reasoning about resource's capability, i.e. what a resource can do and how well it can do it.

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Dimensional tolerances and geometric tolerances of three-dimensional product shapes are very important for manufacturing process control and quality control of mechanical products. The objective of the present research is to develop systematic methods for planning and analysis of the geometric tolerances of the three-dimensional mechanical products. The tolerance zones of the geometric features have been investigated, in the previous paper, based on the definitions of the geometric tolerances, and the parameters have been defined to describe the deviations of the geometric features within the tolerance zones. Mathematical methods are discussed, in the present paper, to estimate the statistical deviations of the positions and the orientations of the geometric features, based on the deviation parameters and the relationships between the datum features and the target features. In particular, emphasis is given to the analysis of the statistical deviations of the geometric features under the MMC (Maximum Material Conditions), which specifies the interaction between the dimensional tolerances and the geometric tolerances. The proposed method is applied to the analysis of the deviations of the geometric features, to which both the dimensional tolerances and the geometric tolerances are required.

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As turning parameter optimization is highly constrained and nonlinear, it is necessary to investigate the suitable penalty strategy in such case. In this work, parameters for single pass turning operation are optimized. Here unit production cost is the objective function and limits of the cutting force, power, surface finish, stability condition, tool-chip interface temperature and available rotational speed in the machine tool are the constraints. The optimum cutting parameters and constraints values obtained by two different approaches: GA with SOAP and GA without SOAP are investigated. The result shows that GA with SOAP performs better than the GA without SOAP. The feasible ratios of the solutions based on different constraints at different generation are also discussed in this paper.

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This paper consists of: (1) Necessity and purposes of the research, (2) Mechanism of non-circular gears and the relationship between a shape and its transmission motion or velocity, (3) Design of teeth and pitch curves, such as an involute curve as a tooth curve, and an ellipse or a free-form curve of B-spline as a pitch curve defined by analytical geometry methods, (4) Calculation and adjustment of the number of teeth, (5) Distribution and trimming of teeth, (6) Creation of a 3D model and its CNC machining program of the gear and (7) Discussions and conclusions.

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To test an air-bearing displacement probe for aspherical surface measurement, measurements at various contact angles are carried out. A laser interferometer is employed as the reference in the measurement. Two methods are also presented to measure the profile error of the probe sphere through scanning a sample sphere. In the first method, two repeated scanning is conducted along the redial direction of the sample sphere before and after a small rotation of the sample sphere. In the second and the sample sphere is scanned while it is rotated by the spindle. The profile error of the sample sphere can be separated by data processing in each of the method.

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The pitch of machine parts influences its quality and therefore the quality control of pitch by precise measurement is demanded strongly in industries. The measurement of pitch is, however, usually time-consuming process if touch probe is used. Noncontact measurement is also used but it has difficulty in working distance or stability of measurement. In this report, a new noncontact measuring method of pitch is proposed. The image of surface of moving object is taken consecutively and the degree of focusing is evaluated for each image. The pitch is measured by analyzing the whole wave form corresponding to the change of focusing value. The principle of measurement is proposed and the fundamental experiment for pitch measurement is carried out.

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In the semiconductor industry processing and measurement of silicon wafers in the nanometer order are required. Moreover, larger and thinner precise glass substrates are in demand for the purpose of enlargement and weight reducing of FPD. However, the accurate shape measurement of thin-large panels is difficult because of the vibration and deflection due to gravity and clamping forces. In this study, error factors and repeatability in the shape measurement of thin-large panels is investigated using the three-point-support inversion method.

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To separate the errors in rotating spindle, multi-step and multi-probe methods have been developed. However, few researches were reported on high RPM cases. In this paper, an efficient method to analyze the radial errors of high speed spindle in a miniaturized machine tool is proposed. Different speed cases for the spindle are investigated. Firstly, eccentricity error is removed using coordinate transformation. Later, the roundness and spindle errors are separated based on the cut off frequency of a filter used in the present algorithm. The method is effective in determining and analyzing the spindle errors of a high speed miniaturized machine tool.

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The Diffraction Gauge Method, a novel measuring technique based on far-field laser diffraction, has been proposed to measure cutting-edge profiles of micro cutting tools with repeatability of better than 100nm even though on-machine surroundings. In this article, the cutting-edge profile measurements of worn micro endmills (φ300μm) are carried out. Agreement of the tool cutting-edge profiles measured by our method with the image observed by SEM certifies the accuracy of the measurement technique. Furthermore, the automated measurement on the tools is demonstrated for a purpose of duplicating on-machine measurement. Then, wear growth on micro tools are also investigated. The measurement results suggest that the method is available to evaluate the micro tool cutting-edge profiles as an ultra precision on-machine measurement.

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This paper describes a PZT-based fast-tool-servo (FTS) for ultra-precision diamond turning. A pre-loaded ring-type PZT with a maximum stroke of 70μm is employed to actuate the diamond tool attached on the free end of the PZT. The displacement of the PZT is servo controlled by a PID controller based on the measurement result of a capacitance-type displacement sensor integrated inside the PZT actuator. A piezoelectric-type force sensor is coaxially connected on the other end of the PZT for detection of machining force. Investigation of static and dynamic responses of the FTS, calibration of the force sensor output are carried out.

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In this paper, a new principle of Bio-Fuel Cell based on photosynthesis/metabolism without using any mediator was proposed. This bio-fuel cell was named Direct Photo-Synthetic/Metabolic Bio-Fuel Cell (DPMFC) which has a new and simple structure for portable applications. This DPMFC, using polyaniline instead of mediator, succeeded in generating peak current density of more than 35μA/cm^2 with a 10-Ω load, 1.1μW/cm^2 of max power density. This performance is competitive enough with another kind of bio-fuel cell. The benefits of DPMFC are: its ability to produce power in dark/light, un-harmful to living things and no necessity to supply fuel.

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A novel three-dimensional probing technique for micro parts with high aspect ratios is proposed. In this technique, a particle trapped optically at the optical fiber tip is used as a probe for position detection. Numerical analysis about the optical force and detection signal were demonstrated by using finite difference time domain method (FDTD) and Maxwell stress tensor. And also fundamental optical fiber trapping experiments were demonstrated in the water. For the first, a probe sphere was levitated by illumination from the laser, and laser light emitted from the optical fiber successfully trapped the probe sphere three-dimensionally.

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The ultrasonic motor in which structure differs from the conventional ultrasonic motor was invented. In this paper, verification and evaluation of the drive performance of this ultrasonic motor and its application to the catheter medical treatment in a blood vessel were performed. Rotation speed of the motor was measured in the verification and evaluation of a drive performance. Moreover, it succeeded in the underwater drive of the micro motor (diameter is 1.0mm) in application to catheter medical treatment.

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Nanoindentation data reveal interesting behavior in aluminum with various purity levels: 99.9999% (6N), 99.99% (4N), and 99% (2N). Nanoindentation is used to investigate the relationship between the purity level and the mechanical properties at room temperature. Moreover, to clear the differences between microscopic and macroscopic mechanical properties, conventional tensile test and hardness test are performed. It is suggested that the deformation behavior in microscopic scale is different from that in macroscopic scale, and that a perfect crystal is harder than an imperfect crystal. Furthermore, some recovery of the indentation mark is observed in ultrahigh-purity aluminum, caused by the mobility of defects in the sample.

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This paper presents a measurement system based on an AFM to measure large area micro-structured surfaces rapidly, which consists of a compact and precision AFM probe-unit, a linear stage and a spindle. The sample is mounted on the spindle and the AFM probe-unit is mounted on the linear stage. In this measurement system, the sample is measured rapidly in a spiral scanning pattern which is made by rotating the spindle and moving the linear stage in radial direction. Design of the measurement system, results of investigating the linear stage and the spindle performances are described. Profile measurement results of a micro-structured surface is also presented.

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This paper describes a production planning method for reverse supply chains, in which a disassembly company takes reusable components from returned used products and supplies the reusable components for a product manufacturer. This method addresses the issue that the timings and quantities of returned products and reusable components included in them are unknown. This method first predicts the quantities of returned products and reusable components at each time period by using reliability models. Using the prediction result, the method performs production planning based on Material Requirement Planning (MRP). This method enables us to plan at each time period: the quantity of the products to be disassembled; the quantity of the reusable components to be used; and the quantity of the new components to be produced. The flow of the components and products through forward and reverse supply chain is simulated to show the effectiveness of the method.

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This research deals with a dynamic supply chain model representing decision-making processes of individual clients and suppliers, and also negotiation processes among all clients and suppliers. In the model, suitable prices and delivery time are determined based on both the scheduling processes of the individual suppliers and the negotiation processes among the clients and the suppliers. The production scheduling process of the suppliers are newly considered in the model to deal with the trade-off between the prices and the delivery time. The effectiveness of the proposed model is verified through computational experiments from the viewpoints of the prices, the delivery time and the benefit of the suppliers.

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Our objective is to establish a simulation system that can be used easily throughout the manufacturing system life cycle. Therefore, we developed a manufacturing simulation system based on distributed simulation architecture, HLA. However, it is too difficult to apply the system to the implementation stage of the real factory, because the simulation language is not executable on a real device. In this paper, we propose a method and a system for integrating the real devices into the manufacturing simulation systems on the network. This is a distributed real simulation system which consists of a soft-wiring system, a production cell simulator and so on.

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The need of fully automated microassembly systems place specific functional requirements on the design and fabrication of critical equipment elements such as grippers, sensors, manipulators and feeders. The paper provides an overview of current microfeeding technologies for microassembly operations and critically evaluates their applicability and limitations. A new microfeeder design is also proposed based on contactless pneumatic distributed manipulation. By cooperation of dynamically programmable microactuators, a number of feeding functions and even some elementary assembly operations can be achieved.

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Our recent studies for Framed Knowledge Base convinced us of an application for machinery assembly database and as seemingly, the function of 'Association implemented in Framed Knowledge Base is extraordinary among Artificial Intelligence abilities. Physical meaning prevailing between two members at an assembly interface could be identifiable by the 'Association. Therefore, once a certain type of assembly is specified for query, every component attached or connected are retrievable instantly upon request as well as their physical conditions at the interface. Other form of fabrication process, is also conceivable by means of this 'Association. Building scripts for the semantic knowledge is pretty straightforward relying on the actual arrangement of parts and elements, which is approximately proportional to that of physical dimensions. Contrasted with scripts for an accustomed relational database, our scripts for the Framed Knowledge Base is outstanding in intricacy and susceptibility for building query system for a machinery problem interrogation.

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Technical information, such as machining features, type of machining operations and machining conditions, should be represented explicitly and integrated into one data structure with some relation between the information in order to manage, modify, and verify NC data and avoid human error. However, traditional NC data (ISO 6983) contains such kind of technical information implicitly. In this research, technical information is extracted from NC code, and the extracted technical information is transformed into a next-generation CNC control language (ISO14649) which contains the technical information, and the ISO 14649 data are stored in XML.

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This paper deals with a real-time scheduling system of HMS (Holonic Manufacturing System). Rule-based scheduling methods have been proposed and applied to the real-time production scheduling problems of the HMS in the previous report. However, there are still remaining problems from the viewpoint for the improvement of the objective functions of the individual holons. The real-time scheduling method using effectiveness values is proposed in this research, in order to improve the objective functions of the individual holons. The simulation based procedure is also implemented for the individual holons to estimate the future status of HMS and to determine the effectiveness values, aiming at improving the evaluation of the effectiveness values. Some case studies of the real-time scheduling method are carried out to verify the effectiveness of the proposed methods.

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Unscheduled disruptions often occur in the actual manufacturing systems. A systematic scheduling method is therefore required to modify and improve the initial production schedule in order to cope with the unexpected disturbances. The previous researches proposed the Genetic Algorithm based reactive scheduling method that improves the initial production schedule without interrupting the manufacturing processes. This research proposes a new crossover method based on the dominance of gene in order to modify the production schedule faster than the previous method.

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A new form of turn-milling for achieving high levels of efficiency that cannot be obtained in conventional turning has been devised. This is a technique in which the machining is performed while rotating both the tool and the workpiece, and it was shown empirically that it could be applied successfully to difficult-to-cut alloy steel under completely dry conditions. Since this is a very environmentally friendly technique that also enables the machining of alloy steels without normalizing, it can be expected to have positive effects across the whole production field including reductions in the numbers of processes and man hours required.

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This paper describes a new grinding system that incorporates a measurement unit to enable autonomous high-precision grinding control. The valve seat diameter, which is the dimension of intersection of two cones with a small angular difference, is difficult to be produced at high accuracy with any of conventional technologies. We developed the new grinding system contains the grinding unit that can process two different cones without unloading the workpiece, the seat diameter measurement unit utilizing an image processing system, and a different control algorithm for each fluctuation factor in grinding. All these features have realized the new grinding system that has three times as high precision as that of conventional systems.

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Vibration assisted machining can improve finished surface quality of hard materials and reduce tool wear. In previous researches a prototype milling machine was developed to investigate the feasibility of vibration assisted milling process. In this research, a circular vibration milling device was developed and its performance was investigated. The device is used to vibrate a cutting tool along a circular locus about its axis, in addition to tool rotation motion. The device can be attached to a normal machining center to perform circular vibration milling. Experimental results show that by using the attachment, the finished surface quality has been improved and cutting energy has been reduced compared with conventional milling process.

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A water drive spindle for diamond turning machines is proposed. The spindle uses water flow for driving the rotor by a water drive motor, for supporting the rotor by water hydrostatic pressure bearings, as well as for coolant. As water is not only incompressible and clean but also low viscosity fluid, it is considered that a high-speed and precise rotational motion will be possible in the clean environments for the precision machining. The present paper reports a structure of the spindle as well as the operational principle of the spindle. In the present paper, theoretical equations used for designing the spindle is derived. The characteristics of the spindle are studied theoretically and experimentally. A result of the diamond turning test using the developed water drive spindle is also presented.

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In order to develop linear guides which can cope with high-speed cutting of difficult-to-cut materials, the authors proposed a new hybrid-type linear guide that unites the merits of rolling guides and those of slide guides. The frictional characteristics of a hybrid-type linear guide model have been examined in the sliding velocity range from 1 to 6000mm/min and compared with those of a linear slide guide model. In both models, the sliding or rolling surfaces with a hardness of about 61 HRC were mirror finished by lapping. Results showed that in the hybrid-type linear guide selecting an appropriate clearance between the sliding surfaces may result in a constant and lower friction coefficient over a wide sliding velocity range.

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The Electro-rheological Gel (ERG) is a new functional material which shows the wide range of shear stress variation in response to the applied electric field. To apply the electric field to the ERG, it is necessary to sandwich the ERG between a pair of plane-parallel electrodes. However, it is not convenient for the practical use to wire the both of electrodes for high voltage supply. In this study, the one-sided structured electrodes are proposed in order to simplify the structure of the wiring. Moreover, the ERG on one-sided electrodes is applied to a clutch as a torque transfer device. The ERG clutch shows excellent performances in static and dynamic characteristics of torque transfer.

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Recently, the advance of numerical controller's technology has improved contouring accuracy of NC machine tools. However, conventional numerical controller has many functions in order to deal with the mechanical problem such as frictions, plays. Therefore, it is difficult to adjust the parameters of numerical controller perfectly. In this report, the difficulty of stick motion compensation is shown as an example of the complication of tuning operations.

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This paper describes a monitoring method of the cutting forces for end milling process by using displacement sensors. Four eddy-current displacement sensors are installed on the spindle housing of a machining center so that they can detect the radial motion of the rotating spindle. Thermocouples are also attached to the spindle structure, and the stability of the displacement sensing is examined. The change in spindle stiffness due to the spindle temperature and the speed is investigated as well. Finally, monitoring results of small and medium scale cutting forces in end milling operations are shown as a case study.

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Our goal is develop compact machine without sensors for inspecting parts and assembly actions. Through observing the actions by CCD camera, we studied Identification of assemble action, Adjustment support and Maintenance support. As a result, we achieved the 1/2 size of the conventional machine by removing sensors such as Proximity Sensor, Photoelectric Sensor, Auto Switch and wires.

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In recent years, desktop machine tools or multi-functional machine tools have attracted attention for cell manufacturing system. In this study, we attempt to develop the multi-functional mini machine tools with a laser heat treatment function. In the present paper, we made a prototype mini machine tool with a table drive stroke of 50mm, for the multi-functional mini machine tools. First, we evaluated the motion accuracy, the power consumption and the heat deformation of the prototype mini machine tool. Second we examined a laser source to perform the heat treatment of small mechanical parts on the machine tool table. As a result, the prototype mini machine tool was found to be effective integrating manufacturing processes on the desktop table.

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In this paper a multi-function high precision tabletop CNC machine for making micro parts is developed. All the needed machining processes can be carried out on the same machine without unloading, reloading and readjusting the workpiece for subsequent processes. Currently the functions of micro high speed milling, micro-EDM, micro wire-EDM, and micro on-line measurement have been accomplished and tested. A dual-spindle is designed for micro CNC milling, microelectrode fabrication and micro-EDM. A novel mechanism that allows versatile cutting by a 20μm diameter wire is designed for micro wire-EDM. Various micro parts and high aspect ratio microstructure are successfully fabricated. Furthermore, based on the "short-circuit principle" an on-line micro part measuring system is developed and implemented.

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Dry drilling of composite/metallic stacks for aircraft components is extremely difficult to keep sufficient hole quality and efficiency of drilling process. Problems of the dry drilling of the stacks are chip ejection, chip formation and high temperature especially for titanium alloy. To clear these problems, low-frequency vibration (10-50Hz) drilling is proposed in this study. Controlled vibration was given in drill axis direction. The relationship between vibration conditions, such as vibration amplitude, frequency and drill feed rate, and chip formation and drilling temperature were investigated. As a result, low-frequency vibration drilling can control chip formation to reduce chip jamming and reduce drilling temperature. The temperature at cap burr decreased by 300 degrees or more when low-frequency vibration was applied compared with the conventional drilling.

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The cutting performance of CBN tools-CBN-rich type and ordinary one-for high-speed end milling of hardened steel is investigated. The availability of TiAlN-coated carbide tools in low-speed hardmilling is also examined. In dry cutting of hardened carbon steel with the ordinary CBN tool, the cutting tool temperature θ_α rises rapidly with the increase of cutting speed v, and θ_α reaches approximately 850℃ at v=600m/min. In the case of the CBN-rich tool, the cutting temperature decreases by 50℃ or more because of high thermal conductivity. The hardness of workpiece has great influence on the cutting temperature. The TiAlN-coated carbide tool is sufficiently applicable to low-speed hardmilling.

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For materials having a hardness of 60 HRC or more, continuous cutting is possible with CBN tools and ceramic tools in conventional single-point cutting processes. However, in interrupted cutting of the spline outer diameter of transmission parts, there is the problem that tool life is shortened by the continuous impulse force acting on the tool cutting edge. To avoid that problem, we applied an oblique cutting method in interrupted cutting, and investigated the effect on tool life. The results showed that tool life was substantially extended compared with conventional single-point cutting, and that surface roughness was also reduced in comparison with conventional grinding processes.

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It is often reported that machining of 12%Cr steel could be difficult and optimum setting of cutting conditions, such as cutting speed, feed and depth of cut, is critical for its industrial application. 3%Co-12%Cr heat-resistant stainless steel is one of the 12%Cr steels used for critical parts in ultra super critical power plant. The main objective of this study is to explore the machinability of 3%Co-12%Cr in milling operations. The effects of tool geometry, cutting speed, feed on surface finish and tool life will be investigated with experiments.

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