Since its founding, Toyota has always made efforts to contribute to society through its expertise in producing things. Our biggest mission, I believe, is to enrich people's life by offering products in the form of motor vehicles. Focusing on our manufacturing and production engineering, I will introduce you several topics which Toyota has been tackling with persistent efforts, and our challenges in "Mono-zukuri", or in other words, providing reliable and value-added products.

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This paper studies world's trends in the machine tool industry. The past and latest machine tool technologies are reviewed. The future technological development in machine tools is also reviewed.

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The bottleneck in introducing successful new products quickly to market is moving from factory floor manufacturing to the product design process and interfaces between designers, manufacturers and users. 'Quality', for products that contact people, has moved beyond functionality and usability to satisfying people's subjective and emotional lifestyle needs. Affective (kansei) engineering design offers approaches that can be used to bring the emotional responses of consumers into the design process. In parallel, mass customisation promises the delivery of mass-produced bespoke products to individual users. Together, affective engineering and mass customisation are having a dramatic impact on the ways in which designers, engineers and manufacturers interact with each other. The challenge for leading edge manufacture is to create new product opportunities through integration of and new developments in technology, systems and design.

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Titanium alloys have been widely used in the aerospace, biomedical and automotive industries because of their good strength-to-weight ratio and superior corrosion resistance. However, it is very difficult to machine them due to their poor machinability, which has led many large companies to invest much in developing techniques to minimize machining cost. During machining of titanium alloys, their poor thermal conductivity results in the higher temperature closer to the cutting edge, and there exists strong affinity between the tool and workpiece material. When machining titanium alloys with the conventional tools, the wear rate progresses rapidly, and the cutting speed is generally difficult to be over 60m/min. Other types of tool materials, including ceramic, diamond, and cubic boron nitride (CBN), are highly reactive with titanium alloys at higher temperature, and consequently they are not effective to be used in HSM of titanium alloys. The binder-less CBN (BCBN) tools, which neither have any binder nor a sintering agent or a catalyst, have a remarkably longer tool life than conventional CBN inserts under all cutting conditions (up to 400m/min). The BCBN appears to become a new cutting tool material for HSM of titanium alloys both economically and functionally. In order to get deeper understanding of HSM of titanium alloys, the generation of mathematical models is essential. Therefore, analytical models are needed to be established to predict the machining parameters for HSM of titanium alloys. This paper aims to give an overview of recent developments in machining and HSM of titanium alloys, geometrical modeling of HSM and cutting force models for HSM of titanium alloys.

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A sequence control has been adopted for many years. But, as the circuit design of the sequence control depends on the experience of production engineers, it is insufficient to systematize the circuit design of a sequence control. The paper researches the creation system which automatically generates the perfect network figure (PNF). In order to generate the PNF, the paper proposes the methods of generating two databases from time chart. These two databases are called as the operation database and the subordinate database. In order to ascertain the goodness of the developed method, it was applied to the self-maintenance circuit.

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We deal with finishing the curved surfaces in hardened steels (JIS: SKD11, etc.) with (Al,Ti) N-coated ball end-milling. We used two kinds of cutter locations, scanning line cutting and contour line cutting, for finishing the curved surface of hardened steel. We examined the work surface roughness and tool wear. In scanning line machining, an irregular luster (striped pattern) peculiar to the machining work surface was caused. We also proposed a new method to estimate possible causes of the peculiar striped pattern which could be judged only from observation of the machined surface using Makyoh-topographic images.

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The purpose of this paper is to show a method of a performance design using statistical tolerance indices. Firstly, the sum of statistical tolerance of parts is studied. Then a decision method of statistical tolerance indices is proposed, and the proposed method is demonstrated in case study. Simultaneously, the proper condition for performance improvement using statistical tolerance index C_<pm> is shown.

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In this study a commercial inkjet printer was modified to study the resolution of fluid dot placement required to fabricate 3D multi-material patterns layer by layer. A JAVA based computer program was developed to convert stereolithography (STL) data layer by layer, control the ink cartridges individually and print ink with customized fluid dot placement arrangements. The study found out that complement printing between nozzles which is 30μm in diameter and 144μm apart is essential to achieve a fully dense 3D pattern. When printed with 36μm printing spacing vertically, a layer thickness of 1.30μm is achievable and when printing layer by layer, the thickness increases almost at a linear rate.

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The study deals with a development of a forging type rapid prototyping system on the basis of CAD data. In order to automate a metal hammering working that has been operated by human handwork conventionally, an industrial robot having high degree of freedom is adopted. A servo-hammering unit is designed to perform hammering operation imitating that of a skilled worker and it applies impulsive load to the workpiece. A CAM system suitable for metal hammering working is developed. Especially, the posture of the hammer is considered under deforming in progress. From the experimental result, the system can deform the workpieces (aluminum plate) on the basis of CAD data and it having an ability to perform the automatic metal hammering on the basis of CAD data as a rapid prototyping system is found.

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Solid modelers enable engineers to design 3D objects including free-form surfaces, and solid models can be used for many systems such as CAM and CAE. However, solid modelers are generally too expensive comparing to 2D CAD systems, and it is difficult and time consuming to create the solid models of products consisting of a great many parts. In this case, the products can be expressed simply in 2D CAD systems by using simplified expressions such as omissions and sectional views. In this paper, a method is proposed that can convert 2D drawings of structures including omissions and sectional views into 3D models. The properties of simplified expressions are formulated as an algorithm in the method.

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The DBB (Double Ball Bar) method is able to analyze motion errors of a machine tool in the un-loaded condition. However, the method cannot be applied in the loaded condition. Researches on machining error analyses proposed so far have successfully obtained precise estimation results, but applications of such analyses are extremely limited. In order to realize high accuracy machining, it is necessary to identify the factors of machining errors in the loaded condition and eliminate these errors from machined parts. The objective of this study is to develop a system to analyze and identify the error factors of machining by comparing the measurement data of a machined part with CAD data. The usefulness of the developed system was verified through tests.

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The objective of this study is to develop a system which automatically constructs a database in order to generate high quality NC program realizing optimum machining processes. The database is constructed by relating cutting features to machining states and cutting conditions in a hierarchical structure. The relationships are derived by analyzing a NC program and machine tool operations executed by a skilled operator. The developed system is composed of "Machine tool operation identification system", "Cutting method recognition system", "Cutting feature recognition system", and "Automatic database construction system". A cutting feature represents a basic and characteristic form to be removed in a continuous cutting process, and is defined as a set of ordered cutting patterns with continuous cutting tool location data. A cutting pattern indicates a cutting method and a geometric status between a cutting tool and a workpiece, and a cutting pattern with cutting conditions means the geometric status and cutting methods.

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The purpose of this study is to propose a magnetic technique for damping characteristic improvement of structures packed with balls. First, the damping characteristics of structures packed with magnetic balls are experimentally investigated. The effect of the packing ratio on damping characteristics is then examined. The damping characteristics of these structures are affected by the magnetic force among the packed balls themselves, and between the packed balls and the structure. Second, the structures are packed with non-magnetic steel balls and a permanent magnet source is put outside the structures. Next, we examine the effect of the distance between the permanent magnetic source and structure, that is the intensity of the magnetic force, on the damping characteristics. In both types of structures, it is considered that the effective damping capacity improvement is achieved by the magnetic force among packed balls and between packed balls and structures.

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Many multi-task machines have been developed recently because of demands for reduction of the number of machining processes. Therefore, in this study, the new measuring method of thermal deviations with the linear axis motion is devised for a multi-task machine. This method is possible to do the same measurement as the method standardized in ISO230-3. Using this measurement system, thermal deviations with the reciprocating mo tion of the carriage are measured on the actual multi-task machine with the general structure. From the results, we obtain following conclusions. The method we proposed here has validity. The estimation of the thermal deformation mode is possible with synthetic evaluation of the measurement result from this measuring method.

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The study has been carried out to develop and evaluate a measurement system for the cutting tools angular motion (B-axis motion) relative to the chuck spindle in a mill-turn integrated machine tool. The B-axis Measurement Device (BMD) consisting of two modules, the laser module and the CCD module have been designed and developed. The laser module is attached to the tool spindle and the CCD module is mounted at the chuck spindle. The laser module has an optical fiber laser that can rotate along the same plane as the B-axis. The CCD module has two CCD cameras, and also a mechanism to rotate in the B-axis plane. Angular encoders measure the exact rotations of the laser and CCD cameras. By projecting the laser beam onto the CCD cameras, BMD evaluates the rotational accuracy of B-axis. The study has confirmed that BMD can successfully measure the B-axis accuracy with the resolution of 10 arcsec in the developed system.

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In an attempt to reduce costs within the high quality metal mold industry there is a turn toward shortening the lead time in all aspects of manufacturing from the metal mold design to the completion of the actual metal mold manufacture. The new developed machine has a range of 6 to 9 heads allowing a variety of different curved surfaces to be processed at the same time on the same metal mold material, and shorten processing time to less than half of the conventional machines.

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The study deals with a new method to generate interference-free tool posture for 5-axis control machining using a ball end-mill. The 5-axis control machining can produce complicated shapes and parts consisting of overhanging and or sculptured surfaces such as impellers. However, high degree of freedom of 5-axis control machining center causes a fatal problem that other parts except cutting edges of the tool may interfere with other surfaces of the machining object. Therefore, it is necessary to obtain the adequate tool postures to avoid the interference during machining. The interference avoidance is generally performed by the method that cutting points are generated so as to be arranged on the surface to be machined, and then the interference-free tool posture is determined on each cutting point by the geometrical calculations. However, the method has a problem that it takes long time for calculation. To solve the problem, the study proposes a new interference avoidance method of reversing the order of the above procedure, i.e., that of determining a set of interference-free tool postures before generating cutting points. From the machining results, it is confirmed that the proposed method is available to fabricate complicated shapes since the impeller can be machined by using the method.

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This paper deals with a new evaluation method of tool posture for 5-axis control machining. The 5-axis control machining realizes high productivity, because it can fabricate workpiece surface with an arbitrary posture of cutting tools. However, it is known that generation of the NC Program for continuous 5-axis control machining without collisions is quite difficult problem. So, the efficient evaluation method is strongly required. In this paper, we propose a new evaluation method which introduces graphic hardware as fast geometric calculator. We develop a prototype system and confirm that the proposed method can attain extraordinary improvement in the evaluation time.

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The study deals with the automation of polishing process for free-form surfaces by means of an industrial robot. In general, the polishing process has been performed by handwork of skilled workers. Since the polishing environment is extremely inferior and the polishing process is time-consuming and tedious work, the automation of polishing process is strongly desired. In the study, the polishing path generation is devised to improve the surface quality. Thus, the relationship between the surface curvature of workpiece and the contact length of polishing tool is investigated by experiments, which results in the new polishing path generation method. As a result, it is found that the new polishing path generation method is effective for polishing automation by robots.

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Multi-axis machines allow manufacturing of complex geometries in a single machine set up. Because of the machines' complexity, calibration processes are usually difficult and involved. Rotary tables are widely used as key components in multi-axis machines to provide two rotational degrees of freedom. This paper presents a comprehensive scheme for rotary table calibration: measurement principle, system design and prototype building, measurement evaluation of the prototype. The factors influencing the measurement accuracy were analysed.

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A number of test methods for checking the geometric inaccuracy of the RRTTT type five-axis machining centers have been specified in ISO standards. However such procedures are relatively involved in terms of equipments and operator expertise and simpler means are thus sought. This paper presents a new calibration method to check the geometric inaccuracy of the RRTTT type machining centers which is based on the modified motion of the basic motion described by the spherical interpolation of five axes as specified in clause K6 of ISO 10791- part 6. In addition, a methodology for identifying the static deviations is proposed. This methodology consists of three steps. In the steps 1 and 2, six of ten deviations were identified by means of observation equation. The rest of the ten deviations were identified in the step 3 by means of link geometry of the machining center. The simulations are carried out to verify the proposed calibration method and the results are confirmed that the proposed method gives good results for deviations.

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These days, environment problems are getting much more attention than ever these days, and we have been working on developing dry machining technology which requires MQL or no cutting fluid includes toxic pollutant such as chlorine. In this paper, we will introduce a newly developed MQL cutting process. After evaluated cutting performance of absolute dry cutting, dry cutting with air-cooling, and MQL cutting, we chose MQL cutting which was found to be superior in terms of the main issues, lubrication and cooling. And then, we developed new MQL cutting by adopting newly developed high lubrication cutting fluid and incidental facilities to secure the same cutting tool life and cutting accuracy as those of conventional wet cutting.

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Titanium machining poses a great challenge to cutting tools, and yields serious negative influence on tool life. Thus, cooling supply strategies are widely used in its machining process. On account of this, the tool wear performance from dry cutting, flood cooling and minimum quantity lubrication (MQL) techniques is investigated. This study focuses on cutting tool life under the varied cutting conditions and cooling supply strategies so as to establish effective titanium cutting. Experimental results proved that compared with dry cutting and flood cooling, MQL aided machining can remarkably and reliably improve tool life in titanium machining.

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Series of orthogonal cutting tests of Aluminum alloys have been carried out to investigate the chip formation process and adhesion of the work material to the rake face of the cutting tool under near dry cutting conditions. Almost no adhesion of the work material was observed over a wide range of cutting speed tested when the Aluminum alloy was cut with the sintered diamond cutting tool. On the other hand, large amount of adhesion of the work material was observed at low cutting speeds, when cut with the carbide and DLC-coated tools. The amount of the adhered material is reduced with an increase in the cutting speed. The nominal coefficient of friction on the rake face increases almost in linear relation with the amount of adhesion. The chemical components of the adhered layer were analyzed by EDS and AES techniques.

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This work presents the investigation of the errors induced by cutting forces. In order to predict tool deflection, an evaluation of the stiffness of the system formed by the machine-tool, shank and toolholder, collet and tool is presented. Cutting forces induce the deflection of the system, and consequently an error appears on the machined surface. Cutting forces have been estimated using a semi-empirical approach valid for complex surfaces and a previous study of the deflection chain in the cutting process is presented too. Results show that stiffness of the slender and flexible tools is 15 times lower than that of the machine and toolholder system. But this correlation is only 57 times lower for shorter and thicker tools. The final application is the ball-end milling of complex surfaces (moulds and dies), an operation commonly performed in the finishing of moulds or forging dies, where errors of more than 70μm are not unusual.

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This paper presents originally the experimental measurement method of the machining accuracy in the ball-nosed end milling. This method makes it possible to machine in every tool orientation with the three-axis-controlled machine tool. The machined surface profile is precisely measured by the noncontact 3-dimensional measuring instrument. Several experimental results in some cutting conditions are presented. The relationship of tool orientation and machining accuracy was clarified. The adequate and inadequate tool orientation was found. In addition the reasonable tool orientation on ball-nosed end milling was discussed comparing with the experimental results and the geometric analysis of the undeformed chip thickness.

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This paper presents a mechanics model for predicting the forces of cutting aluminum-based SiC/Al_2O_3 particle reinforced MMCs. The force generation mechanism was considered to be due to three factors: (a) the chip formation force, (b) the ploughing force, and (c) the particle fracture force. The chip formation force was obtained by using the Merchant's analysis but those due to matrix ploughing deformation and particle fracture were formulated, respectively, with the aid of the slip line field theory of plasticity and the Griffith theory of fracture. A comparison of the model predictions with the experimental results published in the literature showed that the theoretical model developed has captured the major material removal/deformation mechanisms in MMCs and describes very well the experimental measurements.

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In machining of nickel based superalloys, such as Inconel 718, tool wear is a major problem. Enhanced knowledge of the tool wear mechanism and capability to predict tool wear are of great importance. The objective with this paper is to investigate if an empirical wear model can describe the flank and crater wear of uncoated cemented carbide tool in a turning operation of Inconel 718. This empirical model has been implemented in a commercial FE-code and experimental trials have been conducted in order to obtain parameters of the empirical wear model and for validation. The wear rate volume at the flank and rake face as well as the cutting edge radius was measured with white light interferometry. FE-simulations were performed to calculate the wear rate at different cutting speeds. Results and comparison between experiments and simulation are presented in the paper.

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Tool chatter vibration is known as one of most complicated processes of machining because it is very difficult to explain and predict the dynamic behavior of tool chatter in time domain by not only linear theories but also nonlinear theories proposed so far. Hence, in this paper, non linearity of the damping coefficient of cutting tool in chatter vibration was investigated experimentally using restricted contact cutaway tools and a normal tool, which have one degree of freedom in the feed direction. Change in the damping coefficient during chatter was obtained from the Lissajous' figure, which showed the trajectories of chatter vibration in a two-dimensional space of the feed force and displacement in the feed direction, on the assumption that the energy balance of chatter was in quasi-steady state. As the result, it was found that the damping coefficient increased with amplitude of vibration at the beginning of chatter. However, when the amplitude increased to a certain value, the runout of the cutting tool occurred and the damping coefficient decreased.

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In this study, experimental investigation of the effect of cutting tool rake angle during machining of AA 2011 and AA 7075 aluminium alloys was carried out. For this purpose, a previously designed and manufactured dynamometer incorporating load cells was used to measure the cutting forces during turning. This system enabled the tool holder to rotate so that the cutting tool's rake angle could be adjusted. The machining tests were conducted at six different rake angles, five different cutting speeds while feed rate and depth of cut were kept constant. During the tests, primary cutting force (F_c) and feed force (F_a) components were measured and recorded on a personal computer (PC). Theoretical cutting force values were also determined using Kienzle approach. The results showed that cutting forces decreased with increasing rake angle and increasing cutting speed for the both alloys.

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Influence of cool air on the cooling ability in grinding process has been studied. By blowing cool air through the grinding zone, heat is taken out of the grinding zone and the surface temperature of workpiece also is reduced. This is confirmed by some theoretical and experimental research. However, in order to use cool air on the grinding more effectively, the more theoretical research is necessary. In this research, we try to make clearly the influence of grinding conditions on the heat removed. We also try to make clearly the influence of cool air parameters as temperature, pressure and flow rate on the distribution of heat in grinding as well as the heat removed by cool air in order to give a optimal grinding conditions in cool air grinding. In addition, the application ability of cool air in grinding is apart of this research.

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The purpose of this paper is to obtain fundamental knowledge about various cooling modes from grinding phenomena. In cool-air grinding, we could obtain less accumulated chips on the sides and chip adhesions than those in dry grinding. Though we could observe the clear grinding grooves and the clean ground surface, the ground surface roughness in mist grinding was large. The ground surface roughness in cool-air mist grinding was nearly equal to that in cool-air grinding. The width of grinding grooves was small in cool-air mist grinding. The cleanness of ground surface in cool-air mist grinding was almost similar with that in wet grinding.

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Fullerene has some special structural, physical, and mechanical properties. The precise and efficient machining by this material to the required quality has not yet been well established. In this paper, a comparative study was conducted to investigate the special aspects in the polishing of silicon wafer using the fullerene wheel, and the diamond wheel of super fine grains. The stability of surface roughness, effects of material grains sizes on the grinding results, and microscopic analysis of grinding phenomena by both materials were also analyzed in detail. The sintering temperature of near 700℃ is suitable for manufacturing diamond wheel. The carbon beads fit to fabricate the small pores in the vitrified-bonded wheel in comparison with the polyethylene beads. The surface roughness of hardened steel is rather larger when ground by 0〜1/8μm than when ground by 0〜1/4μm of diamond grain. This is because the abrasive grains were covered with the bond. It was clarified that we can obtain the surface roughness of 5nm Ra when using fullerene in polishing of silicon wafer.

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Glass quartz, crystal quartz and single crystal silicon are plunge ground with different mesh sizes of metal-bonded diamond grinding wheels, the cutting edges of which are truncated so as to be aligned with the height of the grinding wheel working surface, and the difference in ground surface morphologies between them are investigated. It is found that ductile-mode grinding of quartz is likely to be realized by the cutting edge truncation and a SD600 grinding wheel brings about a surface morphology better than SD270 grinding wheel, even if both the grinding wheels are truncated.

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In this study, three kinds of granite were lapped and polished by loose abrasives. Different abrasives and different kinds of polishing plates were used. The material removal mechanism was investigated by tracing their morphological changes of granite surface during the successive lapping and polishing processes. The experimental results indicated that the material removal mechanism during the lapping and polishing with loose abrasives is a mechanical process and it is affected by the size of abrasive and the applied load. Smooth surface can be obtained through eliminating the pits remained by the grinding process. When the grit size was reduced to a critical value, further reduction of the grit size did not have any obvious effects on the increasing of glossiness even the polishing is prolonged. However, the material of the polishing plate may affect the glossiness.

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