Double Ball Joint was developed for the improvement of the precision of a parallel link mechanism. Double Ball Joint agreed with the function of two Ball Joint or more and those centers of gyrations were matched as it was. It is effective for the simplification of the mechanism and the simplification of the high precision and the inverse kinematics calculation, etc. It reports on the parallel link positioning stage where Double Ball Joint was used is produced and the operation experiment and the performance assessment were done.

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This study treats human body model and cellular automata for analysis of the passenger behavior for the deceleration at the time of the railway accident. At this case, the deceleration obtained from simulation of the railroad carriage model is used for simulation suppose to collision to the rigid body wall. Consequently, it was shown that injury to the passenger was able to be reduced by the parameter of the partition and the floor when accident was occured.

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V3-P stand for the Value up Innovation for product process program in NISSAN, which is aimed for the most efficient vehicle development , shortening of development term and to spend the more time for engineer's creative job. We have the three main scheme, "Know how CAD", "Digital test (CAE)" and "Digital prototype" to achieve V3-P. Know how CAD is the system which achieve storage and reuse the manufacturing know how include standard process and structure. Inexperienced engineer can receive standard process and structure same as skillful engineer from it. Know how CAD is utilized not also in Japan but also in whole the world and makes most efficient and high quality for vehicle development in V-3P.

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We developed a configurater that searches an experienced part what accepts constraints, and replaces from a part what doesn't accept constraints to the searched part. The experienced part is more reliable than a new part. But it is heavy process to search replaceable part from large quantities of experienced parts. So the configurater we developed is based on parameter network model for searching parts what accept a constraint quickly. Parameter network model expresses relationship between design parameters, and constraint of parameters. Its capacity is less than CAD model's capacity so the configurater based on Parameter network model decreases search time.

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This paper presents a concept of stereo viewer system through interaction with virtual objects. First, this paper overviews a typical technique to implement an augmented reality environment. Then, this paper proposes a stereo viewer approach using an interaction with virtual objects. This approach is implemented with a prototype system composed of a rear-projection display system, a CCD camera and an AR marker cap. Two examples of interaction are presented using a motorcycle model and a house model. Considering the results of experiments in these two examples, this paper discusses the feasibility of the proposed approach.

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The goal of this study is development of "Miniature Space Experience System" which makes an observer feel a sense of standing in a miniature space. For this purpose, we focus on a body shadow to enhance information of his position and change a sense of body scale. Developed system consists of a gantry type camera device which moves in a miniature space and a miniature shadow projection device. And as a result of some experiments utilizing this system, the effectiveness of proposed method was confirmed.

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As an Embodiment method of Virtual Tool represented by computer graphics, we have developed Extendable Virtual Tool focused on rhythm. The purpose of this study is to measure interaction between Extendable Virtual Tool and body movement. So, a novel system measuring external force to Virtual Tool and myoelectric potential was developed. And an effectiveness of this system was confirmed by results of experiments.

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The aim of this study is to realize the pair waking between remote locations. In this system, a person who is indoors enters a remote outdoor space through his own robot avatar, and he can walks with a person who is in the outdoor space. In order to create a feeling of connection between indoor person and outdoor person in this system, the robot avatar and outdoor person were connected through a string, and we developed a string interface that recreated this string's movement in the indoor space. Furthermore, we developed video presentation system that shows the situation of outdoor space in the indoor space. As a result, we realized the pair waking between remote locations with connecting the indoor person and outdoor person through the string interface.

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This paper proposes the novel method for supporting the communication of "Ba" on site by using aerial drawing system combined with the physical expression activities. In this method, in order to develop a relationship between two users and extract the bodily expressions together, this system connects the band-shaped 3DCG between each of hands and generates the trajectory as a surface-shaped CG during dancing jointly. Moreover, after the bodily expressions the solid object representing the relationship is made by overlapping all surfaces. Then the 3D objects are projected on a translucent cloth with which the participant was covered, and consequently we developed the method that the object not only was demonstrated the relations with the object floating in the air, for the participant under the cloth, but also made their sense like being wrapped in the expression. At last, we applied these systems to some workshops which general participants take part and confirmed the effectiveness to the possibility of extract a new expression of the participants.

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When a Nd : YAG laser, the wavelength of which is permeable for diamond, is focused on the surface of a diamond sample, a layer of surface material is ablated. Therefore, diamond can be cut by repetitive irradiation. In this study, the processing mechanism of ablation for a single crystal diamond was examined using a heat conduction analysis, considering laser absorption at the surface or the temperature dependence of absorption coefficient. When the laser beam is absorbed at the surface layer, the surface layer is ablated during an early period in the laser pulse. Once the absorption surface layer is ablated, the laser beam penetrates the base material and ablation stops. On the other hand, if we assume single crystal diamond has the temperature dependence of absorption coefficient which is about equal to that of CVD diamond, the temperature rise is not enough to ablate the material. However, it became clear that the diamond is ablated deeply when we consider both absorption at the surface layer and the temperature dependence of the absorption coefficient. It can be considered that the surface is transformed to graphite and becomes the absorption layer during the repetitive irradiation. It is estimated that the phase change to graphite is very small and its volume fraction is about one percent.

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Generally, wet cutting which supplies a lot of cutting fluid is adopted as precision cutting of the aluminum alloy used abundantly at the parts for automobile. When near-dry cutting is used as this processing, it is easy to grow up a built-up edge, and guarantee of dimensional tolerance or surface roughness is difficult. So, in this study, it aimed at an elucidation of the generating mechanism of a built-up edge and development of the reduction method for precision cutting of an aluminum alloy. This pepper examined the basic examination result of the cutting performance, such as a cutting speed, cutting temperature, a coefficient of friction of a rake face, and surface roughness when using MQL (Minimum Qantity Lubrication) cutting of the A6061 (T6) material with a cemented carbide.

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The micro-channel chip (micro total analysis system) attracts attention in the medical field. Generally, the photo lithography technology used in a semiconductor manufacture process is used as the manufacture method of a micro-channel chip die. However, there are many manufacturing processes like fabrication of a mask, the photo-resist application to a substrate, expensive facility of a clean room etc. So, this study examined how to form a fine groove by cutting with a micro end mill. This report examined experimentally the processing conditions which should be developed. As a result, the cutting edge roundness of a micro end mill and the cutting performance, such as burr generating, were clarified.

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Rapid prototyping apparatuses are widely used to create 3-dimensional models for industrial and medical applications. A stereolithography in which photosensitive resin is cured by laminating thin layers one by one has an issue of taking long time to fabricate a 3D model. In this research, a new stereolithography which uses multi laser beam to fabricate a 3D model is proposed. In this method, concentrating multi beams enhances the beam intensity to cure photopolymer at the beam-crossing point. This article describes the capability of this method. The property of the photopotymer was examined for realizing this method, and a fine columnar rod was successfully fabricated by scanning two beams at a position of beam-crossing.

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The powder forming process is advantageous for near net shape manufacturing when compared with metal casting and metal forming processes. However, because of an increasing demand for formed parts with more complex shapes in recent years, some material removal processes are necessary for formed parts, including sintered mechanical parts produced by powder forming, despite its superiority in near net shape manufacturing. As such, machinability is also becoming an important factor for powder forming. The metal removal process used for powder metallurgy parts is usually applied to sintered compacts. However, a removal process for the powder compact prior to sintering (referred to as "green compacts"), which is known as green machining, has been attracting attention lately. Since the mechanical strengths of green compacts are markedly lower than that of sintered parts, the cutting force required for green compacts is much lower than that required for normal sintered parts even in difficult-to-cut-materials. Furthermore, because the chips from green machining are considerably smaller than those from sintered parts, the removal of chips from the holes of the drilled parts is much easier in case of green compacts. This provides a strong advantage when producing parts containing holes, such as hydraulic components, which must be totally free of chips. On the other hand, the relatively low mechanical strengths of green compacts, compared with sintered compacts, are disadvantageous in the chucking to cutting machine of the green parts, because they are harder to clamp in place (chuck). In order for green machining to gain full acceptance, it is necessary that sintered parts produced by this method have the same mechanical strength as sintered parts produced by conventional sinter machining. In the present study, we compared the mechanical strength of a cylindrical compact formed from ferrous powder, which was drilled and then sintered, with the mechanical strength of a part that was sintered and then drilled to produce the same shape. The mechanical strength was evaluated according to the radial crushing strength test (JIS-Z-2507). The result was as follows : (1) The mechanical strength of the test piece produced by green machining and then sintered was no different from that of the test piece produced by machining after sintering (2) The torque required during the drilling process of green machining was approximately 30% of what was required for drilling after sintering, and the thrust in the same comparison was approximately 40%.

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Cress is one of the chief products in KUMANO. However, the kneading process of cress by hand requires very hard work, and this causes the low-efficiency of this product. So, we are going to develop the auto-kneading machine for cress so as to increase the productivity. At first, we set the designing condition to get the high quality kneaded cress. Productivity of machine itself is enough as same as hand work, because the problem is decrease of manpower. Secondly, to get the high quality kneaded cress, machine must be able to knead with various motions. So, we employed an intelligent servo motor system called 'Cool Muscle'. Machine is constructed with conveyer, 6-roller, and pantograph unit, so as to get the analytic data easily. This machine is the prototype to get the most suitable mechanical kneading motion. After we get the suitable kneading motion, as next step, we will develop the commercial machine with low cost. Unfortunately, summer season is the season-off of Cress, so we can't perform the experiment. So, this paper explains the designing result of prototype of kneading machine.

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This paper proposes a set of machining tests for a five-axis machine tool to identify its kinematic errors, one of its most fundamental error sources. In each machining pattern, a simple side-cutting along a straight path using a straight end mill is performed. The relationship between geometric errors of the finished workpiece and the machine's kinematic errors is formulated based on the kinematic model of a five-axis machine. The identification of kinematic errors from geometric errors of finished workpiece is experimentally demonstrated on a commercial five-axis machining center, and the estimates are compared to those estimated based on ball bar measurements.

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In this research, machining experiments of helical gears by using a general-purpose 5-axis machining center with ball end mills under many kinds of cutting conditions were carried out Machining errors of involute profile and helical tooth trace of the gears were measured by using a CNC gear tester. The errors were analyzed and corrected by adjusting pressure angle and helical angle of the gears in their 3D-CAD modeling. The proposed error correction method is proved effectively.

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Numerous researches have been reported in the literature on the cutting force control in end milling processes. There have been, however, very few practical applications actually employed in commercial products. The paper presents a simple, practically feasible and effective scheme to regulate the tool life through a long-term control of cutting force. Cutting force is monitored only at tool path check points, set typically at intervals of several dozen meters. Feedback control focuses only on a long-term point-to-point regulation of cutting force, targeting tool life providing cutting for the given desired distance. The effectiveness of the present approach is experimentally investigated by an application example to contour-parallel cutting of hardened steel.

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To achieve high speed rotary cutting of high hardness super alloys, influences of tool peripheral speed, tool diameter, and tool inclination angle on thermal behavior and adhesions are investigated. Rotary cutting tests of Inconel718 of HRC45, are carried out using coated carbide tools at up to 500 m/min of surface speed. By employing a larger diameter tool and selecting an appropriate tool peripheral speed so as to reduce the tool-workpiece contact time and frictions, tool temperatures and failures are suppressed. Adhesions are also reduced utilizing the tool inclination angle control.

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Authors have been developed a novel double-sided polishing machine with high efficiency for IT devices. This machine consists of upper, lower platens and a pallet for work pieces. It has a new mechanism for high efficiency using circular moving each other parts. This machine has two major features. Firstly, the production efficiency obtained three times and more than the similar polishing area machine. Because this machine has no rotating center-shaft, the polishing area becomes larger than conventional polishing machine. Secondly, the high polishing rate is obtained using the water based with CeO_2 abrasives under AC. electric field.

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Because machining fluid such as cutting oil and grinding fluid contained several chemicals (oil, extreme pressure agent, anti rust agent, surface active agent etc.), enormous disposal cost and environmental load is occurred In this investigation, electric rust preventive machining method which uses only water for machining fluid is developed In this paper, to achieve more effective rust prevention, the optimized rust prevention current was verified. As a result, rust prevention of electro-magnetic chuck is achieved by very low power consumption of 0.028W (0.009Ax 3.1 V, 1 hour). In addition, supporting electrode (anode) which realizes effective rust prevention in gap between workpiece and electro-magnetic chuck is developed. Moreover, rust preventive effect is evaluated under using supporting electrode. Rust prevention of electro-magnetic chuck and workpiece is confirmed in 0.1A(15V : 1.5 W, one workpiece, lhour), 0.2A (20V : 4W, twoworkpieces, Ihour).

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Various advantages exist if it is possible to miniaturize machine tools to fit processing object. However, simply miniaturization of a machine tool ordinary decreases the rigidity of the machine tool, and it cause decreasing of the accuracy and performance. For a miniaturization of machine tools that keep their rigidity, we proposed a new structure of small milling machine that have a work space in the shell structure. Next, the difference from usual machine tools in design was considered. Moreover, a FEM analysis was executed for spherical shell models with proposed structure, and it was shown that making a proper thickness distribution is important to enhance rigidity.

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Spindle vibration of machine tools causes tool wear prematurely and decreases machining accuracy. The vibration changes depending on the used tooling and the rotation speed during various machining operations. In particular, even small unbalance mass of the spindle makes large whirl in high speed machining. However, real-time balancing for a machine tool spindle has not yet been realized successfully including the influence of the used tooling. In this study, a real-time balancing mechanism using magnetic fluid is proposed. The magnetic fluid is enclosed inside the spindle, and the distribution of circumferential mass is controlled to compensate for unbalance mass in real-time. A machine tool spindle equipped with the proposed real-time balancing mechanism is designed and developed. It is experimentally confirmed that unbalance response of the spindle is significantly improved. The experimental results proved the feasibility of the proposed real-time balancing mechanism for a machine tool spindle.

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This study presents a simple method to compensate the thermal deformation by measuring temperatures at only a few points on a CNC lathe. Approximate functions are derived for the compensation from the thermal deformations of a head stock and a ball screw, which can be considered as the main factor to cause the thermal deformation of a lathe. The approximate formula of the thermal deformation about the headstock is derived as a function of the temperatures measured at a few points and the rotational speed of the main spindle. Furthermore, the approximate formula of the thermal deformation of the ball screw is likewise derived as a function of the temperatures of the ball nut. By using the estimation value of the thermal deformation obtained from both the approximation functions, the study confirms the work error is well compensated.

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Compared to a conventional serial kinematic machine tool, a parallel kinematic machine tool has advantages for high speed and multi-degrees of freedom positioning. However, it is difficult to achieve high speed cutting because of its relatively complex structures. In order to achieve high speed cutting on a parallel kinematic machine tool, it is important to optimize the tool path and the workpiece position. In this study, the strut motion controlling a spindle unit is simulated while cutting. And external forces, which are gravity, friction and inertia forces, acting each strut are estimated by solving the kinematic model. The tool posture, the feed direction of ball-end milling and the workpiece setup position are evaluated based on the estimated external forces. It is confirmed that the variation of servo motor load can be reduced during a cutting operation on a parallel kinematic machine tool.

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Cooling pipes in molds are generally machined by drills. Such cooling pipes are inefficient due to their simple shapes. To overcome the limitation of their shape, our research group has developed a new method to machine holes whose cross sections change along their center axes, which is called cross section's changing holes in the study. The machining method has the ability of making cooling pipes which are build in molds have various-shaped fins on their inside wall. Accordingly, it is expected that such cooling pipes have higher performance than that of conventional ones qualitatively. However, not only the quantitative performance difference of the cooling pipes before and after the improvement but even the basic performance of the improved cooling pipes is not clarified. To solve the problem, the study quantitatively analyzes one of their basic performances, the ability of taking away quantity of heat per a certain time, of the improved cooling pipes, and compares it with that of usual cooling pipes. From the results of the analysis, it is found that the performance of the improved cooling pipes is about twice higher than that of usual cooling pipes.

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The objective of this study is to clarify a mechanism of the surface formation in ultraprecision cutting of high Si aluminum alloys using a single point diamond tool. For this purpose, ultraprecision cutting experiments of AC9A aluminum alloy have been conducted by means of the fly-cutting method using a single crystal diamond tool with a round nose. When the feed rate is smaller than a critical feed rate under a constant cutting speed and a constant depth of cut, the ductile mode cutting can be performed on Si particles.

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Turning of single crystal silicon on a (100) surface was carried out using straight-nosed single crystal diamond cutting tool with a rake angle of -20°, and a side cutting edge angle of 5°. This side cutting edge angle enables the turning of silicon in high depth of cut. The surface roughness of the work piece was about 20nm PV, when the feed speed of the tool was 0.3mm/min and 0.6mm/min, depth of cut was 10μm, revolution speed of the work piece was 3000min^<-1>. During the turning of silicon, cutting force was measured by using cutting force dynamometer, and relation between the cutting force and tool feed speed was also investigated.

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Two-dimensional vertical ultrasonically assisted grinding technique is proposed for the machining of monocrystal silicon using the ultrasonic vibrator produced by bonding a PZT device on a metal elastic body as the elliptic ultrasonic vibration is generated by the simultaneous creation of the longitudinal and bending vibration of the vibrator. The obtained experimental results about the grinding forces and surface roughness on the different experiment conditions show that the grinding forces and surface roughness decrease and the surface quality is improved compared with those in the conventional grinding.

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The aspherical lenses are used for various optical instruments. It is thought that the ultra precision grinding is suitable for manufacturing these lenses and the molds because of the viewpoint on the material and accuracy. But it is necessary to form the grinding wheel in the arc section shape in high accuracy to grind the curved surface in high accuracy. We examined the forming superabrasive wheel in high accuracy on grinding machine in three methods. After that, cemented carbide often used for the mold are ground in best method of them. As a result, the processing accuracy of profile accuracy 0.2μm and surface roughness 10nm were obtained.

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Recently, AV equipments are required high quality image. In case of PDF, the micro wiring on display panel has enable high-definition image. In this paper, it tried to form the micro silver wiring by laser direct irradiation. As the result, we succeeded forming micro silver wiring, width : 48μm and electrical resistivity : 2.5×10^<-6>Ω・cm.

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Recently, the demand to the diffractive optical elements is increasing with the developments in the micro fabrication technology. In this research, we created the diffractive optical elements with the use of the laser direct write lithography system that has the feature of high-resolution drawing, high-speed drawing, and a high accuracy positioning system. Although it is difficult to draw to a large-sized substrate with electron-beam lithography system, since the laser direct lithography system makes it possible, production of the large diffractive optical elements is expected. Furthermore, 2 and 4 levels phase-type diffraction optical elements were produced by dry etching processing to the substrate, and comparison of the diffraction efficiency of the amplitude-type diffractive optical element and the phase-type diffractive optical element. And the hologram was produced based on the diffraction efficiency of compared the diffractive optical elements.

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This research developed a new type of magnetic finishing tool, "Ultra-precision Magnetic Abrasive Slurry, for a magnetic field assisted internal finishing process in order to obtain an ultra-precision surface. This ultra-precision magnetic abrasive slurry is made to mix simply the super-minute abrasive grains, minute globular iron particles, and oily grinding liquid. When the internal finishing was executed, the stir phenomenon of the magnetic abrasive slurry is caused, at the same time, super-minute abrasive grains and minute iron particles were uniformly distributed to the magnetic abrasive slurry. It was confirmed that a smooth mirror internal finishing for a SUSS 04 stainless steel tube is able to be achieved, by using this magnetic abrasive slurry.

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This study aims to develop an ultrasonically assisted grinding technology for internal precision machining of small holes such as those formed in a fuel injector for an automotive engine. In the previous work, an experimental apparatus for internal grinding was established by installing an ultrasonic spindle onto a commercial internal grinder. In this work, a metal bonded diamond wheel is employed in the ultrasonically assisted internal grinding of small holes due to its excellent abrasion resistance. This report describes the performance of this kind of wheel in actual grinding experiments in details.

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In our previous study, a new centerless grinding method using surface grinder was proposed. This paper studies the workpiece rotation motion during grinding process. The vibration characteristics of ultrasonic shoe were investigated at first to clarify the effect of applied voltage on the motion of shoe end-face. Then, the workpiece rotation test was carried out to measure the motion on the shoe end-face and predict the rotational speed of workpiece. Finally, the actual grinding operations were performed with and without a friction plate on the end-face of shoe, respectively. The results indicated that the workpiece rotational speed can be controlled exactly by the shoe ultrasonic vibration and a higher workpiece rotational speed results with a better roundness.

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Silicon Carbide (SiC) have attracted increasing attention as one of materials for next-generation power devices. However, there are difficulties in high-efficient and ultra-precision grinding of SiC materials due to hard and brittle characteristics. We investigated appropriate surface grinding condition of 4H-SiC wafers by using ultra-fine diamond wheels. In this paper, we realized some effects of the kind of grinding wheel and wheel speed by measuring grinding force, flatness and roughness on work. By using vitrified bonded diamond wheel SD2000V for rough grinding and resinoid bonded diamond wheel SD5000B for finish grinding, the accuracy of work surface has reached PV = 0.56μm in flatness and Rz = 20.2 nm in roughness.

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A tool-swinging cutting method was proposed to reduce the wear of round-nosed diamond tools in ductile cutting of reaction-bonded SiC (RB-SiC). In this method, the geometrical center of the cutting edge was adjusted to be in coincidence with the rotation center of the B-axis table, and thus the cutting point could be changed along the cutting edge by swinging the tool about the B-axis. A surface finish of 46 nm Rz and 4 nm Ra was obtained. The width of the flank wear land of the tool was remarkably smaller than that generated by the conventional cutting method.

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Diamond-ground silicon wafers were irradiated by a high-frequency nanosecond pulsed Nd : YAG laser. The resulting specimens were characterized using a white-light interferometer, a micro-Raman spectroscope and a transmission electron microscope. The results indicate that around the laser beam center where the laser energy density is sufficiently high, the grinding-induced amorphous silicon was completely transformed into the single-crystal structure. The optimum conditions for one- and two-dimensional overlapping irradiation were experimentally obtained for processing large-diameter silicon wafers. It was found that the energy density level required for completely removing the dislocations is higher than that for recrystallizing the amorphous silicon. After laser irradiation, the surface unevenness has been remarkably smoothed.

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A novel surface measurement system has been developed in order to evaluate the process of fabricating micro lenses. White light interferometer is conventionally applied for the flat surface and spherical surface of lens mold. However it is difficult to evaluate the non-spherical lens mold by using the white light interferometer. We propose light scattering method which applied the extended TIS model in order to evaluate a surface texture of a non-spherical microlens mold. In this report we describe the experiment result which measure the surface roughness of flat Si wafer coated with Cu. The developed system can detect scattered light pattern from the surface, and the roughness is agreed with of TIS.

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Ultra-precision diamond turning machine has the slide motion error which consists of the straightness error and the parallelism error. However, measurement of the parallelism error between the slide axis and the spindle axis of a diamond turning machine is difficult by the conventional reversal method. In order to measure not only the straightness error but also parallelism error, the rotating reversal method is proposed. Two capacitive sensors are employed to scan the cylinder workpiece which was installed on the spindle. The evaluate straightness error of the Z-slide of the ultra-precision diamond turning machine was to be about 100 nm and parallelism error was measured to be approximately 1 arc-second of the Z-slide by the rotating reversal method over a measurement range of 126 mm

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Microfabricated structures such as semiconductors and MEMS keep shrinking as nanotechnology advances. Demand that measures microfabricated structures has risen. The optics and electron beam have been mainly used for that purpose, but the resolving power of the optics is limited by the Rayleigh limit and it is generally low for defects at sub-wavelength geometries, while the scanning electron microscope needs vacuum and induces contamination in measurement. In order to find a solution to these problems, we propose the novel optical inspecting method for the microfabricated structure using standing wave shift. This method is based on a super-resolution algorithm in which the inspection system's resolution exceeds the Rayleigh limit by shifting standing wave with the piezoelectric actuator. In this report, we carried out simulation and basic experiment of 2-dimensional super-resolution.

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In these days, ultra precision, high complexity and high efficiency of fine-fabrication using cutting tool are required. Not only performance of machine tool but also downsizing of high accurate working tool itself has been an important issue to realize the requirements. In this study, on-machine tool measurement technology using laser diffraction which is able to manage micro tool and able to post in the machine tool has been establishing. In this article, the on-machine tool measurement device applying dual wavelength is developed. We use the developed tool measurement device, installable size for machining center, to evaluate fundamental measurement performance.

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This paper describes simulation results of positioning the tool edge top in 3-directions by using an optical sensor. In the optical sensor, a laser beam from a laser diode is focused to generate a small beam spot with a micrometer-order diameter at the beam waist and then received by a photo-detector. When the tool edge is brought into the light, the light intensity detected by the photodiode will be changed depending on the position of the tool edge in the light. Computer simulations were carried out to confirm the relationship between the photodiode output and the position of the tool edge top.

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The specular surface of mold die etc were not obtained suitable diffuse reflection for non-contact CMM used laser probe, therefore the surfaces were treated white powder sprayed in order to change for generated diffuse reflection surface. Measurement error of non-contact CMM was increased that ups and downs of surface was formed by human skill white powder sprayed as serious influence, therefore the experiment was studied to extract significant factor for the automation of white powder sprayed work. As a result, it could be extracted significant factor for example sprayed method etc.

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Non-contact coordinate measuring had been performed high efficiency measurement by wide area scanning, but the measurement error was increased by the influence of surface properties and optical characteristics. Here, Relation between optical characteristics and surface roughness were studied in order to determinate measurement error based on optical characteristics of workpiece surface. As a result, it is suitable for index of evaluation that Rz (JIS), R3z as roughness average present and Rdc as bearing ratio curve present was represented for scattering of surface.

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Recently CAD/CAM systems is familiarized, and products design including the free-form surface came into wide use. Now a lot of tool-path patterns are proposed for milling process of free-form surface. Therefore, it is necessary to select an appropriate tool-path pattern according to the form of surface. For such reason, the selection of appropriate tool-path based on the form of surface represented by NURBS is studied. In this research, three tool-path generating methods, iso-parametric method, iso-planar method and constant scallop height method, were taken for comparison. A free-form surface was machined with three methods, and then the machined surfaces were measured. The difference between Z coordinates of the measured point and that of the target surface was defined as the error margin in order to evaluate performance of tool-path pattern. The results showed that proper selection of milling method would get the good surface integrity.

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In the field of mobile phone, the demand of the image stabilizer due to the development of the vest pocket camera for the mobile phone in increasing and it is needed to develop the stage where the image sensor on it can quickly move. This paper presents a micro linear stage which has a high speed, a long stroke and can perform precision positioning. This stage which is based on the principle of friction drive has a long stroke and a high resolution of up to 6 nm. In this research, by using small and strong magnets as friction elements, the change in the frictional force with respect to changes in posture can be controlled, and this provides an advantage of stable drive in free postures. The characteristic of the stage is also presented.

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This paper describes a highly sensitive two-axis angle sensor by using a single cell photodiode for measurement of surface profiles and error motions. The sensor, which is based on the principle of the laser autocollimation, employs a laser diode as the light source. The reflected beam from the target surface is received by an autocollimation unit consisting of an objective lens and a light spot position-sensing detector located at the focal position of the lens. It is confirmed that the sensor sensitivity depends on the spot size on the focal position and a single cell photodiode is employed as the light spot position-sensing detector to sense the position of the light spot at the focal position. A prototype two-axis angle sensor with a dimensional of 65 mm (W) × 70 mm (L) × 40 mm (H) is designed and constructed. Experimental results have shown that the sensor has a sensitivity of ±3 %/arc-seconds and a resolution of ±0.03 arc-seconds.

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Three-dimensional micro-structured surface including a micro gear and aspheric lens is used for industrial robots, medical devices, and optical as well as printing equipments and so on. To measure such surface profile, micro-stylus whose tip ball is less than several micrometers in diameter is necessary. This paper describes the development of a micro-stylus with tip balls of 30μm in diameter. The tip ball is silica spheres with feature of high accuracy and affordable price. Additionally, to reduce the effect of stick-slip oscillation caused by friction, which is crucial problem, we developed a micro-tapping stylus using PZT actuator. Using the micro-tapping stylus, surface profile measurement of a micro gear is carried out.

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This paper presents the machinability of AZ31 magnesium alloy by HSS, cemented carbides and DLC-coated cemented carbides drills. In this experiment, 30 mm thick work-piece was drilled by drills of a diameter of 3 mm (aspect ratio 10). The experimental results show that burrs occur at the drill-hole exits when HSS drills with a point angle of 116 degrees are used. On the other hand, burrs are not found at 120 degrees. The carbide tools showed a longer tool life at cutting feed rates faster than 100 mm/min and the DLC coated tools showed small surface roughness small compared to the other tools.

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