QFD has been used to reflect the needs of customers in products, while TRIZ was developed to assist engineers in finding innovative solutions to technical problems in product development processes. However, no method has been proposed to integrate QFD with TRIZ effectively. A new method named the Innovative Product Development Process (IPDP) is developed, which systematically integrates QFD with TRIZ and enables the effective and systematic creation of technical innovation for new products. In IPDP, the target products' functions and mechanisms are expanded in parallel into hierarchical structures, and the mechanism that most requires technical innovation is specified from an analysis of customers' needs by calculating a mechanism weight. Then, the technical problems to be solved are defined by considering the relationship between the specified mechanism and corresponding functions or quality characteristics, and technical innovation is executed by applying TRIZ. The effectiveness of IPDP was confirmed by applying it to the technical innovation of a "washing machine."

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This study has proposed a new coordinate measuring machine (CMM) based on a spatial in-parallel kinematics consisting of closed loop link mechanism. In this report, the construction and the simple calibration have been described for developed CMM. The CMM employs specially made spherical joints and revolutionary joints, precise linear scales built in three prismatic joints, a touch trigger probe and an octahedral truss frame. Variations in the length of the prismatic joints driven by AC servo motors move the probe in three-dimensional space. When the probe touches the measuring object, the probe coordinates are calculated from the scale values. Moreover, the simple calibration of the CMM has been performed by measuring the block gauges in XYZ directions. The kinematic parameters on the location of the spherical joints and the initial length of the struts have been adjusted gradually by repetitive operation so that the lengths of the gauge are correctly calculated. The results of test measurement show that the standard deviation of measured data, or the measuring repeatability is less than 0.21 μm. Measured deflections, moreover, are less than 10 μm when measuring the gauge blocks with maximum length of 50mm.

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A theory of light scattering is described for particles and geometric defects on a flat surface which are very small compared with the wavelength. The differential scattering cross section for small objects with an arbitrary shape is calculated to the electric-dipole approximation. The image of scatterer through a magnifying lens is also obtained by combining a conventional optical theory. This calculation method is applied to particle, projection, pit and scratch on the silicon wafer, the shape of which is assumed to be rectangular in order to simplify an algebraic expression. The characteristics of light scattering are the followings: (1) The intensity of light scattered by particle is proportional to the 6th power of scatterer size and the scattering of p-polarized light is larger than s-polarized one. (2) The orientation dependence of light intensity scattered by particle, projection and pit takes a shape of doughnut like a Rayleigh scattering, but the light scattering due to scratch is strong only in the direction perpendicular to the scratch line. (3) The image of scatterers shows a diffraction pattern caused by the aperture of lens.

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It is necessary to have equations of motion for the numerical simulation of a dynamic system such as mechanical ones. One of the methods to derive equations of motion is to use the Lagrange's equation. However it is not easy to apply the Lagrange's equation to the system that includes linkage mechanism. And, the Lagrange's method usually needs to do the derivation of equations of motion over again from the beginning even when the object model is modified partly. This paper proposes the employment of the Bond-Graph modeling to derive the equations of motion for mechanical systems with linkage mechanism. A forced steering railway vehicle is considered as an example of the application. In the example, steering linkage mechanism is added to conventional vehicle model whose equations of motion are already known. Using the, Bond-Graph modeling only for the added linkage part, the modification of the related equations of motion is achieved. Here, two kinds of linkage mechanism are examined, and the validity of the modified equations is demonstrated in the numerical simulation. Then it is confirmed that the Bond-Graph modeling is useful to derive the equations of motion of a rail vehicle added with some linkage mechanism.

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To understand the behavior of particles within optical traps, dynamic analysis of laser trapping is necessary. A mathematical model has been established, which examines all the forces acting on a particle such as trapping force, gravity, buoyancy and Stokes drag. A simulator has been developed based on our mathematical model to define the motion of arbitrary shaped particles exerted primarily by trapping force and optical torque. The movement behavior of a designedtool made of silica trapped in air was predicted and the results showed that high rotation speed can be achieved when the torque produced by the laser beam is balanced by the drag torque exerted by the surrounding air. This gives a good verification that designed-tool made of silica or diamond trapped by laser beam can be used for nano-meter machining.

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Micro electro-discharge machining has suitable properties for micro hole and slit. However, it has been difficult to guarantee the machining quality due to the lack of evaluation methodology. Vibroscanning method, originally invented at the Univertsity of Tokyo, can measure the inner profile of micro holes nondestructively. By utilizing the vibroscanning measurement probe, on-the-machine measurement setup of micro EDM has been built. In the experiment, inner profile of EDMed micro hole was clearly observed and its accuracy was proved to be better than 1μm. Two-dimensional vibroscanning method has also been developed, which indicates the possibility of full three-dimensional evaluation of micro holes.

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In this paper, a new method of selective deposition on glass substrates is proposed. Metal powders placed on a glass substrate are irradiated by a laser beam through the glass from the other side and consequently the powders are sintered on the glass substrates. Soda glass, Pyrex glass and silica glass were used as substrates from the viewpoint of their thermal properties, and stainless steel (SUS316L) powders with grain size of 7μm and 60μm were chosen. An Ar ion laser beam was used because glass is highly transparent. Fine metal powder was deposited on every glass substrate, and the size of the deposited metal powder was controllable from 120μm to 840μm in diameter, and from 45μm to 330μm in height by varying the laser power and irradiation time. In the experiment, changing the glass substrate revealed that the adherence of the metal powder was the strongest on the soda glass of all the glasses. Also varying atmosphere and powder size clarified that the metal powder adhered to glass better in air than in vacuum and with fine powder than coarse powder.

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A high speed milling is being received with keen interest in the manufacturing shop where cut hardened alloy tool steels used for metal molds. However, there are some difficult problems, such as high cutting temperature, low stiffness of NC machine, low follow-up ability of NC servo motor etc. This paper deals with cutting phenomena such as cutting temperature, tool life etc. when milling the steels using cemented carbide with grade K10 under various cutting conditions. Furthermore, based on the cutting temperature measured using a work-tool thermocouple technique, the tool wear rate is discussed. The results obtained are as follows. The longest tool life is obtained at cutting speed of 110-130 m/min and feed of about 0.05 mm/tooth. The relationship between work hardness and tool life is linear for each cutting speed on the semilogarithmic coordinate. When the cutting speed is 130 m/min or more, the tool life correlates very closely with the cutting temperature. (Ti, Al)N coated tool has longer tool life of about 2 times and higher thermal resistance of about 100 t compared with carbide tool.

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In high speed surface grinding, the grinding fluid is excluded from the front of the grinding wheel by bubbles. These bubbles are made as a result of the air of boundary layer on the grinding wheel surface being mixed in the grinding fluid. To make clear this phenomena between the fluid and the bubbles, the pressure distributions of the ground surface are measured. Composition of WA wheel used in the experiment is as follows:bonding materials are Vitrified and Resinoid ; mesh is #120 and #1000, and the fluid is water. Conclusions are as follows: 1) In high permeability of the wheel, the generated pressure at the front of the grinding point causes the grinding fluid to flow into the porous wheel, therefore the pressure is not high. 2) In high permeability and high surface roughness of the wheel, the grinding fluid is found insufficient even in a low rotational speed.

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This paper describes the approximate equation on elastic modulus of bridge type grinding stones. This equation is deduced from the acoustic model based on the propagation of the elastic wave on condition that grains and bond bridges in the grinding stone have sufficiently adhered. The elastic modulus measured by ultrasonic pulse method is compared with the calculation from this approximation in order to confirm the accuracy of the approximation. As a result, it is confirmed that the measured elastic modulus is a bit lower than the calculated one, and the both qualitative tendencies agree well with each other. As the elastic modulus calculated by this equation at pore ratio of 0% agrees well with the approximation of the matrix type grinding stones shown in the first report, the approximate equation can be applied to elastic modulus not only of bridge type but also of the matrix type grinding stones.

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Continued to the first report, this paper deals with the behavior of cooling generated by vortex tube leading to a set of angular contact ball bearings operated which are high speed in machine tool spindle. The main purpose is to make clear the bearing cooling mechanism by measuring the temperature and flow situation of cooling air, which are exerted by the air flow layer produced from the rotation of bearing retainer, and the bearing circumference temperature distribution. As a result of the experiment, the followings are clarified. (1) If the distance between bearing and cooling air nozzle is 25 mm or less, cooling effect is obtained almost the same. (2) The temperature of cooling air has a little change by arrangement angle between rotating directions of bearing and the cooling air nozzle. (3) As for the cooling air, the temperature can rise immediately after jetted from a nozzle and keep 0 degree or less to the location where is around 15 mm apart from the nozzle. (4) The cooling air supplied to bearing does not reach at the inside of bearing, and revolves around perimeter of bearing.

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When the shot peening process is employed in order to improve the bending fatigue strength of a gear tooth, there is a fear that the surface durability of the shot peened surface may reduce because of degradation of its surface roughness. In this study, the surface durability of the carbo-nitrided steel rollers besides the carburized ones was investigated using a highly loaded two rollers contact fatigue testing machine. It was confirmed that only the shot peening could scantly improve the surface durability because it is very hard to smooth the surface roughness by control of the shot peening conditions. Then, the barreling process was employed to improve the surface roughness, and it was clarified that the surface durability of shot peened rollers was remarkably improved by the barreling process. Also, it was shown using the D-value that the pitting limit increases and amount of wear decreases appreciably when the surface roughness becomes small. Pitting occurred on two kinds of case-hardened steels in the present experiments have always originated at the surface with/without shot peening process. The crack for pitting has rapidly propagated in the inside where a fatigue will be produced by a repeated shear stress, and a large pit (spalling) has immediately occurred all over the face width.

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Recently the authors have proposed the metal jet technique which can make 3-dimensional micro structures made of metal drops. In this paper, solder jet was used to generate 2- and 3-dimensional electric circuit. Typical examples of 3-dimensional circuits are demonstrated and the electric resistivity and bonding strength between metal drops were measured. Further, some post processes are proposed to improve the resistivity of circuit made in the laboratory air.

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In this study, atomic diffusibility of liquid metals on glassy carbon and graphite substrates is investigated by ab initio molecular orbital calculations using AMOSS program. Ethylene-and distorted ethylene-metal adatom models are introduced for the atomic structures of glassy carbon-and graphite-liquid metal systems, respectively, and molecular orbitals and total energy in the most stable state are obtained by the restricted open-shell Hartree-Fock (ROHF) method. Consequently, in the case of ethylene- or distorted ethylene-metal adatom model, corresponding to HOPG- or glassy carbon-liquid metal system in which atomic diffusion occurs, it is revealed that the carbon interatomic bond is weakened by the formation of the occupied orbital due to the hybridization between the metal p- or d-orbital and ethylene antibonding orbital.

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This paper presents a design method of friction compensator for a feed-drive system of NC machine tools. The feed-drive mechanism consisting of motors, ball-screws and a table, in circular motion, yields large quadrant glitch at the position changing the direction of each axis, It is well-known that this phenomenon is caused by static friction acting upon feed-drive mechanism. As the quadrant glitch can be simulated with friction model proposed by one of authors, a friction compensator based on the model and its control algorithm are newly designed. From the experiment using an actual XY-table, it is confirmed that the quadrant glitch is diminished effectively whenever feed-rate and radius in the circular motion are changed.

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The temperature of cutting tool in high speed endmilling is measured using a two-color pyrometer with an optical fiber. This pyrometer has a flat response for the square-wave signal up to approximately 400kHz, which is enough speed to measure the temperature of an endmilling cutter passing at a cutting speed of 628m/min. The influence of cutting speed v and feed per tooth f on the cutting temperature at the flank face of the cemented carbide insert is investigated. The heating and cooling characteristics of the cutting tool during an intermittent cutting cycle are also examined. In dry cutting of carbon steel, the cutting tool temperature θα rises rapidly with the increase of cutting speed and θα reaches approximately 770°C at v=628m/min. The feed per tooth, however, has less effect on cutting tool temperature. The temperature change during an intermittent cutting process is about 150°C when v=471.2m/min and f=0.047mm/tooth. The temperature distribution along the contact edge between a tool and workpiece is almost uniform although those at tool tip and boundary region are somewhat higher.

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This paper deals with the two adaptive control functions and their integration for drilling process. One is the feed rate over-ride type adaptive control. In our study this function is also quite effective for the common axial depth applications of high speed drilling of automotive parts. The other function is an automatic pecking which is shown to be a useful method to avoid the tool breakage due to the chip jamming in the case of deep hole drilling. In both cases, the cutting torque and thrust force are monitored through the motor current of the spindle motor and the feed drive servo motor, and additional sensor installation is not necessary to realize adaptive control. The integration of those functions in the whole drilling process has been studied and the intelligent drilling scheme is proposed and tested.

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At present, the cold working die steel, SKD11, is commonly used as the metal molds due to its superior wear and corrosion resistance. In electrical discharge machining (EDM) of die steel, a hard white layer, which is different from the base metal, is formed on the metal mold surfaces caused by rapid heating and cooling. Cracks and micro-craters appear on the surface of the white layer depending on the machining conditions used. Such heat-affected zones (HAZ) can greatly shorten the life of metal molds. In this study, the method of laser surface modification with melting has been proposed as a new surface modification method. This method can eliminate defects, such as cracks and micro-craters, by melting and solidifying HAZ using a laser beam as the heat source. As a result, the laser-irradiated surface, in the absence of an absorbent, is converted into a flat surface with neither cracks nor micro-craters that are generated by EDM. It was found that tensile stress with values ranging from 55OMPa to 850MPa is retained in the irradiated surface, and the residual stress can be removed by aging treatment at 580-600°C.

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In the atmospheric pressure plasma CVD system, improvement of the process environment by utilizing the reactivity between SiH₄ and H₂0 was examined. The cleaning gas containing He and SiH₄ was circulated by the gas circulation system in heated condition, and H₂O which remained in the process atmosphere was measured by APIMS (Atmospheric Pressure Ionization Mass Spectrometer). Hydrogenated amorphous silicon (a-Si:H) films were deposited by the atmospheric pressure plasma CVD before and after the SiH₄ circulation cleaning. In order to evaluate the effectiveness of the SiH₄ circulation cleaning, contaminations such as O, N and C were analyzed by SIMS (Secondary Ion Mass Spectroscopy). Furthermore, the photoconductivity and the dark conductivity were compared. The results showed that the H₂0 concentration in the process atmosphere drastically decreased by the SiH₄ circulation, and the O content in the a-Si:H film decreased similarly. The O content in the film after the SiH₄ circulation cleaning was 5×10¹⁸ /cm³, which value was as same as or less than that by the conventional plasma CVD technique. The dark conductivity decreased, and the electrical property was improved. It was because the O content in the film decreased by the SiH₄ circulation cleaning.

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Neither the processing phenomenon nor the rule factor of nano-scale cutting is not still enough understood. It is an important problem to understand them in order to establish the processing technologies of minute parts. In this paper, the result of nano-scale cutting of single crystal silicon by using friction force microscope is described. The (100) surface of single crystal silicon was etched by KOH solution after nano-scale cutting of 15 μm × 15 μm area. It was found the etch rate was extremely different between the cut area and non-cut area. The cut area remained as it was little being etched. Dependence of remaining height on normal cutting force and cutting velocity and KOH solution concentration was examined. The new processing technique of micro-structure was proposed by applying the above-mentioned experiment result.

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This paper describes collection of laser ablation fragments. Polyimide was ablated by an ArF excimer laser. Firstly, emission of laser ablation was examined by spectrophotometry and ablated fragments were captured on cellophane sheets. From SEM observation of captured fragments, the diameter of fragment was classified into four groups approximately 50nm, 100nm, 200nm and 500nm. Secondly, fragment collection on tungsten needles was tried. Electric fields were applied to needles which were set 1mm spacing. As a result fragments were collected on both electrodes and the amount of collected fragments was almost equal. The amount was in proportion to the intensity of electric field and the number of laser pulses. Silica glass and Teflon were also tried in similar manner. Then, fragments from silica glass were collected on both electrodes similarly to polyimide, while fragments from Teflon were mainly collected on anode.

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