We have developed a new instrumentation technique for Si crystal growth process of Czochralski (CZ) method for the purpose of the productivity improvement. In this paper, we developed the online measurement technique for diameter profile of Si crystal in growth furnace. Our new technique can measure the crystal diameter profile with higher accuracy than conventional optical measurement. The features of this technique are the data correction method and the elimination method of the effect of crystal swing. The measurement error of maximum diameter is within 0.18mm, and the measurement error of minimum diameter is within 0.09mm. This technique contributes to the improvement of CZ Si crystal productivity.

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Two finite element models are developed to calculate transverse vibrations of axially moving belt : one is a string type model without bending rigidity and the other is a beam type model with bending rigidity. A conserved quantity for these models is derived in matrix form and used to check the quality of numerical calculations. To demonstrate the validity of these finite element models, calculated results according to both models are compared with an exact solution for a belt with zero bending rigidity. The beam type model is also applicable when the bending rigidity of the belt is zero, and gives more accurate result than the string type model with same number of elements. In addition, result according to the beam type model is compared with Kotera's calculation solving integral equations numerically for a belt with bending rigidity, so that it is shown that the beam type model gives more accurate result than the integral equation method.

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The purpose of this study is to know the fluid flow of an oil damper by a numerical analysis, so as to obtain the exact values of the damping coefficient of an oil damper. The Finite Difference Method (FDM) was used for solving the governing equation of the fluid caused by the moving piston. Each time step proceeded in the Fractional Step method, and the Arbitrary Lagrangian-Eulerian (ALE) method was adopted for the moving boundary. In order to stabilize the computation in the moving boundary problem, we employed the masking method with a single block grid system. That is, the algebraic grid generation using stretching function was used for the moving piston. The time dependent coordinate system in physical domain which coincides with a contour of moving boundary is transformed into a fixed rectangular coordinate system in computational domain. The computational results were compared with the experimental ones and the approximate analytical solution. The results of present analysis show good agreement with the experimental results over a wide range of piston diameter.

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In recent years, Active Magnetic Bearings (AMBs) characterized by non-contact support without mechanical loss have been applied in industrial rotors. The purpose of this research is to develop a flexible, overhanging rotor supported by AMBs to pass smoothly the 2nd bending mode critical speed. This paper deals with the following topics : (1) Controller design based on the phase adjustment method and the evaluation of the designs using sensitivity functions, (2) Evaluation of the designs using a new method, called Q-value function, and (3) Application of modal balancing method to pass the 2nd bending mode critical speed.

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Active control of a vibration isolation table using pneumatic actuators is studied in this paper. The vibration isolation table is supported by four pneumatic actuators at corners of the square rigid table. A 3DOF physical model of the vibration isolation table is constructed with taking account of redundancy of the actuators and sensors. We introduce a method to determine the air pressure of each actuator to minimize the error between the average pressure of the actuators and the air pressure of each actuator. The regulator for the pneumatic actuator is driven by a stepping motor. Characteristics of the transfer function from input pulse for the stepping motor to the air pressure of the actuator are investigated experimentally and the mathematical model of the actuator is constructed as a second order delay system. Type I digital servo system is applied to control the vibration and position of the vibration isolation table. Control performance of the system is verified experimentally and the results are shown in figures.

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In adaptive output feedback control based on almost strictly positive real conditions, a technical difficulty arise when the multi-input, multi-output (MIMO) system under consideration is non-square. To overcome this problem, the idea of multirate sampled-data control will be proposed. That is, through careful choice of faster input sampling rates, we create a lifted discrete-time system which has the same number of inputs and outputs without the causality constraint. The output feedback based adaptive control strategy can then be applied to this lifted system under certain conditions. In this report, we also propose a robust adaptive output feedback controller design scheme for non-square MIMO systems using the multirate sampling strategy which can solve the causality problem and show that all the signals in the resulting closed loop control system are bounded.

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This paper proposes a controller design method of feed drive systems to improve the multi-axis synchronous accuracy. In the design method, the velocity loop control systems are designed based upon “the Partial Model Matching Method”, and the positional loop control systems are designed by using the frequency characteristics of the designed velocity control loops. A feed forward controller which can compensate servo delay is also proposed. Parameters of the proposed controllers can be determined systematically without trial and error. The effectiveness of the proposed method was evaluated through the experiments and simulations. The experiments were carried out by using the X-Y stage system. The effectiveness of the proposed method in the multi-axis synchronous motion including rotary axes was also evaluated by the simulations of multi-axis machining. As the results of the experiments and simulations, it is clarified that the proposed method can greatly improve the synchronous accuracy.

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Systems with slight Coulomb friction at the supporting point have very small dead zone in which the system stops after free oscillation. Small stiffness makes the dead zone very wide even under slight Coulomb friction, because it is determined by the ratio between Coulomb friction and stiffness. In the previous study, it is theoretically and experimentally clarified in the neighborhood of buckling point that slight Coulomb friction produces large dead zone around the stable and unstable steady states of the pitchfork bifurcation in the case without Coulomb friction. Therefore, it is very important in the analyses on behavior of the low stiffness system such as flexible structures in space agency, to estimate the value of Coulomb friction. In this paper, we propose an experimental identification method for bending moment due to Coulomb friction at the supporting points of hinged-hinged beam. The moment due to dynamic friction is identified from experimental free oscillation by separating the effects of viscous damping and dynamic friction. For static friction, we use the dead zone in bifurcation diagram due to static friction. In the vicinity of the buckling point, the zone is very wide and its boundary is easily obtained from experiment. We show an identification method of the moment due to dynamic friction from the experimentally obtiained boundary.

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First, transient response of a bar-type ultrasonic motor is measured using laser-doppler-velocimeter in order to show the relationship between input parameters and the non-linear dynamic characteristics. Next, dynamical model of ultrasonic motor is constructed. The piezoelectric ceramics and stator's vibration are modeled as a second order system considering non-linear terms at piezoelectric ceramics and elastics of metal part of the stator. At the interface between the rotor and stator, three-dimensional discrete model using springs and dampers at the contact surface is introduced in order to calculate the friction force between them. Coulomb's friction model was introduced considering stick-slip at contact area. As a result, the validity of the mathematical model was confirmed by showing that simulation results are in good agreement with those obtained by measurement.

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In this paper, seismic response analysis is carried out both experimentally and numerically for a base isolation device with pseudoelastic shape memory alloy (SMA) springs as restoring force components. Owing to the material nonliniarity and the geometrical nonliniarity, the SMA spring used in the device has well-defined softening, or “force limiting”, property that can suppress the acceleration response of the superstructure by limiting the seismic force transmitted from the ground. Numerical simulations are conducted using Preisach-based SMA spring model. Then, assuming the scalability of the restoring force v.s. displacement curve of the SMA spring, seismic responses of the devices with SMA springs which have various restoring force characteristics are investigated, numerically. From their results, brief design criteria are suggested.

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The vibration characteristics of laminated composite circular cylindrical shell partially filled with liquid was investigated and compared with the isotropic shell. Especially, the differences of the vibration characteristics between the laminated and isotropic shells and the mass effect of liquid on the vibrations of the shells were clarified experimentally. The laminated composite circular cylindrical shell was made from five cross-ply layers of CFRP prepreg. The isotropic circular cylindrical shell with the same size as the composite shell was made of steel. In the experiment, these circular shells were mounted on a vibration table with a clamped lower end and a free upper end, and excited horizontally by white noise. The vibration displacements of laminated shell were measured by non-contact optical fiber sensor, and those of steel shell was measured by eddy current sensor. The natural frequencies and mode shapes were identified by modal analysis using STAR-system software.As the results, in the case of empty shells, the frequencies of laminated shell is high compared with the ones of isotropic shell in the region of large circumferential wave number. When the shells were filled with liquid and increasing in the liquid height, however, the frequencies of laminated-shell is lower than ones of isotropic shell in that circumferential wave number region. And bulging-type modes of laminated shell having partially filled liquid appeared at small circumferential wave numbers by comparison isotropic shell.

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The seismic-proof design of a large-scale cylindrical water storage tank has been an important issue for enormous earthquake. For enhancing its reliability, it is necessary to study the vibration behavior of the tank in more detail. This paper describes the results of a vibration test with a 1/10 reduced scale model of a large-scale cylindrical water storage tank, and also refers to the dynamic fluid pressure distribution and its influence on the seismic-proof design. Considering the differences between the experimental values and numerical design ones, it becomes obvious that there is a discrepancy between the positive and the negative pressures of the dynamic fluid pressure and that the dynamic fluid pressure depends on the acceleration magnitude. And it is suggested that such phenomena are caused by oval-type vibrations. They, however, have little effect on the seismic-proof design of the tank in the range of acceleration used in this study.

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In this study, a vibration experiment with a reduced scale model of a large-size cylindrical water storage tank is performed in order to investigate the nonlinear vibration responses of the cylindrical tank when the beam-type and the oval-type vibrations are coupled. The sinusoidal sweep test is conducted by varying the input acceleration from smaller to larger input. As a result, the resonance frequency shifts to the lower frequency region and the response magnification factor becomes smaller as the input acceleration level becomes larger. Furthermore, when larger input is applied, the oval-type vibration has a subharmonic resonance of order one-half, and its displacement-amplitude grows up significantly. It can be assumed that the large amplitude of oval-type vibration generates a geometrical nonlinearity for the beam-type vibration.

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The decrease of wheel load variation is one of the most important subjects in order to further enhance stability, safety and ride comfort of high-speed train. In this paper, we conduct the simulation analysis on wheel load variation in order to investigate the influence of the specifications of both vehicle and track on wheel load variation of high-speed train, and in order to derive the appropriate specifications to decrease the wheel load variation. As a result of the eigen value analysis and the time history response analysis, we figured out as follows : The wheel load variation is mainly caused by the vertical motion of the wheel/rail at the basis on the primary natural vibration of the wheel/rail system; the wheel load variation is influenced a great deal by the relation between the natural frequency of wheel rail and the frequency determined by both running speed and the interval of support springs.

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This paper describes the research and development of the new type of isolation systems suitable for light-weight-houses. The Basic concept of the new isolation system is to realize cost effective design without any reduction in the isolation performance. This paper presents results obtained from experimental and analytical studies to evaluate isolation performance of the new isolation system. In the experiment, static tests were first carried out using a 0.20 scale model (55kg mass, and 0.50m × 0.50m × 0.27m size) for isolated-light-weight-houses model which was supported by two linear ball bearing and, restring force was given to superstructure by transversal stiffness of a coiled spring, so as to examine restring force characteristic for the coiled spring. Second, dynamic tests were implemented in order to investigate the isolation performance of the isolation system in actual seismic waves. In analysis, seismic response analyses for the scale model, regarding the vibration tests using the actual seismic wave, were carried out to evaluated the response analytical method for the isolation system using the coiled spring. From these results, the following are clarified. (1) Analytical results for the isolated-light-weight-houses model agree well with experiment results. (2) The isolated system using the coiled spring reduced responses acceleration sufficiently.

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The Immune Algorithm (IA), which is optimum method based the human immune system, is suitable for gaining several solutions at once. This method is similar to Genetic Algorithms (GA), and is hoped to be able to use several local rules of GA. On the other hands, IA may have the demerit that is hard to deal with many parameters. In this paper, we suggest the improved Immune Algorithm. This method is improved by review of Immune System, and uses both secondary response and response control by endocrine system. It's hoped that new added functions affect searching ability. Additionally, the effect may be able to cut one of complex parameters. This method is applied to some simple problems that search the extremum in the functions and traveling salesman problem. As the results, it's able to control one of parameters depending on the searching situation and suggested the potential of cutting parameter. The validity of this method is checked.

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Since Darwin published “the theory of evolution”, studying animals has been contributing to understanding human psychology and also having effects on robotic researchers. We then started to study interaction between rats and robots to develop a framework of adaptive interaction between animals and robots. Therefore, a small mobile robot, WM-6 and experimental setup were developed to perform the experimental study on interaction between rats and robots. The objective of this paper is to investigate task teaching to the rat using the robot. Referring to the technique of “shaping” proposed by Skinner, the teaching behavior algorithm for the robot was developed. This algorithm was implemented into the robot and setup. The experiment using 5 rats, three of them are experimental subjects and the others are control subjects, was performed to evaluate this algorithm. The experimental subjects leamed the task while the control subjects didn't. Thus, the teaching behavior algorithm was verified.

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Recently, robot systems which support surgery are actively developed. Although force sensation is indispensable for surgeon to operate minimally invasive surgery safely, conventional robot systems cannot transmit force sensation. In this paper, it aims at developing the technology for transmitting force sensation in medical treatment without a force sensor in consideration of safety. Our proposed method is based on “symmetric position servo type bilateral control”, which control rule needs not any force sensors. However, it has a problem that large force is required for the operation due to the influence of robot dynamics. To solve this problem, control input based on the information of acceleration and velocity of master and slave is added, and control rule is switched according to the state of the estimated environment. In the experiment using a robot of multiple degrees of freedom, it is confirmed that the influence of robot dynamics can be reduced. In addition, an excellent bilateral control with small operation force is achieved by the proposed method without using a force sensor.

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This paper describes a method of assisting muscle functions at gait initiation using a human leg model. We analyzed a human motion of walking mechanism at gait initiation by measuring 3D position data and force plate data and surface EMG. It is generally accepted that the backward shift of the COP at the center of pressure of the sole of the foot is very significant at gait initiation starting from the standing upright position. The mechanism generating the backward shift of the COP is discussed according to measured data. The human leg model with the same size and the approximation weight as those of a subject was constructed to simulate the condition beginning to walk from standing upright posture. Air cylinder actuators, serving as muscle functions, were installed in the part of muscle on the leg model. Further, a small actuator is equipped at the part of the heel to produce the backward shift of the COP at beginning of the walk. Gait initiation is well simulated when actuators were operated synchronizing with the surface EMG. Based on these results, a simple method for initiating the walk was discussed in relation to walking mechanisms analyzed.

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Conventional humanoid robots cannot achieve human-like walking patterns. The reason is that human walking patterns include singularity configurations, i.e. configurations with extended knees. Such kinematic singularities cause spurious joint motions. In other words, the humanoid robots cannot handle the singularity problem. On the other hand, humans make use of singularity configurations, because at such configurations large forces in certain directions can be generated. Therefore, singularities play an important role for creating efficient walking patterns. In our previous work, we proposed the Singularity Consistent (SC) Approach that can handle the singularity problem without instabilities. Until now, the approach has been applied to various manipulators. In this paper, we apply the SC approach to a walking pattern generator for a humanoid. Some issues and their solutions will be addressed. Experimental results show the effectiveness of our approach.

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A human being utilizes its singularities to achieve efficient walk. A robot, however, cannot handle singularities, and hence, extremely large joint velocity is generated. We have so far proposed the Singularity Consistent (SC) Approach that can handle the singularity problem without instabilities, and applied the method to generate static walk for a humanoid. In this paper, we propose a method to generate a walking pattern through singularity neighborhood, by using proper ankle control and pattern generation based on the spherical inverted pendulum model. Experimental results show the effectiveness of our approach.

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Ground Penetrating Radar (GPR) is a promissing sensor for landmine detection, however there are two major problems to overcome. One is the non-planer (e.g. rough and/or undulating) ground surface. It remains unremovable clutters on a sub-surface image output from GPR. Geography adaptive scanning is useful to image objects beneath non-planer ground surface. The other problem is the distance between the antennas of GPR. When imaging the small objects such as an anti-personnel landmine buried in shallow depth, it increases the nonlinearity of the relationship between the time for propagation and the depth of a buried object. In this paper, we modify Kirchoff migration so as to account for not only the variation of height and pose of the sensor head, but also the antennas alignment of the vector radar. The validity of this method is discussed through application to the signals acquired in experiments.

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The world's first 10-way micro switching valve chip as one of Biochemical IC chip was developed successfully. This switching valve chip has a special rotary mechanism with the silicon rubber leak-preventions and the precise auto-positioning mechanism. This chip succeeded to switch ten outlets from one inlet without dead volume under high leakage pressure (>700 kPa). Since the micro fabrication was made by our original “hybrid microstereolithography” (hybrid-IH process), the micro assembling and bonding are not needed. This chip is generally useful for various kinds of micro chemical devices.

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This paper presents the measurement of tactile sensation using a sensor system for collecting tactile information. First, various tactile feelings of fabrics are collected through a questionnaire based on the paired comparison semantic differential method. Furthermore, the factor analysis is introduced to evaluate and classify the feelings. Next, an active sensing system using the piezoelectric effect and the pyroelectric effect of a PVDF (Polyvinylidene Fluoride) film is assembled. The sensor is made of a PVDF film and a soft rubber. The surface of the sensor can be heated through temperature control. The sensor is attached on the tip of a robot finger driven by a piezoelectric bimorph strip and the root of the finger is mounted on a linear slider. Two kinds of active sensing, contact and slide, are introduced to collect the information on tactile warmth and feelings of vibration, respectively. Measurement using the sensor system is carried out on the sample fabrics. Features on the collected data are extracted as the sensor outputs for the evaluation of tactile sensation. Comparison of the results shows that the sensor system well describes human tactile perception.

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Dissimilarly to brake discs for trains and automobiles, several tens of small holes are opened in the brake discs for motorcycles for ventilation and cleaning the pad surfaces. When an extreme braking torque is cyclically applied to the disc, some tinny cracks occur from several holes. In this study, durability tests under extreme braking conditions were conducted on the dynamometer to observe the crack initiation process in detail. A coupled analysis between heat transfer and thermal stress was also performed by using the general nonlinear 3D FE program. It was found from the durability tests that the surface hardness of the disc decreased since the disc was subjected to the tempering effect due to braking heat. Decrease in hardness makes the disc material weak. Consequently, the thermal stress cyclically exceeded the critical stress causing the cracks around the holes and driving them greater. The stress-strain history of the disc material at the point where a crack initiated, was successively calculated considering the material softening for the brake disc while the decrease in material strength of the brake disc was taken into account for the FE analysis. These results indicated that tensile stress occurred around the holes and fluctuated in correspondence with the heat cycle. Then, cracks initiated and growing around the small holes, were due to cyclic thermal stress in tension, namely thermal fatigue in conjunction with the decrease of yield stress and hardness of the disc material due to heat accumulation.

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This study develops an upper body motion assist system that aims at enabling disabled people with lower limb disability to control their upper body attitude by their own will. The assist system employs a parallel wire mechanism of which the platform is suspended and moved by wires. Parallel mechanisms can arrange the actuators on the base and have advantages such as high power, high speed and high accuracy; they offer other advantages in lightness and body flexibility due to the wire actuating. Thus, they are suitable for the assist system attached to the body. However, as parallel wire mechanisms have multi-degree-of-freedom and redundancy, the analysis of tension applied to the wires to drive their moving platform is difficult. This paper proposes the effective method for evaluating the maximum wire tension induced by external forces in arbitrary-direction; by the eigenvalue analysis with considering the vector-close condition. The method makes it possible to design a parallel wire mechanism to be compact and driven by small force. By using the proposed method, we develop the upper body motion assist system and confirm its availability.

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Bolted joints are widely used in mechanical structures since the disassembly for maintenance is easy without high cost. However, vibration induced loosing due to dynamic loading has been unsolved subject for a long time. We have developed a new type of nut named 'hyper lock nut (HLN), which realizes anti-loosening performance without complicated tightening process and tool. In this study, we have investigated the mechanisms of bolted joint with HLN, and tightening behavior are analyzed by mean of three-dimensional finite element method. Results are compared with the experimental results for HLN. Good qualitative agreement is observed between analytical results and experiments with respect to displacement, tightening force and tightening torque. We found some new aspects and superior points for bolted-joint with HLN than that of standard nuts. It is found that tightening torque of HLN is higher than that of standard. It is also found that the anti-loosening performance can be realized by the thread contact force at the slit region and angular facing on bearing surface. Moreover, by mean of tensile and fatigue experiments, it is concluded that HLN involves sufficient strength in practical use.

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This research developed a simple and high precision method to measure the length of a fatigue crack using an extremely thin ion sputtered metal film based on that the electric resistance of the film changes with the increase of the crack. The electric resistance of a cracked film was calculated by the electrothermal FEM analysis. Based on the FEM analysis results, the relationship between the electric resistance and crack length is expressed by a practical formula. Fatigue crack length measurements for acrylic and metal test specimens were performed on the three-points fatigue test equipment. Based on the good agreements between the measurement results by the ion sputtered film and that by the optical microscope, it is clarified that the crack length measurement method with an ion sputtered metal film has a very high precision. In addition that the measurement system is very simple, this method can be said to have a high practical usability.

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This second paper describes the theoretical modeling of traction coefficient between uncoated paper web and circumferentially grooved steel roller. Extending the prediction model for smooth roller, which was formulated based on the contact mechanics between paper and steel in the first report, the new prediction model for grooved roller is obtained. To confirm the applicability of the model to the prediction of traction coefficient, the predicted results are compared with the measured data for smooth and two kinds of grooved rollers by changing roller velocity, web tension, wrap angle and width. The same test rig as used in the first report is used for the measurements. There are good agreements between the predicted results and measured data for a wide range of test conditions, and the applicability of the prediction model is verified experimentally.

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Characteristics of molecularly thin lubricant films are basically determined by their interactions with solid surfaces. Since these interactions can be modified by engineered microscopic surface textures, it is expected that rational design of the textures will make it possible to attain desired tribological functions and performance. In this research, with the aim of applying it to head-disk interface of hard disk drives, we propose a method based on diffraction simulations that enables thickness measurement of molecularly thin films coated on grooved solid surfaces. Using this method, we experimentally investigate the spreading characteristics of nanometer-thick polymeric liquid lubricant films on grooved surfaces. The results revealed that the average thicknesses of the films dip-coated on the grooved and smooth surfaces under identical conditions were approximately the same, whereas lubricant spreading on grooved surfaces was significantly faster than that on smooth surfaces.

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A new apparatus has been developed for experimental study of basic characteristics of flow electrification phenomenon. Electricity produced on metal wire meshes as liquid flows over them was measured using the apparatus. In order to examine the effects of channel shape and solid-liquid combination, meshes with four different opening areas as well as ones made of four different kinds of metals were tested for machine oil and fluorine compound (FC) a test liquids. The measurements have revealed how the examined physical factors dominate the production of electric charge. The findings are summarized as follows; (1) electric charge produced on the metal mesh increases with an increasing liquid velocity flowing over the mesh. (2) The charge production also depends on the rate of liquid velocity change. In other words, the acceleration of flow is another dominating factor in flow electrification. (3) The longer the perimeter of a mesh is, the larger the produced charge becomes at the same velocity of liquid through the mesh. (4) Machine oil charges brass, copper and stainless steel negative, but aluminum positive, whereas FC charges all these metals positive. In electrification between machine oil and these metals, the amount of charge is the largest for brass, while the smallest for aluminum. FC produces most charge on stainless steel and least on brass and copper.

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This study deals with the machinability of steels after heat treatment with CO₂, laser using h-BN powder and blast furnace slug as absorbent. h-BN is well known as solid lubricant. As for blast furnace slug, its composition is similar to that of inclusions in calcium dioxide steel that shows good machinability. The absorbance of slug and h-BN were more than 80%, so it is said that these powders can be used as absorbent for CO₂, laser. Only in the case of h-BN, absorbent was melted into substrate and its depth was about 200 μm. When turning the steels after laser heat treatment using h-BN power and blast furnace slug as absorbent, carbide tool showed smaller tool wear than the case of carbon type absorbent. In the profile of the machined surface, there was a wave of about 5 μm in amplitude and its wavelength was equal to the feed rate of laser in heat treatment. This is because the workpiece surface after laser heat treatment has a periodic distribution in hardness. The hardness in the surface layer of workpiece was higher than that of the substrate.

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It is known that in dry cutting, temperatures of both work piece and tool will be raised, the work piece softened and therefore cutting resistance decreased. Meanwhile, the tool life will be short and the accuracy of the work piece lower. On the other hand, in wet cutting, temperature changes of both work piece and tool are restrained, the tool life will be a little bit longer and the accuracy will be higher. However, due to the work piece cooling, softening phenomenon of the work piece is restrained resulting in higher cutting resistance in wet cutting in comparison with that in dry one. If the tool is separately be cooled and the work piece is also separately be heated and softened, the softened work piece can be machined by tool with maintained hardness. Therefore the cutting resistance will be very small and the tool life is very long. In this study, both the cooling system of the ball end-mill and the heating system of the cemented carbide work piece were equipped. The ball end-mill was made from the electro-deposited diamond which has function of heat pipe in its body. Materials of the work pieces were SKD11, SKD61 and V10. These work pieces were heated from 373 K to 573 K by an infrared radiation heater. The optimum machining conditions were investigated in some experiments. Then surface roughness, hardness changes of the work piece and the tool life were measured and evaluated. It is concluded from the results that; (1) The cutting resistance was reduced thanks to the softening of the work piece. (2) Tool's temperature changes created by work piece pre-heating process and by heat source generated during cutting duration were restrained by the heat pipe function of the ball end-mill. (3) This system allows to achieve work piece softening and tool's hardness and strength maintenance simultaneously.

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About 100 years ago, Dr. Franz Reuleaux invented the elliptical chuck which made it possible to cut elliptical cylinder in the same as cutting cylinder. This was invented on basis of turning block double slider crank mechanism. For this reason, this chuck had a problem of causing vibration as the rotational speed increased. Therefore, this mechanism could not been put into practical use. In order to overcome this weak point, one of the authors invented a new type of cutting machine for elliptical cylinder. In this paper, first the principle of new cutting machine is described. Next this machine is designed and made for trial. Finally two elliptical cylinders are made for trial and measured by roundness tester. Experiments prove that the principle of the new cutting machine holds true, principle of mechanism of cutting elliptical cylinder, and shows fundamental characteristics of this machine and its possibility for practical utility.

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It is called for that development of the efficient production system in large variety and small volume manufacturing carries out simultaneous solution of the complicated demand of a product kind, quality, cost, and delivery. Since only the person experienced in development of a production system can carry out subject solution, modeling of the production system which is economical by general purpose large variety and small volume production has not been completed. In order to solve these subjects, the product application is limited first, and a functional module is defined paying attention to the product function of the product and a product design and the modularized design of the manufacturing process are performed. This production system consist of function quality completed production which completes the functional quality which used this process module as the base is performed and the mixed and synchronized production system or the demand synchronized novel production system. The wide variety and small volume production system by which the knowhow of a production systems configuration corresponded to quality, cost, and delivery flexibly with constituting a module hierarchical at least can be offered.

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The concept of Anthropocentric Cell Manufacturing System (ALMS) is relevant to skill enhancement rather than skill replacement. Thus, this approach ACMS consists of scheduling system, post on-the-job training (OJT) system and safety system. However, efficiency of the best ACMS scheduling still depends on how to allocate skilled engineers on the appropriate jobs. In this paper, we described the scheduling based on skill level or attitude of engineers. The matching of equivalent skill level evaluation and genetic algorithms, a scheduling method was used as job and engineer characteristics evaluating, job based cell resources for encoding a bit string of chromosomes. The main contributions are evaluation of equivalent skill levels of engineers on each job by their supervisors and selection of machine models based on capabilities of engineers on that. The results showed that the equivalent skill levels of engineers on each job depended on job characteristics and the scheduling by this method was presented through the gantt-chart. This new approach of ACMS scheduling will be practically to achieve the highest production efficiency in cell manufacturing by putting a right man on a right job at right time.

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In this paper, we consider a selective scheduling problem of minimizing a due date involving criterion for a single uncapacitated vehicle.Let G= (V, E) be a path with a set V= {υ_i|i=1, 2, …, n} of vertices and a set E= {{υ_i, υ_i+1} |i=1, 2, …, n-1} of edges. The vehicle is initially situated at υ_i. There is a job i at each vertex υi∈V, which has its own handling time h_i and due date d_i. Travel times ω_{i, i+1} of the vehicle are associated with edges {υ_i, υ_i+1} ∈ E. A schedule of the vehicle is called 1-way if it visits every edge {υ_i, υ_i+1} exactly once, that is, it simply moves from υ₁ to υ_n on G. In this paper, the vehicle is assumed to move according to a 1-way schedule. But a choice still remains for each job whether it is processed at the time of the visit, since a certain penalty a (_??_1) is required if some job is not processed by the vehicle. If a processed job i is completed by its due date d_i, no penalty is required. Otherwise, the unit penalty is paid. The objective is to minimize the total penalty over all n jobs. We show that, if a is given as a positive integer, the selective vehicle scheduling problem can be solved in polynomial time by a dynamic programming approach.

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Logistics optimization has been noted increasingly as a key issue to improve the business efficiency under global competition. So far studies have concerned with the simply formulated problems and major emphasizes have been paid to developing a new algorithm, and to evaluating its validity through benchmarking. Since easy application often causes a dramatic increase in problem size, and hence in such difficulty that makes impossible to solve the resulting problem by any currently available software, we need to make more earnest efforts to cope with the complex and complicated real-world situations. In this study, we concern with the hierarchical logistic network from two aspects that have been scarcely considered previously though they are very popular in realworld. We consider there a multi-kinds product problem and a problem with stair-wise discount cost of transportation. To cope with these conditions, we have developed extended methods of the hybrid meta-heuristic approach for each problem. Novel iterative procedures are invented respectively while keep applying the graph algorithm for the high speed solution of the lower level problem. Validity of the former method is verified through comparison with the commercial software. For the later method, we implement the algorithm as software amenable for supporting a daily logistic planning, and confirm its effectiveness through a real-life application.

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We propose a new type of mock-up consisting of a transparent solid object, fabricated by stereolithography, with a small video camera embedded inside. By processing the video image of the object surface taken from the inside in real time, operation data of the mock-up (e.g., when interfaces such as buttons and dials are operated by the users) and usage (e.g., which hand and fingers are used to operate the buttons and dials of the mock-up) data can be obtained. Consequently, a simple stereolithography model without sensors or circuits can be a functional mock-up. By analyzing these automatically obtained usage data, operation data and the result of functional simulation, some usability data will be obtained or extracted. Designers can use such data to improve the usability of the product that the mock-up imitates. The feasibility and validity of the concept is confirmed and reported on the basis of three experiments.

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This paper propose the concept of hidden problem visualization and measures method in design stage with system DRBFM (Design Review Based on Failure Mode). The potential problem in the design stage involves unnoticed problems and misunderstood problems. The unnoticed problem can be visualized by the work flow of system DRBFM which takes into account the hierarchical structure of products. The misunderstood problems is also visualized by discussions in system DRBFM, containing the collation of concerning design with Design Regulation and the verification by Professional adviser based on Attention in operation. Afterwards, the total of misunderstanding problems reflects in improvement of Attention in operation. By the above concept, system DRBFM can posess two functions. The one is as for the useful tool of OJT (On the Job Training) which educates designer who has misunderstood or oversighted immediately by Professional adviser. The other is the construction of precationary measures organization with system DRBFM, Professional adviser, Design Regulation and its Attention in operation. To display the use of thease functions, the proposed concept is applied to design change of hair drier. The application example can display the role of all part of system DRBFM intelligibly.

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In the design of an electromagnetic circuit for a solenoid actuator, CAE tools such as a simulation software package based on FEM or BEM electromagnetic field analysis are utilized to attain accurate design information. First, a designer empirically determines the initial dimensions of the solenoid during the first simulation trial, and then attempts to optimize them by trial-and-error iteration. However, CAE tools are usually cumbersome to use in this iteration stage. The time consumed during the trial-and-error iteration can be reduced and the design process can become more efficient if the designer can obtain information about the optimum initial dimensions before starting the simulation. This paper aims to develop a pre-process that can provide a designer with roughly-optimized solenoid dimensions as an initial input model for a CAE tool. The rapid optimization process is presented from the viewpoint of both economy and compactness.

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