The conventional pressure change method used in leakage tests is sensitive to the ambient temperature variation. We propose a new method using Adaptive Filter with RLS algorithm to compensate for temperature variation in pressure change leakage detection. In the proposed method, the relationship between the pressure in the target vessel and the temperature signal measured by the temperature sensor installed near the target vessel will be adaptively estimated and the temperature-dependent factor in the pressure change will be subtracted from the pressure signal. In this paper, we present the principle of the proposed method and the validity of proposed method is verified by numerical simulation.

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Currently, about 60% people of the whole world are living in masonry structured residences. These areas partially belong to developing countries with frequently occurred earthquakes. There are numerous brittleness buildings as non-engineered structures in the countries. Therefore, buildings were collapsed when an earthquake occurred, with continuous human damage occurs. The purpose of this study is developing simple and low cost health monitoring sensor system, using a piezoelectric film. Our failure prediction system aimed at avoiding human suffering caused by buildings collapse at an earthquake. Our novel sensors comprise a glass pipe that ware directly installed in brick masonry specimens or a holder with a glass pipe containing piezoelectric film elements for measuring signals during static loading tests. For this purpose, brick masonry specimens were subjected to compression test to evaluate their mechanical properties and to investigate proposed sensor response. The comparison results of measurements with piezoelectric limit sensors show that sensors responded before and during broken of brick masonry specimens. We regard the applicability of new piezoelectric limit sensor to detect premonitory failure obtained using the static loading test.

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In this work, we apply the sensor-network technology to the livestock industry. We concentrate on sensing of odors of livestock, such as ammonia. We distribute several nodes to the farm where livestock is raised, and send odor data to server, and enable the farmer to access to the data through the network, As a prototype, we implemented a circuit to save the odor data to SD card, and confirmed that the odor of ethanol was detected. We will make the data accessible from the network.

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In order to numerically simulate the formation of hologram appearing in the in-line holography method with high precision, improvement for FDTD (2,4) method was proposed. Examination about the effect of improvement showed that proposed improvement remarkably suppress the phase error of electro-magnetic wave to negligible level even in the case where large-scale calculation domain is ordered to treat multiple scattering problems, while the ordinal FDTD (2,4) method causes serious error in such cases. In addition, Dey-Mittra method, which is one of the conformal FDTD methods, is combined with the above-mentioned FDTD (2,4) method with improvement in order to suppress the error associated with step-wise approximation of particle shape. At the next stage, examinations were carried out using the above-mentioned conformal FDTD (2,4) method, about the influence of closeness between two particles on the location error of reconstructed image in the in-line holography method. Results of numerical simulation showed that reconstructed images of particles are deformed when the distance between two particles is shortened, and error appears in the evaluation of particle location- Location error is decreased with elongation of distance between two particles when they go away in the perpendicular direction to incident beam. On the other hand, contrary tendency partly appears when two particles go away in the parallel direction with incident beam.

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This paper introduces a new method to analyze the response of the multiple supported nonlinear systems. There are many papers about the response analysis of a system having nonlinear properties, such as friction or elastic-plastic characteristic. However, most of them are about the one input system because it seems difficult to apply more than one input. Although a simple method for estimating the multi-input response analysis for linear systems is also proposed, they cannot use for nonlinear systems. In recent years, the importance of seismic design considering both nonlinear and multi-input problems has been focused. Therefore, we propose a method to estimate the maximum response of multi-input system with elastic-plastic characteristic for rationalization and high evaluation of seismic design of piping systems in the present study. The estimated results are compared with simulated value by numerical time history and showed the effectiveness of our method.

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The crossover piping is installed between seismically isolated and non-isolated building; the reactor building (RB) is only isolated using seismic isolation systems whereas the turbine building (TB) is non-isolated. The crossover piping supported by both isolated and non-isolated building is deformed by large relative displacement between the two buildings. The flexible structure is required for crossover piping which allows the relative displacement. It also has to endure the seismic response of itself caused by different seismic excitations from both buildings. The seismic design for crossover piping needs evaluation considering both of the relative displacement and the seismic response. In this study, the results of shaking table tests of 1/10 scaled Main Steam (MS) piping model has been used to compare the seismic response analysis of crossover piping. Based on the results of shaking table tests and the analyses, the seismic design method for crossover piping is proposed.

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According to investigations of several nuclear power plants (NPPs) hit by actual seismic events and a number of experimental researches on the failure behavior of piping systems under seismic loads, it is recognized that piping systems used in NPPs include a large seismic safety margin until boundary failure. Since the stress assessment based on the elastic analysis does not reflect actual seismic capacity of piping systems including plastic region, it is necessary to develop a rational procedures to estimate the elastic-plastic behavior of piping systems under a large seismic load. With the aim of establishing a procedure that takes into account the elastic-plastic behavior effect in the seismic safety estimation of nuclear piping systems, a task force activity has been planned. Through the activity, the authors intend to establish guidelines to estimate the elastic-plastic behavior of piping systems rationally and conservatively, and to provide new rational seismic safety criteria taking the effect of elastic-plastic behavior into account. As the first step of making out the analysis guideline, benchmark analyses are conducted for a pipe element test and a piping system test. In this paper, the outline of the research activity and the preliminary results of benchmark analyses are described.

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We carried out operational transfer path analysis using addisional mass for a structure subjected to floor vibration to identify a transfer path from the floor to an evaluation point via a support. The contribution of transfer path between the evaluation point and three supports was respectively investigated and the support with largest contribution was identified. We could reduce peek amplitude of evaluation point by anti-vibrational measure where a spring constant of the identified support was made small. Effectiveness of the operational transfer path analysis using additional mass was demonstrated.

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The impact damper consists of an impactor, a container, and walls. It is strongly non-linear. Many studies have been dedicated to analytical researches. In this paper, the authors applied the case of only two impactors which are main component of an impact damper and pay attention to setting ways of containers which enclose two impactors. They regard the structure model that has two floors as primary system. They examine the setting way with the maximum damping effect from the viewpoint of energy of primary system by performing shaking test for the structure model. Then, they examine whether the setting way with the maximum damping effect is dependent on coefficient of restitution, mass of impactors, and input acceleration. As a result of experiments, when the coefficient of restitution is close to 1 and mass ratio is close to 0.25, the case of installing two containers in parallel has the maximum damping effect. Furthermore, the result doesn't change if response changes.

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Magnetorheological elastomers (MREs) are class of smart materials whose rheological or viscoelastic properties can be varied by applying external magnetic fluid. MREs are the solid analogues of MRFs and expected to overcome the disadvantages of the fluid such as the particle deposition and the sealing problems. When such MREs are exposed to external magnetic field, the strength of the inter-particle force will change and thus their apparent elastic modulus is changed depending on the magnitude of the field. In this paper, the stiffness controllable elastomer composites known as MREs are first fabricated and their field- dependent dynamic properties are tested. The MREs are then applied to the vibration isolating mounts along with variable stiffness control scheme. Experimental investigations show that the vibration of 1-dof structure can be reduced by the proposed anti-vibration mount with variable stiffness property.

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This paper explores the response of a damper using particle assemblage to impact force. We measured the displacement and resistance force of the damper. The impact force was made from the fall of the weight. The displacement of the damper was influenced by packing fraction of the particles. But the resistance force of the damper was not influenced by packing fraction of the particles.

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The displacement and crossing angles changes in the S-curved grooves design, which increases the dampening performance. Under seismic vibration test, expected results were confirmed. Therefore, design optimization was conducted using theoretical analysis. Based on the analysis result, the response displacement was reduced to 14cm under JMA Kobe seismic wave 100%, which is smaller than traditional response displacement of 20cm.

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A lot of seismic damages of hanging type mechanical structure in industrial facilities were occurred in Great East Japan Earthquake, and the industrial functions stopped at many facilities. Moreover, fallen damage of mechanical structures from a hanging in architectural structure and the falling off of some elements in mechanical structures caused a secondary damage such as severed evacuation route. This study has been carried out to upgrade the seismic safety improvement of hanging type mechanical structure in several industrial and plant facilities from analytical and experimental approaches. In this paper, the experimental result in shaking table test is shown to investigate fallen mechanism of hanging type mechanical structure, and analytical results using nonlinear model with hysteresis damping is described. Furthermore, the evaluation of damage mechanism based on low cycle fatigue damage is conducted.

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In various industrial plants such as thermal power plants, nuclear power plants or chemical plants, many cable trays are generally used for supporting cables by which control signals will be transmitted. Cable trays are generally made by thin steel plates both sides of which are folded in the vertical direction, while cables are simply placed on the tray. Thus, cables begin to slide when the response acceleration of trays exceeds some amount of value. Consequently, seismic responses of cable tray will also depend on the occurrence of sliding motion of cables. And cable trays reveal torsion bending because sides of them are folded in the vertical direction and thus the shear center differs from the mass center. Therefore, cable trays are seen as highly nonlinear structural systems. In this study, seismic responses of the cable tray are investigated analytically considering the cable sliding motions. A cable tray is modeled by a two-degree-of-freedom system. Response acceleration and displacement of the tray and the cable are evaluated for seismic inputs. It is confirmed that the sliding motion of the cable has very large influences on the seismic responses of the cable tray.

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The elastic vibration of a railway carbody influences a riding quality, and vibration reduction is required. The first mode of the elastic vibration of the carbody can be reduced by using dynamic vibration absorber (DVA) effect utilizing bogie-carbody dynamic interaction proposed in the previous paper. On the other hand, vibration increases in high frequency range. In this paper, the damper having frequency dependent characteristic is proposed to reduce the elastic vibration of the carbody in high frequency range. It has high damping in low frequency range to get DVA effect, and low damping in high frequency range to obtain the isolation effect for input from the truck. A prototype damper having plastic valve as like an orifice is manufactured. The sectional area of the orifice is varied by velocity of the piston, and damping characteristic can be switched in high frequency range. In order to estimate the damping coefficient, vibration test is carried out. Finally, dynamic characteristic of the damper is investigated experimentally.

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The rocking vibration with friction is focused in this study. The fell down conditions of the rocking system with friction are clarified. Rocking vibration is the rotational motion around the both ends of the structure and occurs when the structure is excited. In this report, the behavior of a single-degree-of-freedom rocking system with friction is taken into consideration. An analysis model is proposed and the response is calculated in the case that the structure is excited by sinusoidal wave and seismic wave. In order to estimate the parameters to prevent the fall down in a simple manner, two state judgement maps are proposed. One is the "Input variation model" focusing on the parameters of input sinusoidal wave and the other is the "Form variation model" focusing on the parameters of the structure form. From the analysis results, it was possible to clarify the basic characteristics of the rocking vibration with friction from the aspect of the input waves and the dimensions of the structure.

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Behavior of the self-standing structure on the ground under sinusoidal excitation in horizontal direction is investigated. The nonlinearities of rocking motion and sliding motion and the impact between base and structure are considered to examine this behavior. The analytical model is composed of a rigid block for simplification. The relationship between the amplitude of vibration acceleration and the excitation frequency is investigated, in addition to that between the amplitude of vibration acceleration and friction coefficient. It is found that the maximum rocking angle depends on frequency of input wave, and the maximum sliding displacement becomes large when the input wave has large acceleration in a long period region. In addition the rocking angle tends to decrease due to occurrence of sliding motion. Therefore, it is said that rocking and sliding motion should be suppressed simultaneously.

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The authors propose a small isolation table with coil springs and roller bearings in order to obtain a vibration isolation table which is simple in construction, low cost and effects of seismic isolation. The table board is supported by four legs with roller bearings, and connected by four coil springs to the base plate. The table is able to move smoothly any horizontal direction. A sliding type friction damper is also installed beside the legs for suppress the resonance of the isolation table under strong long period components. The trial isolation table is manufactured, and resisting force characteristics are measured. Next, seismic vibration tests are carried out using a shaking table. Response acceleration and displacement are measured when earthquake which has a strong long period component are inputted, and the experimental results are compared with the calculated results. Finally, the effect of seismic isolation and the propriety of the calculation are confirmed.

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This paper deals with the design method of a thin plate structure with a fixed end and a contact area in consideration of the contact state under vibration. The boundary condition of a cantilever beam with a contact area depends on the contact force at a contact area. Therefore, it is necessary to consider the vibration characteristic with a contact condition in the case that the beam is designed. In the previous study, the authors proposed the finite element model of the beam with a contact area which is described as two-dimensional beam element. However, the detailed model of a contact area is needed for estimation of response of the beam under vibration. In this study, the simple design method of beam with a contact condition is investigated. Firstly, the finite element model of the beam with a contact area which is described as non-linear spring element based on Hertz theory of elastic contact. Secondly, the comparison of the response between the result of numerical simulation using the FE model of the beam and vibration test is shown. The numerical simulation using the FE model can be useful for obtaining contact condition without vibration test.

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The particle velocity of excitation source is necessary to measure the transfer function of the sound field. Therefore we connect acoustic duct to the sound field and use 2-microphone measure technique that calculates the particle velocity of boundary by two points of sound pressure. Precondition of 2-microphone measure technique is that plane wave is transmitted in acoustic duct. However, the situation that the sound pressure on the boundary is not plane wave is thought about depending on a state of the sound pressure distribution of the sound field. In this study, we analyzed a connected sound field model. When node of the particle velocity emerge on boundary, we cannot be obtained a correct result by experiment. Calculated result agreed with experiment and we showed a condition particle velocity on boundary is not plane wave.

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Internal noise detected by passengers inside of the cabin of a car or an aircraft is caused by coupling vibration between the structure and the internal sound field. For practical purpose, it is most efficient to suppress the structural mode associated with acoustic dominant mode in order to reduce noise level in the cabin. Therefore, it would be beneficial to find the structure dominant mode. In this report, first, we suggested the determination technique for acoustic or structure dominant mode in the coupled system. Furthermore, in order to identify natural modes precisely, we examined experimental methods for frequency response measurement and modal parameter identification methods for the coupled system. This study proposes a determination technique for the natural mode of the coupled system. The validity of the proposed method is examined through the numerical simulation. In addition, the effectiveness of the multi-point excitation and acoustic excitation for the coupled system is illustrated.

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As one of the way saving energy of vessels, effective use of exhaust heat is described in this study. Recent years, the depletion of fossil fuels, air pollution by exhaust gas has become a serious problem. Therefore, the technologies about fuel saving and effective use of energy are required. Vessels also use fossil fuel as an energy source. Large vessels generate steam in the exhaust gas economizer by using the exhaust heat of the main engine. This steam is used for heating fuel, heating the room and hot water supply in the vessel. But, recovery of exhaust heat of the main engine is not enough. If it is possible to generate electric power using the low-pressure steam, that can contribute to energy saving of vessels. Therefore, prototype steam engine for generation using low-pressure steam is developed. This new steam engine is use the end cam which is newly devised as a transformation of motion mechanism. In this paper, this new cam called crown cam. Prototype steam engine was tested. At this time, valve opening and valve timing was changed to evaluate the effects on performance of steam engine. First, the principle of operation and the structure of prototype steam engine are introduced. Secondly, this engine is tested by low-pressure compressed-air. Finally, test result of the prototype steam engine is described.

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Normally, high viscosity fluids are mixed in a batch mixer. However, the mixed fluids tend to be non-uniform mixing. We have therefore developed a small mixer which has a mixing area in millimeter order. A new mixing method for small mixers is described in the paper. This mixer mixes two flowing fluids by vibrating the wall of the flow channel using linkage mechanism operated by a DC motor. The mixing process was observed under an optical microscope fitted with a CCD camera. High viscosity fluids were prepared by adding thickening agents to water. We determined the optimal mixing state by mixing fluids of two colors (red and green). The mixing performance was evaluated under varying flow rate, the viscosity of the fluid, and vibrational frequency. As the results, we confirmed that when setting flow rate to low level and frequency to high level, the mixer provided better performance.

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Recently, earthquakes frequently occur in Japan. In order to protect people from earthquakes, it is necessary to promote seismic isolation devices. The penetration of the devices is late in attached houses, because the devices are very expensive. We must develop a low-cost seismic isolation device for detached houses. We suggested a new seismic isolation device which uses a two-layer circular tube. If the inner layer contacts with the outer layer under lateral compression load, hysteresis is produced in the tube. We think that the tube can have energy absorbing capacity. It is known from previous studies that hysteresis occurs in the tube using by experiments. However, the tubes used in the device are referred to as either clearance fit tubes or interference fit tubes in the process of manufacturing. In this paper, we have clarified a relation between the fit and hysteresis loss using by experiments. As a result, hysteresis loss changes depending on the fit. Hysteresis loss of the interference fit tube is larger than the clearance fit tube.

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In this study, we device how to measure preload of the cross roller bearing and reveal the influence of preload on function torque. In addition, we look at the effect grease filled the class roller bearing with on friction torque. One of the most important problem is reducing friction torque of the cross roller bearing. Hence, we are demanded for saving energy of machine to solve this problem. The cross roller bearing have high stiffness and rotation accuracy, however it have larger friction torque than other bearings. For this reason, design policy of giving preload to the cross roller bearing is required. We measure preload of the cross roller bearing by new contrived equipment, and test condition is tightening torque of fixing the cross roller bearing by bolts. We measure friction torque.by test machine, and test conditions are preload, rotational frequency of inner ring, and radial load. In conclusion, preload is a small influence on friction torque. Additionally, large consistency and high kinetic viscosity grease has an effect on reducing friction torque.

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With the speed reducing device, downsizing and cost reduction has been required strongly. In this report, we added the tapered roller bearing for supporting the gear output shaft to deceleration function as a traction drive. We ensure the necessary reduction ratio by this method, and propose a method to downsizing. In addition, by using a tapered roller bearing, compared to other hybrid reduction device, torque capacity was increased. In this study, we calculated the torque transmitted by the decelerating bearing which receives the gear reaction force, and designed the dedicated output shaft integrated retainer. Furthermore we performed the test operation and examined the reduction ratio, the mechanical efficiency of power transmission and the slip ratio. Here, the maximum target transmission torque was 20Nm and the maximum rotation speed was 200rpm. In this study, we used the output shaft integrated retainer that materials of contact surface were PBC, PEEK and Silver-plated SCM steel, and compared the three. When using the PBC, it confirmed that it can decelerate as designed, and achieved 20Nm of the target torque at 1200N or more. Maximum power transfer efficiency was 81.8% at the 1200N.

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In order to improve vibration characteristics of reciprocating compressor with labyrinth piston, we investigate reaction force and sealing characteristics of piston-cylinder system using modeled experimental equipment. As supply pressure increases, stiffness, damping and flow rate increase in all case. As clearance between the piston and the cylinder decreases, stiffness and damping increase and flow rate decreases in all case. The stiffness and the damping of system with labyrinth piston is smaller than those with plane piston which has no labyrinth. On the other hand, leakage of labyrinth piston system is smaller than that of plane piston system.

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Internal combustion engines have been required for further improvement of thermal efficiency, i.e. reduction of fuel consumption. While downsizing turbo engines are often mentioned as the trend in recent years, cylinder pressure has been increasing and engines are becoming compact and light weight. Because of this, the engine components have become narrower and thinner-walled, and local lubrication performance in sliding parts is continuously increasing due to high pressure and partial contact. Appropriate calculation conditions and also the verification of the calculation results by the precise measuring method have been required. However, calculated results in sliding surface with deformation in engine operating condition have not yet been confirmed experimentally. The optimization of the multi-layer form a film of the sensor shape and sensor film was performed in order to reduce the temperature sensitivity and the strain sensitivity is a measurement error of the oil film pressure.

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For mechanical friction loss reduction, the specific pressure of sliding parts or contact surfaces is increasing. For this reason, the problem of wear and damage has occurred according to change to worse of lubrication condition. In order to solve this phenomenon, it is important to get to know temperature distribution, and the sensor which measures temperature, such as machine sliding surfaces and a contact surface, with high precision is needed. This research described the feature of each material from comparison of the form and pressure sensitivity of a thin film type temperature sensor, or temperature sensitivity which used platinum and titanium. Moreover, the example of formation to the gear tooth flank was shown as an example of attachment of a sensor.

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vUsing the characteristics of temperature dependence of liquid viscosity, possibility of control and improvement of static characteristics of hydrodynamic bearings is examined numerically. The simplified thermohydrodynamic lubrication (THL) model based on the Reynolds equation on the assumption of constant viscosity across the film is derived. The calculation is performed for inclined plane and tapered land bearings. The bearing geometry and temperature distributions are given by the parameters. When the inlet zone of the bearings is relatively cooled, the hydrodynamic pressure becomes high, the load-carrying capacity increases, and the friction coefficient decreases, but the side leakage hardly changes. The behaviors may contribute to enhance the static characteristics of hydrodynamic bearings.

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As well as in computer programming, both declarative and procedural methods should be available in industrial product design. However, design for additive manufacturing is mostly based on declarative CAD as well as other areas of product design. This presentation reviews a conventional procedural method for CNC and proposes a procedural design method for 3D printing.

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"Quality engineering" is technique to take a technology development and research effectively. It is called that the "Taguchi Methods" is named after Dr. Gennichi Taguchi who is the designer. The parameter design is a method to carry out an experiment effectively and evaluate dispersion of the quality. It is the design method to optimize the function of the system. Therefore, it may be said that it is methodology the standard of the parameter is applied statistically to decide. In this report in the collaborative research with business partner, lectured about the example that practiced the optimization of the press fit process of the general-purpose motor axis by an application of this technique.

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Decoration films and shrink films are utilized to improve designability of injection molding products. Such films are shrunken and stretched in injection process so that the design pattern represented on the films has deformation. In this study, a method to correct the design pattern is proposed in order to cancel the design pattern deformation by shrinking and stretching. The effectiveness of the proposed method is confirmed by experiments.

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Small and medium enterprises are working on original product development in the field which is a niche based on original technology in a manufacturing enterprise. High technical power is requested because a medium sized enterprise which doesn't belong to large enterprise that is working on product development in the business field certain limited. Therefore, in order to promote the product charming for a customer and product development based on creative technology for a proprietor, the management is requested high level of the technological management. In this paper, it is an object to classify a management element about technological management in a core manufacturing enterprise, and proposes quantitative evaluation method and makes the validity clear based on a case. Five elements of management is proposed by this paper, which includes consisted of three elements of conventional management, "people", "goods" and "money (capital)" and also added two elements, "information" and "outward activities" that can correspond to an information-oriented society and globalized circle. The evaluation system of technological management of a manufacturing enterprise is also proposed to set up the evaluation item every hierarchy, settled on the item which has an influence on five elements of management that becomes the root of technological management.

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This paper deals with the influence of water-soluble cutting fluid on tool life (flank wear) of various coated cutting tools and finished surface roughness compared with dry cutting and water-insoluble cutting oil in hobbing. Experiments were conducted by simulating hobbing by fly tool cutting on a milling machine. The following results were clarified. (1) In the conditions of 1-thread and 3-thread hobs, the water-soluble cutting fluid used in the tests prolongs the tool life of TiSiN- and AlCrSiN-coated tools compared with that obtained with dry cutting and the water-insoluble cutting oil. (2) The water-soluble cutting fluid used in the tests is effective for all of various coated tools in the term of finished surface roughness. (3) From the viewpoints of tool life and finished surface roughness, the water-soluble cutting fluid is suitable for TiSiN- and AlCrSiN-coated tools.

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CFRP (Carbon Fiber Reinforced Plastics) has been used for airplanes and automobiles for the purpose of light-weighting. However, it is well known that CFRP is a difficult-to-cut material because of increasing tool wear dramatically and showing inferior finished surface quality. This paper presents the influence of various water-soluble cutting fluids on tool life and finished surface roughness in end milling of CFRP. As a result, (1) Water-soluble cutting fluids, emulsion, soluble and solution, used in the tests improves the tool life compared with dry cutting. Especially, the difference of tool life is remarkable at the high cutting speed of 171 m/min. (2) When using a fluid, in which 0.2 Vol% of rust preventive agent added to water, showed the almost the same cutting performance as the water-soluble cutting fluids used in the tests. It was suggested that the cooling ability is to be involved with tool wear in cutting CFRP. (3) The finished surface roughness is small at the high cutting speed. There is no difference in surface roughness obtained with the water-soluble cutting fluids used in the tests.

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The performance of wire-sawing of rock in vacuum has been investigated for future lunar and planetary explorations. The machining amount was decreased with a decrease of the vacuum pressure. Nickel to fix diamond grits on a core wire adhered on a rock specimen in vacuum and the rock was hardly cut in the end. In this report, the slicing performance was tested with various saw wires. The machining depth was increased with an increase of feeding speed of the saw wire in air. The machining depth in vacuum, however, did not depend on the feeding speed. The exposure of the grits from the electroplated nickel, large gripping force of the grits and increasing the pressure due to the low grit density increased machining depth.

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As the substrates of semiconductor devices, silicon wafers are required to have extremely high surface flatness for increasing the integration density of the devices. In particular, edge roll-off, which seriously deteriorates the surface flatness near the wafer edge during polishing process as the final stage of the wafer manufacturing, is strongly required to be suppressed. In this study, we investigated the properties of polishing pad required for decreasing edge roll-off using finite element structural analysis and, as a result, it was found that polishing pad with small thickness and small deformation could improve the surface flatness near the wafer edge. Also, we investigated the influence of measurement conditions in indentation test on measured deformation property of polishing pad through the indentation test for different types of polishing pads. On the basis of the investigation, we proposed the evaluation method of deformation property of polishing pad for estimating the obtained edge surface flatness.

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Various kinds of polishing pads have been utilized for polishing glasses, Si wafers, etc. In this paper, authors focus on the pumping effect of slurry in the pores of polishing pads. For improving the pumping effect of slurry, the vertical hole-structure pads were developed, which were made by epoxy resin. It was known that fluorine treatment on the inner wall of vertical holes could improve the pumping effect of slurry and raise removal rate of workpiece. Comparing to the nonwoven fabric polishing pad impregnated urethane or epoxy resin, the 2-step impregnated nonwoven fabric pad can improve the pumping effect of slurry and raise the number of polishing abrasive grains greatly. As the result, it was clarified that the polishing characteristics of pads are influenced by the pumping effect of slurry.

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In this paper, we examined the processing characteristics of the cast iron plate and the urethane resin porous polishing pads. The similarities between the cast iron lapping plate and the porous urethane resin polishing pad are described. It was known that the conditioning state of tool surface affects the processing characteristics greatly. To improve the performance of conventional tools, we developed the metallic fiber lapping tools and the epoxy resin pads. The metallic fiber tool can grip the abrasives on the lapping area with microasperity. The epoxy resin polishing pad showed higher removal rate and lower surface roughness than a conventional urethane resin polishing pad, because of high hydrophilic property.

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In this paper, an evaluation method of wire bonding state by thin AE sensor is presented. Recommended getting AE signal close to connected area, but conventional AE sensors have drawback installing in vicinity of a connecting area due to spaces or heat-resistance. The AE sensor is 1 mm thick and has greater heat-resistance than them. This make it possible to install the AE sensor to near the connecting area. And it can also get AE signal as a high S/N ratio during a bonding. As a first step, an effectiveness of the AE sensor to evaluate a connecting state is confirmed. Shift conditions from default and consider that the AE sensor of recognizing alteration with AE signal processing in order to find out data included AE signals. As evaluation approach, we used the Mahalanobis-Taguchi method which is used in quality engineering. Consider sample set in a default condition to be a unit space and confirm the similarity of test samples in shifted conditions with figuring out the Mahalanobis distances of test samples. According to variation range, Mahalanobis distance increased and the effectiveness of the AE sensor was confirmed. A relevance between Mahalanobis distance and strength evaluation by pull test was also presented.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades strength of structure. The authors have proposed a reduction method for residual stress using vibration during welding and applied to welding of thin plates. Residual stress is more reduced when larger amplitude of vibration is used. In this paper, repair welding of mold is considered and surface of a thick plate is welded. Two ultrasonic vibrations are used to get large amplitude and reduction of residual stress is examined. Residual stress is more reduced than using one ultrasonic vibration. It is well known fact that residual stresses are statistically distributed. 3 specimens are made for the same condition. Using experimental data, distribution of residual stresses is evaluated by analysis of variance. It is found that difference of distribution of residual stress of each specimen and those of all specimens is small. By t test, it is demonstrated that the method using two ultrasonic vibrations is more effective than that using one ultrasonic vibration for reduction of residual stress.

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Magnetic field assisted machining uses particle brush formed along a line of magnetic force as a tool. By magnetic force, particle brush gives processing pressure to the surface, and it removes the surface by relative motion between surface and particle brush. And, it has been clarified that electrolyzed reducing water can be used as substitutive cleaning solvent for chemical cleaning solvent. The purpose of this study is to establish precision machining technology which combined the physical removal action by magnetic field assisted machining method with the chemical action by electrolyzed reducing water. In this paper, surface finishing was carried out. Then, effect of grain concentration was examined experimentally. Experimental results are as follows: (1) In initial processing step, removal rate lowers, when grain concentration is low. However, removal rate is improved, after hard layer in the surface was removed, and then, effect of grain concentration on removal rate decreases. (2) Effect of grain concentration on surface roughness of finished surface is small.

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In vertical grinding method, largest grinding force, namely normal grinding force is induced along grinding wheel axis, so that high grinding system stiffness is effective for machining accuracy, then the face grinding method is widely used in the production field. In this study, the grinding force distribution which has a pressure dimension, is both theoretically and experimentally analyzed with cup type electroplated diamond grinding wheel. Furthermore, stock removal and residual stock, which are front edge of the wheel generated, is measured and analyzed with ground surface profile. From those analysis, the grinding force distributions are obtained by consecutive difference method of the grinding force variations, and it has a single peak at the internal contact region with workpiece. In size generation process, the grinding amount is almost half of the real setting depth of cut. Almost half of the residual stock is remained due to the elastic deformation of both the grinding wheel support system and the workpiece holding system.

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Many concrete structures have been built half a century ago in Japan. Those service lives are going to pass. So development of efficient and economical testing methods is desired. Climbing testing machine is one of the methods. It doesn't need scaffoldings so it is efficient and economic. Concrete-wall climbing machines generally use suction cups to hold their body. However, climbing testing machines have dangerousness of falling down. The causes of the falling down are inadequate decompression of the suction cups and slip between the suction cups and concrete wall. The inadequate decompression can be avoided by moving the suction cup. We had developed suction cups preventing slip on concrete wall by using claws. Claws are equipped on the suction cups and get the wall tightly. In this paper, scratch test of a claw on concrete plates, concrete blocks and red bricks have been done to get the maximum holding force of the suction cups. According to the results, the method to determine dimensions and pressure of suctions was discussed.

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This study proposes a moving mechanism using an Archimedes' screw for propelling a snow surface layer. In order to predict the occurrence of surface avalanche, a movable capability without breaking a layer of fresh snow on the surface is required for an avalanche search robot. Because it is too heavy, the moving mechanism using a crawler that has been used conventionally can't move on a layer of fresh snow. However, this problem is solved by employing the Archimedes' screw because it is a lightweight device. Movement ability of the proposed system is largely dependent on the mechanical properties of the snow surface layer. Particularly, the subduction depth of snow layer which is compressed and the maximum shear load which doesn't break a layer of fresh snow are important properties. In this paper, the mechanical properties of the measured snow surface layer are reported. Further, moving ability of the proposed system is evaluated on the basis of the measurement results.

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The sliding down of a heavy work machine causes serious accidents in the construction industry. The factor of sliding down is the slip of it. Conventional studies of preventing the slip have been studied for four-wheeled vehicles with the driven tires. However, these conventional methods often used rotational speed of the driven tires. Generally, an electric crawler vehicle does not have the driven tires. Therefore, we propose the slipping suppression control without the rotational speed of the driven tires. The proposed method uses only an electric current of drive motors for judgement of the slipping. We have tested in order to confirm the effectiveness of the proposed method in low μ, road. Finally, we show the effectiveness of the proposed method from experimental results.

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Many locomotive robots have been created for inspecting the social infrastructures such as a lot of bridges and tunnels that had been constructed in many years. Installation of a small camera and a wireless LAN module to the locomotive robot is necessary to control it remotely. The camera image must be encoded to transmit the data from the robot in advance because the throughput of wireless LAN is limited. The compressibility of the image compression through discrete wavelet transform and arithmetic encoding is very high. However, the calculation load is also large. A highly efficient personal computer cannot be installed in the robot when the robot is small. FPGA becomes the most powerful candidate as a main controller for the small robot. However, it is not good at arithmetic operation because FPGA is an electric circuit. Especially, use of floating-point numbers, the multiplication and division calculations are difficult for the FPGA. In this study, the multiplication and division calculations have been excluded from the discrete wavelet transform and arithmetic encoding so as to make program easy in FPGA. Then, I have prevented the emergence of floating-point numbers in the calculation. I have created the VHDL program and the sending and receiving device of the encoding and decoding. The image data captured by a CMOS camera have been projected onto the display monitor on the receiving side.

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We have developed a high-speed movement and omni-direction movable wheel module (WM11-01). And we proposed the wheeled Multi-purpose Module System (MMS-V01) which is consist of series of two WM11-01. The body configuration of MMS-V01 are arranged four mecanum wheel on one axis, each of mecanum wheel is driven independently. MMS-V01 is capable of omni-directional movement at high-speed and have an elongated body to move in a narrow space such as a pipe. An omni-directional and a pivoting movement of the MMS-V01 is analyzed by simulation to evaluate the performance of the MMS-V01. The relationship between the rotational speed of the wheel and the movement trajectory of MMS-V01 is observed. The result indicated that the MMS-V01 is capable of omni-directional movement and pivot movement at high speed by giving the rotation speed and direction of rotation of the wheel.

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In this paper the technique which improves exercise capability of 4-wheeled robot equipped with a tail is discussed, and a design method of input for long jump of the robot is proposed. This method is useful when the robot cannot advance for a crack in the ground.

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