This paper deals with cutting phenomena in micro end milling. Cutting experiment was conducted by small milling machine and micro end mill was used. Cutting torque was monitored during milling under various cutting conditions. Tool wear and surface roughness were measured in interval of constant cutting length and cutting force components were measured by dynamomete at that time. As the results, spindle speed at which tool wear was minimized existed in this experiment and feed rate hardly affected on tool wear. Surface roughness at bottom was deteriorated by interference between tip of tool edge and bottom of work, caused by deflection of tool.

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In external turning of carbon steel without/with ultrasonic vibration (abbreviated to USV), the effect of crystal structure, hardness, surface roughness, residual stress and surface energy on corrosion is discussed. Corrosion of the machined surface is investigated for humid environment and salt water. As a result, in cutting without USV larger corrosion occurs, and built-up edge (abbreviated to BUE) generation and large surface roughness cause the corrosion. The position of BUE fragments corresponds to the origin of corrosion. And also, the residual tensile stress on the machined surface in cutting without USV can easily occur the crack on the machined surface, which can, in turn, increase the generation of corrosion.

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In general, the three-dimensional free curved dies of iron based alloy have been engraved with the coated carbide tool or the CBN tool. In this case, it is difficult to get high accuracy surface, without abrasion process after engraving process. Because diamond is the hardest material in naturally occurring minerals, single crystal diamond tools have sharp edge that tool commonly used for ultra precision cutting. However, it has long been known that tool wear is excessive when diamond tools are used to cut steel or iron based alloy. In this paper, end milling, which is an intermittent cutting operation, was utilized to suppress wear on the single crystal diamond tool for cutting steel. End milling is commonly used to produce free curved surface parts. The work material was stainless steel (SUS420J2) 2mm×5mm in size. In the basic experiment, it was found that the utilization of mist is affective to reduce tool wear, but is no effective to improve surface roughness. Surface roughness was improved by the tool geometry, and clearance angle and swing radius have to be determined properly to consider cutting conditions. The selected experimental conditions of clearance angle of 20° and swing radius of 2mm, the fine machining surface can be obtained, and the surface roughness was around 100nm Rz.

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In the metal cutting, a mechanical energy is transformed into the heat. The heat flows into workpiece, chip and tool. It will cause the thermal expansion. After the machining, the workpiece temperature decreases to normal temperature and then the residual stress is induced within the machined layer. The residual stress causes distortion of the machined components. In addition the tensile residual stress degrades the fatigue strength. Thus, it is important to quantitatively elucidate the correlation between the residual stress field and the machining errors. In this paper, a thermal-elastic-plastic model was developed to determine the thermal energy flowing into workpiece, chip and tool. The residual stress distributions in the workpiece during a sequential cutting process are predicted by FEM analysis. Especially, the effect of the time interval between two successive cuttings and the effect of cutting conditions on the residual stress field of the workpiece was investigated.

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There are strong demands for a machining process capable of reducing the suface roughness of sliding parts, such as auto parts and other components, with high efficiency. In this work, we attempted to grind hardened steel to a mirror-like surface finish with high efficiency using an ultrahigh speed grinding process with a coarse-grained cBN wheel. In the present study, we examined the effects of the rotary diamond dresser grain size, the dressing conditions and the work speed in an effort to optimize the grinding conditions for accomplishing mirror-like surface grinding with high efficiency. The results showed that the thickness of work affected layer reduces when the work speed was increased while the grinding efficiency was kept constant. Furthermore, under a finer dressing condition, increasing the work speed was effective upon reducing the deterioration of surface roughness due to grinding heat. However, grinding chatter is likely to occur with higher work speed.

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The present authors previously proposed a new centerless grinding method using surface grinder. In this method, a compact centerless grinding unit composed mainly of an ultrasonic elliptic-vibration shoe is installed onto the worktable of a multipurpose surface grinder to perform tangential-feed centerless grinding. Its validation was also confirmed experimentally. In order to further enhance the performance of the new method, it is crucial to understand the workpiece rounding process, and the effects of the process parameters such as the worktable feed rate, the grinding allowance, and the workpiece rotational speed on the machining accuracy, i.e., workpiece roundness should be clarified. In this paper, at first a grinding model is considered and the basic equations for the simulation analysis of workpiece rounding process are created. Then, simulation analysis is carried out to predict the variation of workpiece roundness during grinding and to discover how the process parameters affect the roundness. Finally, actual grinding operations are performed by installing the previously constructed unit onto a CNC surface grinder for the confirmation of the simulation results. Both the results indicated that (1) Smaller worktable feed rate and higher workpiece rotational speed give the better roundness; (2) The better roundness can be obtained when the grinding allowance is set up at a larger value.

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Smooth and flat surface of glass plates should be needed for the HDD substrate. Polishing with free abrasives made smooth surface, however it is difficult to obtain flat surface because of the nonuniform distribution of free abrasives. In order to overcome such issue, we tried to apply magnetic force with magnetic fluid and magnetic field for uniform distribution of abrasives during polishing process. By applying 20mT of normal magnetic filed to the copper polishing plate with magnetic fluid as polishing liquid, surface roughness of polished glass plate improved by 20-60%. And flatness of polished glass decreased to half with magnetic fluid and magnetic filed.

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The specific gravity of cerium oxide used for glass polishing as abrasives is very heavy so that the cleanability of workpieces and the dispersibility in polishing slurry are very bad. Then composite abrasives that put the abrasive grains on the surface of the polymer particles with light specific gravity were developed in this paper. For manufacturing the composite abrasives, it was found that the hybrid mixer with two axis rotation method was more suitable than hybridization system with one axis rotation method. The residual abrasives were still observed though cleanability was considerably improved by using the composite abrasives. Because it was made clear that the loose abrasives were deteriorated of the cleanability, classification using the subsidence speed difference was carried out. As the result cleanability and surface finish were improved very much using the classified composite abrasives. Next the material of the mother particle was examined. The polyurethane was suitable for glass polishing, and higher removal rate was obtained than that of conventional polishing.

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A direct metal rapid fabrication process using an arc welding is developed. This methodology is based on the layer manufacturing process of the molten metals supplied by the arc discharge. In this report, it is shown that the overhanging shape consisted of the inclined wall can be fabricated by the proposed process. Then some causes which degrade the shape accuracy of the fabricated inclined wall are investigated. Firstly, the inclination angle becomes larger than the intended angle because the molten metel distributes downward because of the gravity and the arc force. Secondly, at the initial stage of the accumulation, the wall inclination angle tends to be small because the arc point location shifts upward on the previously formed bead. Thirdly, the heat capacity and temperature around the accumulating point largely affect the accuracy of the inclination angle.

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The study deals with the development of a new CAD/CAM system for fabricating the holes whose cross sections are changing variously. The realizable hole shapes by machining are generally limited. As a typical example, a cross section of a machined hole is constant. To solve the problem, a new device had developed which could create cross section's changing holes by means of electrical discharge machining. However, it was impossible to put the device into practical use, since the software system for the device did not exist which allowed the device to machine an arbitrary cross section's changing hole. Accordingly, the study aims at the development of a new CAD/CAM system to realize such a machining. As the first step, in this paper, the post processor of the CAD/CAM system is formulated to machine 2-dimensional cross section's changing holes. The post pocessor outputs operating program of the device by inputting movement path of the electrode. The results obtained from the experiments show that the post processor can machine 2-dimensional, complicated cross section's changing holes by inputting electrode location data.

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In this paper, a feeder setup planning problem of a gantry-type placement machine is investigated to increase productivity of printed circuit board (PCB) assembly line. We propose a new planning algorithm based on offline setup strategy that exploits a cart swapping mechanism of the gantry-type placement machine. Because of computational complexity, we adopt a hierarchical decomposition of the planning problem. Important subproblems are PCB sequencing and feeder assignment. We solve heuristically the PCB sequencing problem using 2 way balanced partitioning of a hypergraph. For the feeder assignment problem, we develop a mixed integer programming model and solve it using branch-and-bound method. The proposed algorithm is tested on real-life PCB data. It is shown that the productivity of offline setup strategy is better than that of group setup strategy and our algorithm achieves significant improvement in productivity.

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In order to measure the 3D shape of microcomponents, a novel nano-CMM system has been developed based on an oscillated probing technique, which uses an optically trapped particle. The trapped particle is laterally oscillated at the focal plane of the objective. The frequency response of the oscillated particle typically agrees with the spring-mass-damper model. However the response disagrees with the theoretical curve of the conventional model equation in the range of high frequency. It is considered the difference between experiments and the model equation is caused from the numerical error for the fluid effect, which is applied on condition of creeping flow past a sphere. In this report, we construct a fluid simulation using SMAC method that calculates fluid resistance against an oscillating sphere in noninertial frame of reference. The fluid resistance damp the motion of an oscillating sphere pulled toward focal spot and spring-mass-damper system can be processed with the use of simulation.

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Because of retirement of many middle-aged technicians, passing on skills of middle-aged technicians to the younger generation becomes the recent interest in Japanese industry. In order to support of passing skills on cutting technology, support tool which can reveal techniques and knowledge of the skilled engineers is developed. The tool enables the collection, classification, and storing of applicable skills.

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Rolling stock has been generally inspected and maintained on the basis of the preventive maintenance. However, the reliability of the sensors and information technology has drastically improved, and with this background the objective of this research is to develop the condition monitoring system for the bogies of the Shinkansen cars. This paper describes an algorithm for detecting fault in some parts of bogies. This scheme is based on the statistic analysis of vibration acceleration during some period. This algorithm named peak average method detects the difference of the vibration peak distribution between fault cases and normal ones. For examining the possibility to detect fault in the bogie, experiments simulating some fault modes in bogie parts are conducted in the rolling stock test plant at Komaki Research Center of CJRC. From the results of these experiments, we can show the reliability and the validation of this scheme for monitoring conditions of Shinkansen bogies developed in this research.

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Transport and mitigation technology of lunar dust has been developed utilizing the electrostatic traveling wave applied to the electrostatic conveyer consisting of parallel electrodes. Four-phase rectangular voltage was applied to electrodes because it was most efficient compared to the sine or triangular wave. Traveling-wave propagation was achieved utilizing a set of positive and negative amplifiers controlled by a microcomputer. The power system was designed simple, small, and lightweight for the space application. The transport rate of more than 90% was realized in vacuum with this system under conditions of 700V voltage and less than 100Hz frequency. However, very small particles adhered mainly on the electrodes, probably due to the electrostatic image force, and they were not transported. The adhered dust was increased but saturated to the repeated operation. Because it is assumed that the lunar dust is charged by the irradiation of the solar wind and the cosmic ray, it was investigated whether initially charged particles can be transported efficiently with this system. The transport rates with positively charged particles (+0.6μC/g) and negatively charged particles (-0.6μC/g) were almost the same to the rate without charge. The power consumption of this system was measured and it was estimated that it takes only 0.08Wh for once operation of a 1m^2 conveyer. Numerical investigation was carried out with a three-dimensional hard-sphere model of the Distinct Element. Method to clarify the mechanism of the transport. This technology is expected to be utilized for the transport and mitigation of lunar dust for the lunar exploration.

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One of the major problems in machining plane cam with complex curvatures is the machining accuracy of the cam surface. This is due to the deviation of tool tip from theoretical tool trajectory which caused by changing the radial chip thickness. As a solution, in this paper, a new method is proposed to improve the machining accuracy of plane cam. In this method the cutting feed rate which is calculated by considering the radial chip thickness is controlled. This method was applied to two types of cam profiles. The measurements were carried out by using three-axis coordinate measuring machine. The results show that the controlling cutting feed rate improves the machining accuracy of the plane cam than constant feed rate. This is verified by measuring the spindle load. Further more the controlling of cutting feed rate in this method is not affecting on the machining time. Therefore the proposed method is suitable for machining plane cam with complex curvatures.

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When an elevator rope for a high-rise building is forcibly excited by long-period ground motion, rope displacement becomes large even if the ground acceleration is small. Therefore, detecting the rope sway in real time is important to avoid damage during and after earthquakes. In a previous method for calculating the rope vibration using the finite difference method (FDM), excitation waves are the machine room displacement and the ground displacement. However, these displacements cannot be directly obtained because acceleration is measured by seismic sensors. In this paper, a simplified calculation method, based on a single degree of freedom (SDOF) system, for estimating rope displacement during an earthquake by using the building's acceleration and ground acceleration is presented. Finite difference analyses of rope vibration are also performed to verify the validity of the simplified method. The results of this simplified calculation method agree with those of the conventional finite difference method, within the 20% error margin.

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This paper presents a novel smart film sensor developed in the work using an electrode patterning technology. Conventional smart sensors based upon a PVDF film are first shaped in accordance with a desired shaping function, and then attached onto a substrate, thereby causing less-accuracy and less-traceability of a dynamical behavior especially at high frequencies. To overcome such problems, this paper introduces a photo-resist technique on electrode patterning of a PVDF film, with the result that the PVDF film becomes a distributed parameter smart sensor per se, hence shaping and attachment handling are no longer needed. Firstly, this paper overviews a two-dimensional modal filtering sensor for extracting several structural modes. Then, a systematic design procedure of a high-definition electrode patterning on a PVDF film is proposed. Furthermore, a PVDF film-based cantilever beam entailing the capability of modal filtering is developed, the validity of the proposed smart film sensor being analytically as well as experimentally verified.

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The frictional behaviour is effective for dissipating seismic energy. Therefore, in recent years, the installation of a frictional isolator in industrial facilities has been investigated. However, the seismic response of the friction system is obtained only by non-linear time history analysis. A great deal of time is required for non-linear analysis. The present study deals with the easy estimation of seismic response for a multi-dof system with friction. In the previous study, the authors suggested the easy estimation of the seismic response of a 1-dof friction system using a friction response spectrum. In addition, the modal analysis method for a 2-dof friction system when the mass ratio of the structure by support is nearly zero was proposed. First, the present paper proposed the estimation method of a seismic response for a 2-dof friction system based on a friction response spectrum and modal analysis method. Secondly, the applicable range of the proposed method is suggested by comparison with the result of non-linear time history analysis. The proposed method can obtain the seismic response of a 2-dof friction system immediately without non-linear time history analysis.

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Homopolar flywheel is considered to be very efficient and a good candidate for next-generation energy storage device, compared to the conventional (heteropolar) flywheels. By the help of active magnetic bearings, in this paper we are proposing a method to control the attitude of this low-loss flywheel. Many studies had been established in the past using gain-scheduling control and other methods but these need additional information (i.e., flywheel rotation speed) as an input. Without this information, it was difficult to control the flywheel. Here we introduce a new and more robust method using Multi-Input Multi-Output Simple Adaptive Control (MIMO-SAC) with an improved adaptive identification.

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In this paper, variation of airborne sound absorption coefficient for granular material with small quantity water is dealt. The granular matter under the test is solid glass spherical grain as diameter 1mm. The relationship between water content by volume and absorption coefficient for each thickness of layer is measured by experiments. And tortuosity as one of the Biot's parameters is also measured by ultrasonic. It was proved that peak frequency of absorption coefficient decreases as increasing of water content. The reason is that reduced virtual sound velocity makes effect of larger sample thickness. Result of this study is useful for expecting absorption coefficient of wet or liquid bonded granular matter.

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An air conditioning equipment is usually set to keep a rail vehicle comfortable. However its noise is annoying especially when the vehicle is stationary. The noise reduction is very important from the point of view of keeping the car interior space comfortable and is one of the differentiating techniques for the manufactures. This paper describes characteristics of flow noise generated from the duct with some holes. Both the acoustic experiment and the flow experiment were carried out in various parameters such as the flow velocity, the absorbing ability and the hole area by use of the straight duct. As a result, it was clarified that the noise reduction effect of the absorbing treatment could be neglected when the noise source was made only by the flow and is much when the fan noise is greater than the flow noise. Moreover the effect of the flow on the noise reduction effect of the absorbing treatment could not observe in case of the velocity being less than 30m/s.

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In this study, in order to improve effectiveness of the abnormal signal detection, we first developed a novel parasitic discrete wavelet transform (P-DWT) to perform fast wavelet instantaneous correlation (F-WIC) and then proposed a new design method of the parasitic filters for the P-DWT. Furthermore, we showed a judgment standard for assessing the credibility of the abnormal signal detection by using the P-DWT. Finally, we applied the F-WIC to car rattle noise source identification and showed that our method can improve computation efficiency and obtain sufficient calculation accuracy at the same time.

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This article proposes a new control method that is able to achieve the precise posture control of an object grasped by a two soft-fingered robot hand. This method consists of two parts: an integral controller of the object orientation and a PD controller of joint angles. The former contains desired joint angles of both fingers, which is obtained by accumulating the deviation of the object orientation by the integral control. The latter produces a constant torque term to accomplish the stable grasping of the hand, and generates requisite torques for precise manipulating of the object. As a result, this controller does not need force informations induced on the soft fingers. We verify the performance of the present new control method by simulating a given motion, and demonstrate it by implementing the handling experiments by means of a minimal degrees-of-freedom robotic hand. Finally, we make a discussion in terms of the effectiveness of the control law and stable grasping and manipulation on soft-fingered hands.

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PID controlers are generally used to control mechanical systems. PID controlers, however, have a limit of robustness because of the influence of gravity, friction, and interaction of joints which cause modeling errors. A digital acceleration control has robustness for the modeling error. Therefore, the digital acceleration control is more effective than PID control. But it requires position, velocity, and acceleration of a controlled object to construct the controller. Information of velocity and acceleration cannot be always obtained in mechanical systems. Furthermore, it is desirable that the number of sensors is reduced for the purpose of cost and maintenance. To solve this problem, the system that Estimates the Smoothed and Differential value by using Sliding mode (ESDS) is employed. The ESDS enables digital acceleration control without increasing the number of sensors. This paper shows the results of the proposed control method by using a horizontal planar 2-link manipulator.

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Postural steadiness (sway) is used to evaluate the dynamics of the postural control system associated with maintenance of balance during standing. Recently, the chaotic behavior of many biomechanical systems has been examined using Lyapunov exponents, fractal dimension or attractor plot (reconstructed phase portrait). The purpose of this study was to investigate the effects of physical workload on postural stability during load holding task by measuring sway of center of pressure (COP). The experimental variables were weight of load (10kg, 15kg, and 20kg) and height of holding a load (50cm, 70cm, and 90cm). Ten male subjects participated in a repeated measures experiment in which 9 lifts were performed. The time of holding a load was for 10sec. The sampling interval was 1msec. The basic measures of postural stability (mean distance of the COP, mean velocity of the COP, and sway area) and the chaotic measures (fractal dimension and first Lyapunov exponent) of the COP were calculated. When the holding height increased, the mean velocity of the COP tended to increase but the first Lyapunov exponent of the COP decreased. On the other hand, the fractal dimension of the COP decreased with the increase in load weight. From the above results, it was clarified that physical workloads (load weight and holding height) affect the chaotic measures of the COP. It was implied that the physical workload can be measured by the chaotic features of the COP.

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This paper describes the effect of traction oil on the power loss of a spur gear drive. In this study, we measured the power loss of the spur gear drive using several traction oils. We separated the power loss into gear friction loss and oil churning loss. Furthermore, we measured the surface temperature on the gear tooth by the dynamic thermocouple method, and observed the lubrication condition between meshing teeth by the electrical resistance method. Then, we investigated the relationships among the power loss of the gear drive lubricated with the traction oil, the gear tooth surface temperature, and the lubrication condition.

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In case of usual gearing, it is possible to know the meshing condition of the gear by measuring the strain on the root of the tooth. However, it is impossible to stick a strain gauge on the root of the tooth, because the module is too small in case of the strain wave gearing. Therefore, in this study, the space was cut off at the rim part of the circular spline, which was one of the components of the strain wave gearing, by the electric discharge machine, and the strain gauge was stuck there. The consideration on the simultaneous meshing number of teeth was carried out with the measured value of the strain on the root of the tooth got by load tests using this special strain wave gearing. The results showed that 18% of all teeth meshed simultaneously in case of the no-load torque and that 34% of all teeth meshed simultaneously in case of the rated load torque.

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Specifying the origins of ghost noises produced at non-integral multiples of gear meshing orders from the order at which they occur represents a challenge, and determining countermeasures for these noises has involved a process of trial and error. Today, with the widespread use of a method of continuous generation involving the use of a multiple-thread-type tool for high production efficiency in the process of grinding the flanks of the helical gears used in automotive transmissios, new ghost noises have appeared. The research discussed in this paper clarified the mechanism behind the production of the ghot noises that have become noticeable as a result of the use of the multiple-thread-type tool, and identified the relationship between the orders at which the noises occur, the level of undulation on lead form that cause ghost noise and the conditions used in the grinding process. Then the project verified these findings in an actual transmission.

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This study aims to develop and propose an oscillation contolled lapping method, which uses a small diameter lap tool and is classed in the single wafer lapping system, as an effective method to achieve high precision controlled lapping of large sized silicon wafer. Our previously paper shows the fundamental controlled lapping characteristics under both the theoretical and the experimental examinations. On the other hand, the lapping characteristics are affected by the slurry flow. And also, the lapping chracteristics by the proposed method are changed with tool overhanging. Therefore, this paper describes the relations among the slurry flow, pressure distribution with tool overhanging and lapping characteristics of the proposed method based on a series of experiments and theoretical results using finite element analysis. It is founded that the slurry flow mechanism is changed greatly with an offset between the tool and the workpiece. Moreover, the controlled lapping within under 1μm is achieved by the proposed method.

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Multi-tasking machine tools are powerful to manufacture complicated workpieces with high productivity. However, NC data generation for multi-tasking machine tools is very difficult in general when using such machine tools. There are some CAM systems for multi-tasking machine tools, however they have such problems as the manual allocation of parts to generate tool paths, the difficulty of self-interference recognition without simulator and so on. Therefore, this study deals with the development of the system which can recognize part configurations, calculate tool paths automatically for turning and milling operations and sort them in machining order, based on 3-D CAD data of workpieces and target shape.

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This study is concerning the optimum design of a water nozzle for firefighting equipment used to protect large indoor spaces and high-rise buildings. Water nozzles for such use are required to have a long range of reach and/or a wide coverage. Such performance can be obtained by simply increasing the flow rate, but that is caused substantial pressure loss by the fluid friction within the nozzle and the pipe. The objective of this study is to obtain a water nozzle with minimum fluid friction by optimum design, as a result the size of piping, pump and water reservoir for firefighting equipment can be minimized. The conventional water nozzle used in firefighting is called the smooth bore nozzle, which have a wedge-shape profile whose diameter decreasing toward the exit. However, whether or not this shape is optimum have not been known. In this study, a method is presented to obtain a friction-minimum nozzle profile, while setting the inlet-and outlet-diameters and the length of the nozzle as fixed parameters. It was found that the half-spindle-type nozzle, whose diameter is almost constant along the length but quickly decreases at the exit, shows the smallest friction than the other profiles (i.e. smooth-bore, straight and concaved), therefore showing maximum arrival distance.

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