This paper deals with a forced vibration of strongly coupled subsystems. A theoretical and practical approach is proposed to obtain targets of the subsystem's vibration properties which fulfill the target of whole system. The approach is an application of transfer function synthesis method and provides a procedure to analyze the compliance of subsystems at connecting points for setting the natural frequency and reducing the internal forces. A new concept of kernel dynamic stiffness and kernel vector is introduced to understand vibration transmission in the analysis of the compliance at connecting points. This approach is applied to vehicle noise issue induced by road roughness (road noise) in the frequency range of 80 Hz and 150 Hz on macpherson strut type suspension. The results show effectiveness of this approach and present guideline of the suspension design for road noise.

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The generalized transfer stiffness coefficient method using the graph theory is developed in order to improve the applicability of the transfer stiffness coefficient method. In the new method, an analytical model is expresed by a signal-flow graph, and the graph is contracted according to the series and parallel contraction rules. The computational complexity and the memory requirement for the contraction process are both minimized by choosing the optimal contraction route. In addition, it is possible to develop the data-driving program which is applicable to various structures without updating the source program. An algorithm based on the present method is formulated for free and forced vibration analyses of a two-dimensional framework structure. Furthermore, a treatment for applying to a three-dimensional framework structure is described in brief. The validity of the present algorithm is confirmed by the numerical computational results.

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A moving apparatus utilizing a self-synchronized phenomenon is developed. This system consists of two mass-blocks coupled by a spring and a dashpot, and a pair of two unbalance masses rotated by DC motor is mounted on each mass-block. When a comparatively close voltage is supplied to each DC motor, the unbalance masses on the mass-blocks rotate at the same average rotational speed automatically and also the mass-blocks vibrate in the coupling direction at the same frequency. The system, then, moves on a floor at a constant average speed due to an unsymmetrical property of dry friction force acting on each mass-block from the floor. The automatically synchronized rotation of the unbalance masses can be regarded as a self-synchronized phenomenon. In this report, the basic property of the moving performance is analyzed by applying the improved shooting method and the analytical results are verified by comparing with experimental ones.

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In this paper, we propose the exact derivation method of all periodic solutions for zero stiffness forced vibro-impact systems with viscous damping. First, specific initial condition which correct and periodize general solution is determined using pseudo-feedback approach. By means of substitute this initial value into globalized general solution, global form of all periodic solutions which includes symmetric and asymmetric type can be represented by superposion of periodic stationary solution of linear system and finite number of weighted summation of periodic functions caused by impact nonlinearity and their constants parts. Two types of invariant relations for quantity of periodic solution also derived. Finally, numerical simulation calculating typical asymmetric periodic solution is perfomed, the validity of proposed method is confirmed.

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This paper deals with impact vibration in continuous system excited by periodic displacement with arbitrary functions. The analytical model is a system of steady collision vibration with an attached mass in simply supported-beam at both ends. The attached mass collides elastically with clamped spring of asymmetrical faces. In order to clarify the main resonance of the system subjected to excitation by displacement, the resulting vibrations are analyzed using the Fourier series method and an exact solution is proposed for this system. Following the theoretical analyses, numerical calculations are performed, and the resonance curves are made using the resulting vibrations. Effects of the stiffness of clamped spring, the ratio of attached mass and the amplitude of excitation on the resonance curves are shown by numerical results. For verification of the analytical method, experiments are also performed. The numerical results are in a fairly good agreement with the experimental ones.

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Tainter gates used for regulating the back water level of dam may be designed so that the skinplate center is kept under the trunnion pin. Such gates may be called an “eccentric Tainter-gate”, which is statically stably but dynamically unstable. This study presents a design criterion for dynamic stability of eccentric Tainter gates, which is theoretically derived in a practical form, that is, in a non-dimensional expression of the Scruton number representing the mass-damping parameter vs. the Froude number representing the dynamic similarity of fluctuating flow in the back water. In addition, in-air and in-water free vibration tests are made for two of Tainter-gate models with different size and eccentricity, and the measured data of Scruton number is plotted over the tested Froude number, and the design criterion for dynamic stability of the eccentric Tainter gates is verified for its practical validity.

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This paper describes the driving at a resonance point of an elliptical vibratory machine that consists of a horizontal vibratory system and a vertical vibratory system. The driving of the vibratory machine by self-excited vibration, which is generated by positive feedback of velocity, follows the change of resonance frequency automatically and reduces electric power consumption. The resonance of frequency of the horizontal system and that of the vertical system cannot be completely made in agreement, so then self-excited vibrations in both systems differ in frequency. The synchronization control using frequency entrainment drives both systems at the same frequency in the middle of the two resonance frequencies, and both systems can vibrate in a state of near resonance frequency. Furthermore, phase shift filters in the synchronization controller give a desired phase difference between horizontal vibration and vertical vibration. By combining self-excited vibration driving and the synchronization control, an elliptical vibration locus can be kept constant and an elliptical vibratory machine can be driven efficiently.

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For Above Deck Equipment (ADE) on a ship, it is necessary to perform experimental modal analysis (EMA) by base excitation. Existing EMA tools are designed to perform curve-fitting on the frequency response function of displacement or acceleration at measuring point to an excitation force. However, in case of experiment by base excitation, transmissibility of acceleration, that is, the ratio of accelerations between measuring point and base is to be used for modal analysis. A method, which makes modal analysis for base excitation possible by performing curve-fitting on the transmissibility of acceleration using existing EMA tools, is proposed in this paper. First, the relation of transmissibility of acceleration using modal parameters in case of base excitation is derived. Based on the relation, a new method for modal analysis is given and its feasibility for one D. O. F. system is shown by numerical calculation. Finally, the method is applied to the modal analysis of an ADE, and its effectiveness is shown by comparing experimental results with simulation results using the modal parameters obtained by the method.

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We applied an improved capacity spectrum method (ICSM) to a piping system with an asymmetric load-deformation relationship in a piping elbow. The capacity spectrum method can predict an inelastic response by balancing the structural capacity obtained from the load-deformation relationship with the seismic demand defined by an acceleration-displacement response spectrum. The ICSM employs (1) effective damping ratio and period that are based on a statistical methodology, and (2) practical procedures necessary to obtain a balance between the structural capacity and the seismic demand. The effective damping ratio and period are defined so as to maximize the probability that predicted response errors lie inside the -10 to 20% range. However, without taking asymmetry into consideration the displacement calculated by using the load-deformation relation-ship on the stiffer side was 39% larger than that of a time history analysis by a direct integral method. On the other hand, when asymmetry was taken into account, the calculated displacement was only 14% larger than that of a time history analysis. Thus, we verified that the ICSM could predict the inelastic response with errors lying within the -10 to 20% range, by taking into account the asymmetric load-deformation relationship of the piping system.

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This paper presents a method of estimating a constrained mode model of a spacecraft using on-orbit flight data. A constrained mode model is widely used for modelling dynamics of flexible satellites and convenient to compare a flight model with a ground model. The developed method, which is based on a similarity transformation of a state-space model, yields a constrained mode model from a system identified in an arbitrary form. The method was applied in a case study to the on-orbit system identification for the Engineering Test Satellite-VI (ETS-VI) using simulated responses to thruster impulses.

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It is well known that asymmetric vane spacing can result in decreased levels of the excitation at specific frequencies. In this paper, the resonant response reduction of compressor blades due to asymmetric vane spacing is studied both theoretically and experimentally for the most probable asymmetric vane in which the vane count of the upper and lower half is slightly different. First, a method for predicting the vibratory stress of the blade for the asymmetric vane spacing is proposed. Secondly, using a simple model of the asymmetric vane, a parametric study is carried out to clarify the influence of blade damping and vane count on the blade resonant response reduction. Finally, experiments are carried out to verify the validity of the proposed method and the effect of asymmetric vane spacing on resonant stress response using a 3 stage scaled-model compressor.

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We developed a diagnosis method for an abnormal rotor vibration with reducing lubricant in tilting pad journal bearings. We suggest a method of diagnosis based on a statistical approach using repetition in an incidental vibration signal. That repetition is calculated using normalized amplitude of vibration for each frequency to diagnose anomalies early. The time-frequency characteristics of vibration amplitude were calculated using continuous wavelet analysis. On this diagnosis method, we compared measured repetitions with pre-measured repetitions of abnormal vibrations using inner products. We applied the diagnosis method to the measured vibration. We found that incidental low-frequency vibration occurred by reducing the lubricant, and the low-frequency vibration became a steady high-frequency vibration as the lubricant decreased. The diagnosis method detected the occurrence and the transition of the rotor vibration when lubricant in the bearings was reduced.

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In the seismic design of nuclear power plant, it is recently considered to apply the probabilistic method in addition to the deterministic method. The deterministic method secures the seismic safety of a nuclear power plant by veryfying that the calculated stress on the equipment is lower than allowable stress in the design criteria. The seismic probability safety assessment (Seismic PSA) method secures seismic safety by veryfying that the probability of reactor core failure is lower than a certain value. In seismic PSA, it is important to estimate the fragility of the equipment for precise assessment. Therefore, in this paper we dealt with a method using the Bayesian approach to generate a fragility curve of power plant from a multi-specimen test, and investigated the influence of the sample size driving the fragility evaluation test

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To improve the vibration control performance of dynamic vibration absorber (DVA), various multi dynamic vibration absorbers have been introduced for several years. Although the multi DVAs are better than single-mass DVA in vibration control performance with the same mass ratio, their vibration control effects are also very sensitive to the change of natural frequency of the controlled object same with single-mass DVA. In this paper, a new robust optimal design method has been proposed for improving the robustness of multi DVAs in vibration control performance. Optimal parameters of the two-series-mass DVA, two-parallel-mass DVA and four-parallel-mass DVA have been calculated and optimal design diagrams and approximate formulas are conducted. Robustness of vibration control performance is analyzed with the simulation and experiment. The results show the robust design method is better than conventional compliance optimal design method in robustness of vibration control performance.

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This paper deals with a large flywheel magnetic bearing system. A simple rigid model was derived based on overlapping principle. A servo system backstepping controller taking into consideration of the gyroscopic effect was designed. The switching method for the control current was chosen to avoid the use of bias current. Through simulation and experiments, the effectiveness of rigid model and stability of the controller was verified. Meanwhile, the power consumption using the proposed controller is reduced by half compared to bias current control. Faced with the problem that the rotor cannot overcome a high critical rotational speed, a flexible model based on finite-element method was derived and used in place of the rigid model, applying the same controller. From the result of root locus analysis of closed-loop system, a conclusion can be drawn that it is important to the magnetic bearing system to design a controller considering the gyroscopic effect based on a flexible model which includes two rigid modes and a first flexible back mode.

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In the argon distillation columun, the argon-yield rate increases to some values in proportion to the nitrogen concentration in its source gas from the oxygen columun, but it decreases after the nitrogen concentration exceeds a certain value. Therefore, for the improvement of the argon-yield rate, it is important to stabilize the nitrogen concentration to the desired value. For realizing this control, an indirect continuous measurement method of the nitrogen concentration, mathematical auto-regressive models with dead time of the process and an optimal control system of the plant have been developed, and the improvement of about 3% has been confirmed by their practical applications to a high pressure type of plant.

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The work presents the wheeled walking frames that are supporting equipments, to be used by elderly people or handicapped in rehabilitation. Mostly, standard frames have weakness in walking on upward/downward slope. People often need power assistance on upward, and need secure walking support without falling on downward. The purpose of this paper is to develop a speed control assisting unit for wheeled walking frames by using the generalized internal model control (GIMC) with LQ control. By selecting appropriate parameter, the control method has various type of control scheme. Effectiveness of the assisting unit is confirmed by comparative experiments on upward and downward slopes. The result shows that the proposed method is effective on speed control for the assisting unit of wheeled walking frames.

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This paper deals with the acoustic resonance in tube bundles which occurred in actual boiler plants. In-situ measurements revealed that besides the lift-force directional modes, drag-force directional modes which are difficult to suppress, are generated. In order to suppress both types of resonant modes, acoustic absorbers are adopted which are equipped mid-air in the duct. This phenomena is classified as self-exited oscillation and based on the stability criterion, its design method, including the number or placement of absorbers in the duct space for efficient performance, was developed with the use of acoustic FEM. In order to validate this method, scale model test was executed and the same phenomena as those in the actual plant were realized. In the next step acoustic energy absorbers are equipped in the duct and remarkable increase of the critical flow velocity was confirmed. Finally this method was applied to the actual boiler plant and based these results, it was confirmed that the proposed method is the effective countermeasure for the anti-acoustic resonance in heat exchangers.

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A basic research has been being carried out on transport of a liquid drop in electrostatic traveling field. A liquid drop conveyer consisting of parallel electrodes was constructed and four-phase traveling electrostatic wave was applied to the electrodes to transport the liquid drop on the conveyer. The following were clarified by the experiment : (1) Electrostatic transport of the liquid drop was demonstrated in insulative insoluble liquid. (2) The drop was charged on the conveyer by the friction and driven by the Coulomb force. The polarization force was also applied to the ralatively large drop. (3) The liquid drop that covered less than three arrays of the electrode could be transported in the traveling wave field. (4) The mode of liquid transport was classified into two; synchronous region that liquid drop motion was synchronized with the weve and delayed region.

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Force and torque induced by motions of a mobile manipulator effect dynamically to the objects being carried on it. If the induced inertia force and torque are bigger than the static friction force and torque, the carrying objects stary slipping motion on the mobile manipulator. As the result of it, the movement of carrying object may cause a collapse of all carrying objects, since a start of slipping makes the traveling acceleration of the mobile manipulator increase, furthermore it interferes with accurate traveling operations. A final purpose of this research is to propose a navigation controller of mobile manipulator that prevents the carrying objects from slipping. As a first step of this destination, we propose a model of n-link Power Wheeled Steering (PWS) mobile manipulator including the slipping motion of plural carrying objects. Using the proposed model, dynamical influences of the slipping are analyzed and the model is justified through several simulations.

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This paper describes a self-localization for indoor mobile robots based on integrating measurement values from multiple optical mouse sensors and a global camera. This paper consists of two parts. Firstly, we propose a dead-reckoning based on increments of the robot movements read directly from the floor using optical mouse sensors. Since the measurement values from multiple optical mouse sensors are compared to each other and only the reliable values are selected, accurate dead-reckoning can be realized compared with the conventional method based on increments of wheel rotations. Secondly, in order to realize robust localization, we propose a method of estimating position and orientation by integrating measured robot position (orientation information is not included) via global camera and dead-reckoning with the Kalman Filter.

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A speech-driven embodied entrainment character called “InterActor” with both functions of speaker and listener has been developed for activating human interaction by generating the whole body motions such as nodding, blinking and the actions of head, arms and waist coherently related to speech input. This paper demonstrates the effects of InterActor on interaction in human speech input by the analysis of speech temporal parameters. It is found that speech duration increases and speech activity decreases because of the increase of total silence duration and the number of silence parts in human-to-InterActor speech input, which is the advantage of real time processing for speech recognition and so forth. Interaction with InterActor is also highly evaluated in smoothness, enjoyment and preference by sensory evaluation.

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This paper deals with a human interface system for robot teleoperation. In robot teleoperation, it is very important that an operator can recognize an environment quickly and adequately. In this system, a reconstructed environment is constructed by distance data measured by some proximity sensors. Then, the reconstructed environment is simplified in order to teleoperate a robot by human. Additionally, this system can modify properly in consideration of environmental change. For showing the effectiveness of this method, we show some experimental results with small mobile robot “Khepera”.

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It is considered to be desirable that a wearable joint can be operated by human daily skills. In order to realize such a joint, the joint should be controlled so that the kinesthetic feeling induced by the kinetic characteristic of an object is directly, or transparently, transmitted to a person without any kinetic distortion by the joint itself, because it is considered that kinesthetic feeling induced by the object plays an important role in performance of the skills. This is the control issue of “kinesthetic transparency”. This paper proposes a control law to improve kinesthetic transparency of a wearable joint based on active compensation for the kinetic characteristic of the joint, and adaptive control is incorporated in order to eliminate necessity of off-line estimation for unknown kinetic parameters of the joint. Simulation results demonstrate that the proposed control law effectively improves kinesthetic transparency of the joint. However, experimental results reveal that more accurate compensation of frictional terms is necessary for further improvement of kinesthetic transparency.

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The effectiveness of jump model by mono-articular muscle and bi-articular muscle which imitated the human muscle arrangement was examined by the comparison of next three models. Models are (1) the serial link model in which two actuators of knee joint and ankle joint are independent, (2) the pantograph model in which two actuators receive the restraint by the biarticular muscle and (3) pantograph model which placed the actuator only in the knee joint. The effectiveness of jump model was theoretically verified from the static ground reaction force before the jump. The pantograph model (3) can jump only at the torque of extension muscle of the knee joint. In addition, the jump mechanism was produced experimentally, and the effectiveness of the model was verified. This conclusion is one of a solution to the general question too. “Why cruris of the animal which makes jump and high speed running good are very thinner than the femoral region”.

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This paper describes experimental studies of surface strain of a paper in a nip roller mechanics with a rubber-layered roller and a steel roller. It is important to investigate the strain of the paper surface in a nip roller mechanics for a precise prediction of the paper transport characteristics because the paper transportation of the nip roller mechanics depends on the strain of paper surface as well as the rubber deformation. First, an experimental setup of a nip roller mechanics with two short steel rollers was prepared. The velocity ratio between two steel rollers and that between the steel roller and the paper were measured for various normal forces. It was shown from experimental results that the in-plain paper deformation due to the normal force is vanishingly small. Next, an experimental setup of a nip roller mechanics with a short rubber-layered roller and a short steel roller was prepared. The velocity ratio between the rubber and steel rollers and that between the rubber roller and the paper were measured for various normal forces. Experimental reults demonstrated that the strain of paper surface greatly depends on the normal force. Moreover, by comparing the experimental results for two different rubber hardness, it was concluded that the strain of paper surface depends only on the nip width. Our shearing deformation model can describe experimental results well.

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This paper describes theoretical and experimental studies of the paper transportation characteristics of a long rubber-layered roller and a long steel roller. In a paper transport mechanism with long rollers, normal force distribution in the longitudinal direction arises due to the bending deformation of the roller core and the inequality of the clamping loads applied at both ends of the rollers. First, this normal force distribution was numerically analyzed by finite element method using calculated results of rubber deformation. Next, the friction drive characteristics between rubber and steel rollers was numerically analyzed. The velocity ratio between rubber and steel rollers was measured for various clamping loads experimentally. It was shown that the proposed analytical method can predict the velocity ratio between rubber and steel rollers precisely. Finally, the paper skewing due to the inequality of the clamping loads was numericaly analyzed. The paper skew angle was measured for various clamping loads experimentally. It was shown that the proposed analytical method can predict the paper skew angle precisely.

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The influence to ecosystem of plant by global warming is investigated. However, few diagnostic technologies by non-destructive inspection to environmental stress are established. Acoustic emission (AE) is applied to the measurement of damage under the water stress of plants. Cavitation phenomena are known by negative pressure under the lack of water in the vessel. Since shock wave due to cavitations issues AE, water stress state of plant can be monitored on real time by measuring AE. In this paper, AE events by the cavitation were measured in drought treated Ginkgo biloba I., Ficus spp. and Lycopersicon es. In all plant, AE events are increased during drought and stopped by supplying water. In Ginkgo and Ficus, a temporary decrease of AE events was observed during drought. It is presumed that plant adjust internal water balance for self defense by a certain procedure. Stoma closing of the leaf considered being the most effective physiology, however, was not the cause.

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In this paper, we researched the NRRO of an angular contact ball bearing for machine tools. At first, we developed a new apparatus for measuring rotational accuracy of rolling bearings. It was cleared the following results by measuring the radial NRRO used this apparatus. (1) The NRRO of cage rotation increased with rotational speed. (2) The influence of the shape error of inner and outer ring on NRRO was small. (3) The influence of the shape error and the diameter difference of balls were very big.

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The dispenser is used in various fields, such as semiconductor packaging, printed circuit board assembly, and electronic component assembly. While the miniaturization of an electric device progresses, the application with a highly precise dispensing is called for. In this paper, we propose the new dispenser of jet system, which consists of a screw pump and a piezoelectoric actuator in order to reply to the above-mentioned request. (1) For the proposed dispenser, theoretical analysis that calculates discharge pressure and flow late was carried out. The theoretical value of a pressure waveform showed good approximation to the experimental result. (2) Using high-viscosity and powdered fluids (the particle diameter are 0.8-10 μm), “Jet dispensing” experiment was done. We could jet the volume of 8 nl-20 nl/dot, dispense cycle is 5 msec (200 kHz) per dot, distance of a substrate and a nozzle is detached 1.5 mm and the speed of a stage is 300 mm/s. (3) The dispenser of this development can adjust the volume per dot by changing the number of rotations of a screw pump. As for the structure of this new type dispenser, high reliability is obtained for the stopped up prevention of the passage. The reason why is to be able to keep very bigger than particle diameter of 1-10 μm at any time as for the size of all passage.

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The present report describes a new method for numerical analysis of tooth forms of a shaved gear. It enables stock removals at shaving process to be evaluated from depth of cut of a shaving cutter to the shaved gear tooth. The depth of cut is calculated from an initial mismatch between teeth of the shaved gear and shaving cutter. Displacement of tooth of shaved gear and the cutter is due to forces acting on its flanks. The force is evaluated by volume of the initial mismatch. Meanwhile, the cutting performance is evaluated in consideration of sliding between flanks of shaved gear and the cutter. Developed computer simulation program includes these ideas and calculate the shaved forms which agreed with actual ones.

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For the purpose of the development of case-carburized gears for the high load carrying capacity, the relation between tooth surface-finishing method and surface durability of gear was studied. First, the surface qualities of ground roller, shot peened roller and shot peened and ground roller made of the hypoxia vacuum melting case-carburized alloy steel were examined by means of a acanning electron microscope and a penetrometer, etc. As the result, the effect of the shot peening on surface texture and surface hardness of the case-carburized alloy steel roller are clarified. Secondly, the surface durability of three kinds of roller was investigated by using a two-rollers-type contact fatigue testing machine. The following results are obtained : The influence of shot peening on failure, roughness and hardness of the rolling-sliding contact surface is found. The increase in surface hardness with shot peening does not always have an advantageous effect on surface durability.

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In this paper, the wear behavior of (Al, Ti) N fully coated tools was investigated when using two kinds of water-soluble cutting fluids for hobbing, which were compared with city water and dry cutting. Experiments were carried out using a fly tool. The results helped clarify the following points; (1) A water-soluble cutting fluid containing synthetic lubricating additive is effective for the flank wear, which is smaller than that obtained when using the city water only. The flank wear obtained with the dry cutting is smaller than that obtained with the water-soluble cutting fluids tested. (2) The fluid containing synthetic lubricating additive retards the occurrence of crater wear on the coated rake face in comparison with the dry cutting, and its crater wear ia also small. (3) It was suggested that the crater wear mechanism of fully coated tool is that first, the delamination and/or the seizure of the coating film caused by thermal fatigue occurs, and after appearing the substrate, the crater wear increased by the abrasive action with the cutting chips.

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In order to make clear the dynamic contact and adhesion forces of a magnetic head slider in near contact regime, we experimentally investigated the dynamic collision motion of hemispherical sliders on stationary magnetic disks. We used the hemispherical glass sliders of 1 and 2 mm in radius and the magnetic disks with different lubricant thickness of 0, 1, 2 and 3 nm with and without UV irradiation. As a result, we found that the dynamic adhesion forces of 1 and 2 mm radius sliders are almost equal to their static meniscus forces. In the case of 1 mm radius slider and 3 nm thick lubricant without UV, the dynamic adhesion force increases significantly because of a squeeze film effect. The 2 mm radius slider does not show a clear dynamic adhesion force at an impact velocity larger than 1.5 mm/s. We also found that contact force can be estimated by Hertz contact theory.

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Determining method of a coefficient of friction (hereafter coefficient) between tool flank and sheared surface in shearing is proposed. In the method, measuring of vertical force and horizontal force are needed at a stage after separation process completed. Then, the coefficient is defined as the ratio of vertical force versus horizontal force. The influences of punch speed, kinematics viscosity of lubricating oil and clearance on the coefficient were investigated. By the method proposed, the coefficient of about 0.35 was obtained when ordinary lubricating oil is used. The coefficient between tool face and material surface is also determined from sliding friction test. The results of FEM analysis in consideration of the coefficients obtained by the method showed good agreement with the experimental results of the piercing of small holes.

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Recently, vibration of machine tools has a serious problem, because it rough the surface of a work piece. In order to improve the structural properties of machine tools, we have developed a chatter restrained lathe for mirror finished surface. The optimum material for chatter restrained lathe was at first calculated by FEM simulation for vibration. In the simulation, lead was choosed for the optimum material of chatter restrained lathe. Therefore, availability of the lathe with both the tool post and the chuck using lead has investigated for machining mirror finished surface. It is concluded from the results that (1) The tool post and the chuck using lead have effect of restraining chatter. (2) The lathe with the tool post and the chuck using lead has low compliance, therefore the amplitude of vibration on the lathe is also small. (3) The new lathe is effective for improving surface roughness of a work piece.

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Non-coated normal drill generates long pitch helix type chip at the deeper drilling position than 7-8 times of drill diameter. TiN-coated normal drill has long tool life and lowers cutting resistance. However, it generates less long pitch helix type chip. TiN-coating decreases the long pitch helix type chip. Yet, it has been found that a TiN-coated twist drill which has narrow face of small rake angle shows good characteristics. The results are as follows : (1) The TiN-coated twist drill which has narrow face of 5-degree rake angle generates the long pitch helix type chip three times as much as the non-coated normal twist drill in 100 mm wet drilling. (2) And it generates the long pitch helix type chip which is connected with the conical helix type chip in 60 mm dry drilling. (3) The TiN-coated twist drill which has narrow face of 0 or 5-degree rake angle generates fragile chip that seems to be connected segment type chips with small area. These chips are exhausted out of the drilling hole very well. In case of these twist drills all chips are exhausted out of the drilling hole very well, the segment type chip occurs by fracture of this fragile chip after exhausting out of the drilling hole.

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This paper describes a diamond turning fabrication system for a sinusoidal grid surface, which is a superposition of periodic sinusoidal waves along the X- and Y-directions. The wavelength and amplitude of the sinusoidal wave in each direction are 100 μm and 100 nm, respectively. The fabrication system, based on fast-tool-servo (FTS), has the ability to generate the angle grid surface over an area of φ150 mm, This paper focuses on the improvement of the fabrication accuracy in local areas. Each of these areas is approximately 1 mm × 1 mm, which can be imaged by an interference microscope. Specific fabrication errors, caused by the round nose geometry of the diamond cutting tool and the data digitization, for the manufacturing process are successfully identified by Discrete Fourier Transform of the microscope images. Compensation processes are carried out to achieve a reduction of the errors. As a result, the fabrication errors in local areas of the angle grid surface are reduced to 1/10.

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A polishing pad has been playing a crucial role in conventional mirror polishing though many problems occur such as process instability, polishing non-uniformity and maintaining difficulties etc. Recently, a new mirror polishing method, which uses fine polymer particles, has been proposed and developed for overcoming the problems. At the same time, the feasibility of this new method when using oil as dispersion medium has been certified as well for polishing the materials unstable in water. In this paper, the tool plate, one of the most important elements in the new method, has been investigated to find an optimal type for the new polishing method when using oily slurries. Several kinds of tool plates have been discussed about the polishing characteristics and it is clear that the tool plate must have not only proper roughness and high rigidity, but also good affinity to the slurry. Furthermore a thin elastic layer covering on the surface of a hard tool plate is desirable. In addition, the urethane rubber plate with high hardness and tensile strength is the best one with relatively superior polishing characteristics, endurance and easiness of surface preparing among the discussed plates up to now.

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Shearing is one of the most important working methods in the manufacturing process, because it is repeated many times until the completion of the products. Therefore, it is very serious problem for the quality control of the products and the improvement of the productivity to evaluate the machining conditions. In this study, waveform analysis, wavelet transform analysis and chaos time series analysis were carried out to the detected AE signals during the shearing. And the extraction of the parameters for evaluating the machining conditions and the tool life was examined. As the results, it has been proved that the RA value of the time fluctuation waveform of wavelet coefficient and chaos time series analysis results are effective parameters for evaluating the conditions and the life. And the evaluation system using the RA value was proposed, and the validity of the system was confirmed by comparing the experimental results.

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Virtual machining simulator (VMSim) for flat end mill has been already developed so far, hence VMSim for ball end mill is developed in this research. This system consists of a geometric simulator and a physical simulator to evaluate machining process. The geometric simulator can calculate the changing geometry of workpiece and show the realistic shape machined by ball end mill including machining error due to the tool deformation. The physical simulator can also predict the instantaneous cutting force and machining error based on cutting models. The feasibility of VMSim is demonstrated in this paper.

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Multi-objective optimization (MOP) has been increasingly interested in supporting agile and flexible manufacturing in complex and global decision environment under diversified customer demands. To avoid stiffness and shortcomings of the conventional methods and to facilitate wide application of MOP in designing tasks, we proposed a flexible approach in this paper. It relies on the progressive modeling of intent or value system and the artificial system in an inter-related manner. The value system is modeled based on easy subjective judgments regarding preference on the alternatives while the system model involving a meta-model is described as responsive surface by the virtue of design of experiments. Beginning with building rough model for each, the approach can lead to the preferentially optimal solution gradually through correcting both models especially concentrated on the niche around the tentative solution. We have shown such approach can improve the complex and complicated design process while reducing the designer's load to express his/her preference. After explaining the proposed method in detail, effectiveness is examined through illustrative case studies.

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In this paper, a new genetic algorithm (GA) approach to simultaneous scheduling of processing machines and multiple-load automated guided vehicles (AGVs) is proposed. The proposed method is based on a GA for job shop scheduling problems. In the proposed method, a chromosome is composed of operation sequence genes and AGV assignment genes. Operation sequence genes contain processing operations, pickup operations and delivery operations. A decoding scheme considering processing and transportation is introduced. We applied the proposed method to a set of 82 problems which are designed to evaluate methods for simultaneous scheduling of machines and multiple-load AGVs. The result is compared with that of random search and schedule by using a dispatching rule. The proposed method outperforms random search in 54 out of 82 problems while the proposed method obtains better schedule than that of the dispatching rule in 31 out of 82 problems. These simulation results indicate the effectiveness of the proposed method.

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