Motion cueing methods of railway dynamic simulator for comfort evaluation experiments are discussed intended to reproduce measured cabin lateral motions of high-speed real vehicles at curves in the same scale. Motion cues to lateral and rolling directions are offline modified from the measured data by inserting a couple of high pass and low pass filters considering thresholds to rolling motion for low frequencies and complimentary inverse filters of identified frequency characteristics of simulator's motion actuators. The realized motion data at the simulator for the adjusted motion cues are calculated and experimented to show good consistence with the objected motion data in time history under the range of first resonance frequency of the simulator.

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Since there exists more or less sea current in most of underwater environments, ingenious guidance can lead an AUV to reach the terminal position with reduced consumption of fuel. This paper addresses the development of fuel-optimal guidance law and tracking control of AUV when it transfers between two pre-designated points in the sea region of environmental flow disturbances. Strategy of fuel-optimal guidance is applied to the navigation of an AUV "R-One", developed by IIS, university of Tokyo. In the formulation of this guidance problem, position vector of the vehicle relative to inertial frame is qualified as the state vector, while the vehicle's heading as the input. Total amount of fuel consumption to reach the terminal position is considered as the performance index. Optimal guidance law is formulated by the calculus of variations using the state-space model of system dynamics and performance index mentioned previously. Solution of the formulated problem is obtained by satisfying the necessary conditions called Euler-Lagrange equations, the solution of which minimizes performance index keeping the imposed constraints. Since the Euler-Lagrange equations leads to the two-point boundary value problem which is extremely difficult to solve, authors propose a numerical algorithm named "AREN" which always achieves the fuel-optimally guided navigation within a given current distribution. AREN detects the correct initial condition to draw out the numerical solution of optimal guidance problem, irrespective of the detailed profile of disturbance distribution. Simulations of optimal guidance of R-One in arbitrarily defined current distributions show as the current distributions become more complicated and diverse, gains by optimal guidance become more apparent.

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The magnetic levitation conveyance system is useful when we want to convey products without quality degradation due to contact. In this paper, we consider the magnetic levitation conveyance without the holizontal direction control to decrease the complexity and the cost of control system. We perform a modeling of the magnetic forces of controled vertical and uncontroled holizontal direction , and study the dynamical characteristics of this system by the numerical simulation and experiment.

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To enhance ride comfort in the superconducting Maglev system, vibrations were reduced by controlling secondary suspension between the car body and bogie. To reduce vibrations at the relatively high characteristic frequencies of primary suspension, attention has been directed toward control using power collection coils of the on-board distributed-type linear power-generator system. Because this control can apply damping directly to primary suspension, it is considered optimal in reducing high-frequency vibrations. Using a Maglev model focusing on vertical motions, this work describes the effectiveness of reducing vibrations using damping force control of the linear generator system in for primary suspension and LQ control in the actuators for secondary suspension.

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Magnetically levitated vehicle, so-called Maglev vehicle, is noticed as the next generation high-speed public transportation system. For the practical use, it is important to improve the ride comfort at high-speed operation. In this paper, the modal analysis by using the vehicle model,and the theoretical analysis of the vibration characteristic of the car body and bogie are inspected. Position of damper that is suitable for vibration mode, is evaluated in order to reduce the vibration. Moreover, the vibration control system for the ride comfort improvement is examined and effectiveness is confirmed.

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The combined type self-powered active vibration control systems, which produces control force using energy regenerated by dampers are applied to rubber-tired vehicle suspensions. To discuss its feasibility, the balance between the regenerated and the consumed energy is examined and the conditions under which regenerated energy is greater than consumed energy are obtained. Then control schemes of the self-powered system are presented and their performance are examined through numerical simulations. The results indicate that the system achieves active vibration control without external energy and its performance is as good as a typical active controller using external energy.

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A MSBS supports the model by both a permanent magnet and an electromagnet. Then, a permanent magnet can fill it up in the model as well. This MSBS doesn't have support interference effects because the model is supported by magnetic force and it can measure fluid mechanical power and moment acting on the model, so we can experiment in a wind tunnel ideally. The objective of this research is to: 1) set up a MSBS 2) evaluate a) fluid characteristics of self-excited vibration of the model due to the turbulence; b) vortex induced vibration; c) fluid characteristics of liquid by open loop transfer function; and 3) control this fluid vibration. Using this test, fluid force acting upon the sphere in water is evaluated.

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We are developing an electromagnetically levitated vibration isolationsystem for micro vibration isolation. It supports a floating isolationtable without any mechanical contact by using active magnetic bearings to reduce vibration from a floor. The system aims to regulate the microvibration in 6 degree of freedom. Two kinds of controller are designed and confirmed to levitate the table stably by experiments. A series of simulation show that the controllers have good effect on the vibration isolation.

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In order to realize perfect cleanness in semiconductor manufacturing process, we are developing a clean robot, in which the magnetic bearing is used for a joint of the robot. This paper mainly reports a new control method of magnetic levitation of the linear actuator in the clean robot that conveys a silicon wafer in a high vacuum clean room. As the linear arm of the actuator is flexible, the H infinity control method has been adopted for the levitation control and its performance is compared with that of PID. The gain-scheduling technique that changes a controller gain according the position of the arm has been introduced because of large change of distance between the center of gravity of the arm and the center of actuator in operation. The stable levitation and transference of the arm has been confirmed by experiments.

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The container crane of the harbor received the enormous damage in the Hanshin Awaji great earthquake. After that, the container crane with seismic vibration isolation system has been developed and operated in practical use. We proposed the rocking type of vibration isolation system (RVIS) for the container crane instead of the horizontal type of vibration isolation system that is used in bridges and buildings. In this paper, we propose the application of a semiactive control system to the RVIS mechanism to improve the isolation performance. The Kalman filter is used to estimate the system state values. The results of the isolation controlled by the semiactive system are better seismic isolation in performance than the passive RVIS.

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This paper describes a roller type isolation system for the individual showcases and individual works of art. The isolation system consists of two layers that form a XY-motion mechanism for two-dimensional horizontal motion; each layer consists of rails having a circular-linear-combined shape in the vertical cross-section to produce a restoring force, wheels, and fiction dampers comprising the wheels and the axles. Because the effective natural period of the system is independent of the mass, a long effective natural period can be achieved even for light equipment such as showcases. Shake table tests were carried out, showing good isolation performance of system and confirming validity of the analytical method.

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In this paper, we develop two springs using pseudoelastic SMA wire under vending deformation. One of them is called Ring-Type-Spring, and the other is called Buckling-Type-Spring. We also develop a base isolation device using these SMA springs. The response of the base isolation device with each SMA spring is investigated by experiment and equivalent linearization approach and it is clear that every spring has some damping effect. Especially, Buckling-Type-Spring restricts the transmissibility because of its characteristic of restoring force.

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In recent years, the relatively long period seismic waves have been observed in the various earthquakes, and the resonances of the high-rise buildings during earthquakes have been reported around the same time. Usually, the natural period of the isolation system is about 3 seconds, but it needed to be extended. Therefore we propose a super-long-period active seismic isolation system as a method for extending the natural period. In this paper, we designed a control system for it using the model-matching-method, and selected the optimum variables of transfer function using genetic algorithm.

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The purpose of the study is the stability analysis of dynamic buckling behavior of mechanical systems subjected to multi-directional excitations. A cylindrical structure with an attached mass on its tip is used in the analysis of the simplified model. The analysis is carried out by numerical simulations, where the horizontal and the vertical seismic loads are applied simultaneously. The combination of two loads are changed and the effects on the dynamical stability is investigated.

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When a thin walled cylindrical liquid storage tank is exposed to a very large seismic base excitation, buckling phenomena such as elephant foot bulge at the bottom portion and nonlinear ovaling vibration at the upper portion may be caused. In the previous study, elephant foot bulge phenomena and the liquid pressure effect were investigated. In this report, nonlinear ovaling vibration phenomena were investigated based on the dynamic buckling tests using scale models of thin cylindrical liquid storage tanks for the nuclear power plants. The mechanisms and the effect of vertical excitation and liquid sloshing were studied and discussed.

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By employing large scale shaking table, ultimate strength test was conducted for cable tray used in nuclear power plants. Test results revealed follows; (1)under S2 earthquake, damping ratio was so large, more than 30% due to rubbing phenomena of cables, that large response was not caused and support strains were under elastic limits (2)support had strength to sustain cable trays when support strains were 20 time larger than elastic strains. This report describes the results of shaking table test.

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In the seismic design of nuclear power plant, it is recently considered to use probability method in additon to certainty method. The latter method is to secure seismic safety of nuclear power plant by corroborating that calculated stress of equipment is lower than allowable stress of design criteria. And the former method, which is called Seismic Probability Safety Assessment (Seismic PSA) , is to secure seismic safety by corroborating that probability of reactor core failure is lower than a certain value. In Seismic PSA, it is important to estimate fragility of equipment for precise assessment; therefore, in this paper we dealt with a method using Bayesian Approach for generating a fragility curve and a design fragility curve from a multispecimen test.

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A semi-active seismic isolation system using a controllable friction damper was developed to decrease relative displacement between ground and a superstructure. However, if the controller of the controllable friction damper break down, it cannot demonstrate its full performance. A new controllable friction damper using dependable piezoelectric actuators is proposed to slove this problem. This damper has a fail-safe mechanism enabling the system to demonstrate damping effect in case of malfunctions. This paper outlines the results of the characterization experiments of this damper. It also reports the simulation results for the seismic isolation effect and the relative displacement reduction effect of semi-active seismic isolation system using this damper.

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This paper provides the experiments on semi-active control of a 3-story base-isolated structure using a magneto rheological (MR) damper. Three kinds of experiments were carried out for the following methods using the optimal control theory; (i)feedforward control method considering both time delay of MR damper and characteristics of earthquakes, (ii)feedforward control method considering characteristics of earthquakes only, and (iii)feedback control method. From the results of the experiments it was verified that MR damper could reduce acceleration and story drift responses of the structure in comparison with the case without any control. Among the adopted three control methods, the case (i) achieved the best performance.

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The first part of this paper deals with the dynamic characteristics of an MR damper and its analytical model. It is confirmed that the model simulates the experimental results by taking into consideration the second delay of the resistance to the control signal. Based on these results, the MR damper is installed in a seismically isolated structural model, and the usefulness of a hybrid semi-active control is verified by means of a series of shaking table tests. In this study, the term hybrid semi-active control means that both displacement and velocity dependent resistance are realized in the same damper.

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We have proposed a technique for SEA model construction using FEM, which is called FEM-SEA.Using this method, we can build the SEA model without actual experiment.The purpose of the reserch was building the FEM-SEA model for an automobile trimmedbody, which is whitebody with floor carpet. As a basic study, we examined the vibration character of steel plate with floor carpet.The result showed that a FEmodel consisting damped oscillator could describe the vibration of steel plate with floor carpet .Application of this FEmodel to actual parts of automobile clarified effectiveness of this model comparing with actual value.

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Automotive floor carpets are mainly effective to reduce noise radiated from the vibrating panel. Recently, the floor carpet is considered for reducing the vibration on the panel. This paper discusses the effect of attaching floor carpet on vibration and noise characteristics of a flat panel experimentally. As a result, it is suggested that the floor carpet reduces the out-plane vibration and gives the same effect as a viscous damping. We propose a FE modeling technique for the panel vibration including the effect of floor carpet based on the experimental discussions.

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The wavelet transform is expected to apply to the diagnostic technology for machines, as the transform can detect the local abnormalities of the signal. Then, it is necessary to remove the unacceptable noise in the wavelet transforms for the effective diagnosis. In this paper, we were able to detect the slight collision and the Coulomb friction by means of removing the noise from the waveforms which were limited to regular waveforms and abnormal signals were periodical. This paper presents the analytical procedure and discussions on the experimental results, and proves that the wavelet transforms is applicable to the diagnostic technology.

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Characterizing complex time series observed in the natural world is generally very difficult. Fourier analyses or wavelet analyses are often used for it but satisfactory results are hard to gain. One of the reasons of this is treating a compound signal as a single signal and separation of signals from the original will be needed in such cases. In this study, a short-term prediction method based on chaos theory is applied to feature extraction of complex time series. The prediction method is developed for predictive control method by the authors and the optimal sampling period is defined in it as one of important features of time series. The efficiency of the optimal sampling period as a feature for separation of time series is discussed fundamentally through numerical examples for a forced damped pendulum.

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This paper presents nonlinear vibration analysis of a clamped-clamped beam supported by a spring. The nonlinear strain-displacement relationship is employed and the in-plane displacement in the middle plane is included in the analytical model. The equations of motion are derived by applying the principle of virtual work. FEM-based equations of a beam with geometrical nonlinearity are derived, and a reduced-order model is obtained using non-classical modal coordinates. Transforming the equations of motion into the modal coordinates is defined by the displacement vector that is calculated from the nonlinear FEM-based equations. Using the reduced-order model, influence on nonlinear vibration of a spring support is studied in detail.

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The finite element method is used to investigate the steady-state vibration with the geometrical nonlinearity. The nonlinear strain-displacement relations are employed and the in-plane displacement in middle plane is included in the model. The equations of motion are derived by applying the principle of virtual work. Reduced-order model is derived by transforming the equations of motion from the physical coordinates to the modal coordinates that defined by the non-classical mode. We can obtain only a few d.o.f. equations of motion in the modal coordinates, and the present numerical results are compared with the results obtained by applying a numerical integration directly to the equations of motion in the physical coordinates.

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In order to obtain a highly accurate periodic solution for systems based on strongly quadratic nonlinear oscillators, an averaging method, which has been improved through the use of the Jacobian elliptic function, is proposed. In this averaging method, the Jacobian elliptic sine function is incorporated as the generating solution. The stability criterion for the approximate solutions obtained by this method is also presented. The efficiency of the proposed method is illustrated by comparing its computational results with those obtained by the shooting method and the conventional averaging method. It is confirmed that the proposed method provides a more accurate solution than the conventional averaging method, which uses a trigonometric function as the generating solution.

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Chaotic vibration is a very interesting phenomenon to our machinery dynamics researchers, and it may occur in many mechanical systems. An example is Duffing system in which many kinds of vibrations exist. In this paper, we deal with the chaotic vibration of a Duffing model, and apply OGY method to control the chaotic vibration. From the results we confirm the validity of our developed numerical method of calculating approximate discrete system around the neighborhood of a target unstable state from the continuous system for applying the OGY method.

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The algorithm of the Transfer Influence Coefficient Method (TICM) has extended to be available to free vibration analysis of a two-dimensional truss structure. The algorithm applies to only a tight joint. The new algorithm is presented for pined-joint as not limited of tight joint but usual truss structure. The new algorithm can be available to truss structure of tight joint or pined-joint by using some models. A free vibration analysis of some two dimensional truss structures is carried out by the new algorithm, which usefulness is showed by comparing this algorithm with usual one.

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Natural frequencies of a bending beam subjected to an axial force vary from the ones without the axial force. A compressive axial force exceeding a critical value leads the beam to a buckling. It is important to consider the effect of the axial force in truss and cable structures. The authors presented the Transfer Influence Coefficient Method, an advantageous method for dynamic response of structures but it didn't take the axial force into account for the bending motion. In this paper, a new algorithm of the Transfer Influence Coefficient Method to involve the effect of the axial forces is presented. Variation of natural frequencies according to axial forces and a buckling load of a beam structure are estimated by the newly presented algorithm.

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In this paper, we propose a method to approximate nonlinear ordinary differential equations to nonlinear retarded systems. Applying a parturbation method into a Duffingtype retarded system, we construct a primary approximation model. In order to improve accuracy of the model, we then modify system parameters of the model based on an averaging method to derive a modified approximation model. Errors among the original retarded system and the two models are evaluated. The modified primary approximation model results in the best approximation of the nonlinear retarded system.

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Belt is subjected to a speed limitation due to the occurance of resonance. In particular, a displacement impulse occurs each time the weld in steel belt initially contacts and separates from the wheel. The excitation is periodic, and it can excite instability. In this paper, we show that resonance occurs in the system when the weld passage(impulse) period is an integer multiple of natural period and propose a stabilization control method with internal resonance.

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While operating the contact rotating systems, a periodic polygonal deformation pattern is formed on the peripheral surface of a roll. Such phenomena is called the pattern formation phenomena. The occurrence mechanism of pattern formation phenomena for some contact rotating systems was clarified by regarding the cause of phenomena as the unstable vibration generated in a time delay system. Linear analysis is sufficiently effective in order to estimate the occurrence region of the unstable vibration. However, it is not possible to know behavior of large vibration, because the effect of the nonlinearity increases as the vibration grows. In this report, the authors add the adequate nonlinearity to cylindrical grinding systems and analyze the vibration behavior of the system. The harmonic balance method is used to calculate the periodic steady-state vibration approximately. In addition, the stability analyses of the periodic steady-state vibration are carried out from the characteristic exponents obtained from the variational equation. Furthermore, influence of initial condition and nonlinearity upon the vibration behavior was investigated.

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Vibration cutting is an effective method to cut materials with accuracy by generating pulsating cutting force, which arises while cutting speed is less than 2πaf(a : tool amplitude , f : frequency of the tool vibration ). If the cutting speed exceeds the value of 2πaf, called "critical cutting speed", the vibration cutting system usually becomes unstable. In this paper, we show that there is possibility that vibration cutting will process on the condition that cutting speed exceeds the critical cutting speed by numerical simulations. We classfy the dynamic behaviors in our model under four regions by using bifurcation diagram and lyapunov exponents. We show the phase trajectory and the cutting force in each region, and examine the peak-to-peak value of work displacement. The result suggests that there is possibility that vibration cutting will process on the conditions of exceeding critical cutting speed. This paper suggests that there is possibility of speeding up the cutting speed in the vibration cutting system.

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This paper describes the phenomenon called the inharmonicity for a struck string. It is known that its spectral components consist of two inharmonic peak series: 'first partials' whose generation mechanism is manifested and 'second partials'. Experimental tests for examining the mechanism of second partials were performed with a model of piano string. The experiments suggest that second partials are those that have frequencies equal to the sum of two normal first partials. Further numerical simulations were done by nonlinear wave equation involving large deflection of string.

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This paper describes that eigen frequencies for two dimensional beam structures under gravity. Because the beam structures were consisted of extremely thin flexible components,the shapes of the structures were changed due to their self-weight. And both ends of the beam structures were assumed to be clamped. To analyze these phenomena, discrete equations using finite element in consideration with geometrical nonlinearity were derived as cubic simultaneous nonlinear differential equations. First,large static deformations of the structures due to gravity were calculated using the proposed FEM. Next, linear natural frequencies for the deformed structures were investigated. The calculated results for straight beams and shallow arches using the FEM were consistent with the theoretical results carried by authors previously. Further,the influences of self-weight on eigen frequencies of the structure which was comprised of three straight beams were clarified.

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This paper describes identification of spatial modes in a chaotic vibration involving dynamic snap-through for a buckled beam witha concntrated mass. The beam is constrained by an axial elastic support and both ends of the beam are fixed. Using KL(Karhunen-Loeve) method, time histories are decomposed into components which have no corelation each other. Eigenvalues of covarriance matrix of the time histories correspond to contribution of the components to the original time history. The eigenvectors correspond to spatial modes(KL modes) in the chaos.The identified KL modes from numerical analysis were compared with the KL modes from experiment whichi was carried by the authors. Calculated results were consistent with experimental results in number of principal KL modes, shapes of KL modes, dimension,time histories,Fourier spectrum,linear natural frequencies and static restoring force.

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This paper presents an experiment on chaotic oscillation of a thin annular plate. The plate is clamped at internal boundary and is free along outer circumference. When the plate is subjected to periodic excitation, a large-amplitude response is generated by resonance. The time response is measured by a laser displacement sensor and is examined by the Poincare maps and the Lyapunov Exponent. Predominant response is confirmed to be chaos due to internal resonance. Furthermore, the time response of the plate is measured at four points simultaneously and principal components were obtained by the Karhunen-Loeve transformation. It is found that vibration mode of one nodal diameter and mode without node contribute to the chaotic oscillation. Principal component analysis for the short time period of the chaotic response shows that nodal lines in the first mode of vibration irregularly propagates to the circumferential direction, which suggests the existence of the traveling waves in the chaotic response of the annular plate.

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Nonlinear lateral vibration of a vertical cantilevered pipe with an end mass is studied for the case that the upper end of the pipe is excited periodically in a horizontal direction. The fluid velocity of an axial flow in the pipe is slightly over the critical value, above which lateral pipe vibration is self-excited by an internal flow. First, the effect of horizontal excitation on nonplanar flow-induced pipe vibration is examined by solving numerically the four first-order ordinary differential equations, which govern the amplitudes and phases of nonplanar pipe vibration and are coupled through the nonlinear terms. Second, the experiments were conducted with a silicon rubber pipe conveying water, and the spatial behaviors of the pipe were observed using two CCD cameras. The typical effect of horizontal excitation, which has been predicted in the theory, is confirmed qualitatively by experiment.

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Self-excited vibrations of a pipe conveying fluid with an asymmetric spring supported end are explored theoretically and experimentally. The planar, nonplanar vibrations and beating phenomena of the lateral pipe vibration are occurred due to the flow velocity and the perturbed parameter of the spring support. Furthermore, the experiments were conducted with a silicon rubber pipe conveying water. The spatial motions of the pipe were measured by the image processing system, which was based on the images from two CCD cameras. The features of the self-excited pipe vibrations, which were predicted in the theory, were confirmed qualitatively.

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This research deals with the fluid force acting on a sphere in a small-diameter tube. It is supposed that such a problem becomes very important when the small-diameter and complex fluid pipelines are designed in many systems of micro machines. The analytical model consists of incompressible viscous flow in a small-diameter tube at low Reynolds number, and spherical pendulum that can move almost perpendicular to the wall of the tube. After constracting the experimental setup in consideration of dynamical similarity, the fluid force acting on a sphere ,the displacement of a sphere, and the fluid velocity were measured by a loadcell, two optical displacement meters and the laser doppler velocimeter, respectively.

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One of the most important problems in an oil hydraulic system is the contamination problem. The aim of this study is to evaluate numerically the contamination of an oil. The measurement is carried out to evaluate a degraded oil using the ultrasonic sensor. As the ultrasonic wave propagates through a degraded oil, the energy of the ultrasound is scattered by the contaminant particle, and hence the some attenuation is occurred. This indicated that the attenuation of ultrasonic wave is closely connected with the distribution of each contamination particles.

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In oil refinery and chemical industry, electric -power industry, etc., aged facilities have been a serious problem. Especially, large-sized facilities, the solution is difficult. In order to solve this problem, we need two diagnostic technologies. One is the high-speed inspection technology of securing safety in the wide area, and another is the precise diagnostic technology of grasping a damage grade and a size correctly. The engineer belonging to facility management shall be utilized such technology well. Based on such an idea, the high-speed corrosion inspection technology that we are developing recently for a tank, a pressure vessel, etc. is reported.

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In chemical industry plant, electric power plant and so on, it is desired to operate under the condition with high safety as well as high efficient from an economical standpoint. For the performance of these conditions, it is required to well inform the present state of equipment of plant. These have been achieved by the machine diagnosis using vibration and/or AE techniques that, at present, have been utilized with respective uses. Each has the characteristic potential to diagnosis for machine conditions. It can be expected to improve the quality of diagnostics by making use of their characteristic features simultaneously.

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The integrated diagnostics technique developed makes it possible to evaluate the condition of equipments by multivariable patternrecognition applied to detecting signals which are obtained by transducers attached on the equipment to detect the abnormalitiesduring operation. The algorithm can synthetically evaluate the condition of equipments by a scale called "Maharanobis Distance". And also it can discriminate the each faults and malfunctions by the spectrum patterns.

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A three-dimensional shapes measuring system using an optical spatial modulator have been proposed. The system is composed of an optical spatial modulator from which grating patterns are projected on the surface of the object, a CCD camera controlled by a robot arm, and a computer. The patterns on the surface of the object were taken into the computer by the CCD camera, and the 3D coordinate of the surface of the object was calculated. The system was improved using mechanical and optical method and data analysis.

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In the line which rolls steel, aluminum, copper, the technique which measures tension of the plate is important for stabilizing the production. As the technique which measures the plate's tension, the vibration techniques required from plate's natural frequency are developed. The method for requiring from the relationship between tension and natural frequency becomes a basis. The method for combining amplitude distribution and attenuation characteristic, etc. is developed in order to raise the detection accuracy for the state of plate. In this study, the effect by the plate-type state did be not corrected from databases, etc., and the technique identified from the panel vibration directly was developed. In the support of the plate, it becomes a distribution in which the stress corresponds to the tension. However, the stress is eased near the plate longitudinal central by the rule of Saint-Venant, and it becomes a uniform distribution. Then, the tension value is calculated from one natural frequency, when the tension distribution is symmetrical. The mean value of tension value calculated from two each natural frequency becomes all tension, when it is asymmetric.

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We developed a non-contact temperature measuring system for running wires which operates with single heat flux sensor and no complicated calibration for various kinds of wire products. This system is believed to be useful to guarantee and improve the quality of wire products.

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This paper deals with measurement of particle flow by Gas-Solid suspensions flowing using the measurement of static electricity. The measurement of static electricity is effective in measuring flow of particles when they flow in small quantities at high velocities. We conducted experiments to confirm whether the quantities of flowing particles can be measured or not by measuring static electricity.

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In this paper, we measured the rotational speed of the spindle and the main shaft of the multi-drilling system to detect a trouble in cutting operation. We processed the rotational speed by the Wavelet analysis and reduced the effect of the gear transmission and noise. We also defined some characteristic parameters for the detection of trouble. Finally, our proposed technique showed the good detection ability.

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