This paper gives exact and global representation of all periodic solutions appearing in 1-DOF vibro-impacting system. The previously derived form of periodic solution by authors can be represented as superposition of periodic solution for linearized system and finite number of continuous periodic functions which is evaluated by equivalent impulsive responses caused by nonlinearity. However, it is not practical, because determination of impact velocities characterising periodic solutions includes infinite product and summation procedures in the form. To avoid this difficulties, relation between two types of representation of periodic solutions, traditional and newly one by authors, is reconsidered. As a result, it is clarified that transcendental equations for periodic connecting conditions in these representations can be mutually transformed by a pair of linear transformations. According to apply this fact, the finite product and summation scheme determining impact velocities of periodic solutions is derived.

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The contact problems between a rigid trolley and a pantograph in a current railway system are studied from the viewpoint of nonlinear dynamics. It is assumed that there are the impact oscillations between the rigid trolley and the pantograph due to the corrugated wear of the rigid trolley. The rigid trolley-pantograph system has been modeled with a spring-supported mass excited by an oscillating plate. Using this essential model, the influences of the car speed and the corrugated wear of the rigid trolley on the bouncing phenomena between the spring-supported mass and the oscillating plate were examined theoretically and numerically. Moreover, the experiments are conducted with the essential model, of which the motion takes place in a mechanically similar manner with the rigid trolley pantograph system.

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This paper presents nonlinear vibration analysis of a beam supported by springs. 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 steady-state vibrations of a curved beam with geometrical nonlinearity. The nonlinear strain-displacement relation is employed and the in-plane displacement in middle plane is included in the model. Equations of motion are derived by applying the principle of virtual work. A reduced-order model is derived by transforming the equations of motion from the physical coordinates to the modal coordinates on the pseudo-mode space. We can obtain only a few d.o.f. equations of motion in the modal coordinates, and present numerical results are compared with results obtained by applying a numerical integration directly to the equations of motion in the physical coordinates.

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Parametric excitations caused by mesh stiffness variation of multi-step gear system are analyzed using multiple time scales method and numerical analysis method based on fundamental solution matrix. As a result, the followings were made clear. (1) Influence of viscous damping was investigated, and it was pointed out that the analysis considering viscous damping was very important. (2) The differences of the results obtained by multiple time scales method and those by the numerical analysis method were large in the regions of combination instabilities which generate when the sum of natural frequencies is close to mesh stiffness variation frequency. On the other hand, in the primary resonances and secondary ones, the differences of those results were small generally. (3) In four-gear system, adding to primary, secondary, and combination parametric excitations, when difference of two mesh stiffness variation frequencies is close to natural frequency, or its twice, or the sum of natural frequencies, parametric resonance occur.

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In this paper, we propose a nonlinear vibration absorber for linear external resonance. This absorber does not utilize linear coupling to the main system but utilizes nonlinear coupling. Therefore, the attachment of the vibration absorber does not increase the number of degrees of freedom of the main system. Also, comparing with autoparametric vibration absorber, the proposed method is effective over wide range of the excitation frequency. By applying the method of multiple scales, the modulation equations of the main system and the absorber are derived. Comparison of the frequency response curves with and without nonlinear vibration absorber shows validity of the proposed absorber.

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Self-synchronized phenomena generated in rotor-type oscillators mounted on a straight-line spring-mass system are investigated experimentally and analytically. In the present study, we examine the occurrence region and pattern of self-synchronization in two types of coupled oscillators : rigidly coupled oscillators and elastically coupled oscillators. The experimental results for self-synchronization are qualitatively in good agreement with the numerical computational results obtained by applying the shooting method. It is clarified that the occurrence regions of stable solutions are governed mainly by the linear natural frequency of each spring-mass system. The results of numerical analysis confirm that the self-synchronized solutions of the elastically coupled oscillators correspond to those of the rigidly coupled oscillators. In addition, the results obtained in the present study are compared with the previously reported results for a metronome system and a moving apparatus and the differences between the rotor-type oscillators and the pendulum-type oscillators are shown in terms of the construction of branches of self-synchronized solution and the stability.

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In the previous report, the overall properties of self-synchronized phenomena generated in rotor-type self-excited oscillators were experimentally and analytically clarified using two types of system constructed from oscillators and coupled mass-blocks. The relationship between stable self-synchronized solutions and the linear natural frequencies of a spring-mass system in each system was also examined. For clarification of the occurrence mechanism, it is important to undertake an investigation that is based on the nonlinear vibration characteristics of the systems. Nonlinear normal modes have the potential to be useful tools for such an investigation, because the nonlinear normal modes and the self-synchronized phenomena are both periodic vibrations in nonlinear systems with many degrees of freedom. However, there is a very important difference, in that the former are free vibrations in conservative systems and the latter are self-excited vibrations in nonconservative systems, so that a definite relationship between them is not obvious. This report examines the relationship using the same systems treated in the previous report. Computational results demonstrate that many characteristics of the self-synchronized phenomena can be explained by the nonlinear normal modes.

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Stochastic jump phenomena in the random responses of a Duffing oscillator subjected to narrow band random excitation are investigated. The stochastic jump phenomena correspond to the existence of multiple stationary responses, as well as the nonlinear oscillator subjected to harmonic excitation. The Duffing oscillator subjected to the harmonic excitation has two stable stationary responses in some frequency range. These responses differ in the phase angle between the excitation and the response, as well as the amplitude. In the case of the stochastic excitation, there are two states of the response, and the jump between two states occurs suddenly and multiple times in the long sample function. These two states correspond to two stationary responses to the harmonic excitation. Amplitude and phase angle of each state of response are quite different when the stochastic excitation is narrow band, but the differences become obscurer when the band width of the excitation becomes broader. The purpose of this paper is to propose the criterion that is capable of distinguishing between two states of the response in the case of the broad band random excitation. In this study, we propose the product of each wavelet transform of the excitation and the response to estimate the phase angle between them. Numerical examples show that the product corresponds to the frequency decomposed phase angle between the excitation and the response, and successfully identifies the states of the response.

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Spatial behavior of a pipe conveying fluid is examined theoretically and experimentally under the condition that the pipe has an asymmetric spring supported end. The planar motion, nonplanar motion and beating, chaotic phenomena of the pipe vibration exist depending on the frequency of the pulsating flow velocity and the perturbed parameter of the spring coefficient. Furthermore the experiments were conducted with the silicon rubber pipe conveying water. The spatial displacements of the pipe were measured by the image processing system, which was based on the images from two CCD cameras. The typical features of the pipe vibrations, as predicted by the theory, were confirmed qualitatively.

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Analytical results are presented on nonlinear coupled vibrations of a clamped beam with a tip-mass constrained by an axial spring. First, governing equations of the thin beam are derived including both effects of the axial inertia force and the geometrical nonlinearity of the beam. The modified Galerkin procedure is applied to the governing equation by introducing a coordinate function for the axial displacement considering the quadratic nonlinear coupling with the deflection. Nonlinear periodic responses are calculated with the harmonic balance method. Frequency responses of the principal resonance of the fundamental vibration mode are compared by changing the mass attached to the beam end. When the mass is not attached to the beam, the frequency response agrees well with the result neglecting the axial inertia. As the mass is increased, the response curve in comparatively large amplitude shifts to the lower frequency range, owing to the axial inertia of the tip-mass. The analytical result of the frequency response, taking account of the axial inertia, agrees well with the relevant experimental result of a post-buckled beam formerly presented, which verifies our analytical results.

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Experimental results and analytical results are presented on chaotic oscillations of a suspended curved panel with square boundary. In the experiment, the panel is simply supported along all edges. The configuration of the panel is deformed by the gravity force and in-plane elastic constraint. Nonlinear periodic responses of the panel are examined under periodic lateral acceleration. Chaotic responses are observed and measured for modal inspection at four points of the panel simultaneously. In the analysis, the configuration of the panel is assumed as a suspended curved form with double arcs parallel to each edge. The Donnell type equation with lateral inertia force is introduced. The governing equation is reduced to nonlinear differential equations of a multiple-degree-of-freedom system by the Galerkin procedure. The nonlinear periodic responses are calculated by the harmonic balance method. The chaotic responses are numerically integrated by the Runge-Kutta-Gill method. The chaotic responses are inspected with the Fourier spectra, the Poincaré projections, the maximum Lyapunov exponents and the principal components by the Karhunen-Loéve-transformation. Both results of the experiment and the analysis show that the chaotic responses are generated within the frequency range of the same ratio to the each lowest natural-frequency. Poincaré projections of the both results coincide fairly well in detail. The number of modes generated in the chaos is counted as three by the maximum Lyapunov exponent and the Lyapunov dimension. The principal component analysis shows the predominant contribution of the lowest mode of vibration.

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This paper proposes a describing function method for limit cycle analysis of a system with a rate limiter. First, the rate limiter is defined and its describing function is derived in a strict manner.Then, the stability analysis using the describing function of the rate limiter is executed. In many cases of limit cycles, the output of the rate limiter becomes triangular, and in order to deal with such cases by the describing function, a new method to modify an open-loop transfer function is introduced. This method can predict the limit cycle occurrence more exactly, which is applicable to a prediction of a rate-limiter based PIO (Pilot-Induced Oscillation) of an aircraft.

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In this paper, we present an equation of motion for a motorcycle based on the multibody dynamics analysis assuming that the motorcycle consists of four rigid parts with nine degrees of freedom. In this model the cross-sectional shape of the tire is described as a half circle and its deformation is taken into account. Also by taking account of the slip condition or the nonslip condition of tires in longitudinal direction of wheels, the each equation of motion is derived. By carrying out simulations it is verified that the responses to the front-steering impulsive torque are in good agreement with those of a marketed software. Also longitudinal friction force and side force in the turning maneuver are shown.

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This paper presents a Jacobi-pseudospectral method with the weights of high-order gauss-lobatto formulae for nonlinear optimal control problem. This method employs Nth-degree Jacobi polynomial approximations for the state and control variables with the values of these variables at the Jacobi-Gauss-Lobatto (JGL) points as the expansion coefficients. The performance index may be approximated using the high-order gauss-lobatto formulae. The weights from this approximation is expressible explicitly in terms of the Jacobi polynomial. This process yields a nonlinear programming problem (NLP) with the state and control values at the JGL points as unknown NLP parameters. Numerical examples demonstrate that this method yields accurate results compare to analytic solutions.

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This paper proposes a model order reduction procedure based on nonlinear balanced truncation which preserves the port-Hamiltonian structure of the original model. This method allows us to preserve the energy variable which will be useful in controlling the reduced order model. Furthermore, a numerical simulation shows how the proposed method works.

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The dynamic characteristics of exhaust hangers for automotive use are studied for high frequencies at which the resonance vibration of the exhaust hangers occurs. A newly developed exhaust hanger composed of rubber and a thin metal ring is presented, which can provide a lower dynamic stiffness in a wide frequency range than an exhaust hanger made of solid rubber. A dynamic characterization testing and finite-element analysis of the exhaust hangers were carried out to clarify the frequency responses of dynamic stiffness in the high-frequency range. A method of treating the viscoelasticity of the rubber material using the finite-element method is proposed to predict the dynamic characteristics of the exhaust hangers. The finite-element method results show a good agreement with the experimental results for the frequency response of dynamic stiffness. Concerning the newly developed exhaust hanger, the effects of metal ring geometry and rubber hardness on the dynamic stiffness are examined to demonstrate the design principle for providing a low dynamic stiffness in a wide frequency range.

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Impact of spheres is one of the basic problems in mechanical dynamics. The severity of impact is generally characterized by the Coefficient of Restitution. The authors have already dealt with direct central impacts of two identical spheres in low speed impact and revealed that strain rate sensitivity of material properties could not be ignored even in low speed impacts. Therefore, this paper deals with the direct central impact of two identical spheres in high speed range. The experiments of direct central impact of two spheres were conducted by using steel balls for use in journal ball bearing (JIS SUJ2). Two steel balls were impacted by air gun. The impact analyses considering the material properties as well as the strain rate effect have been carried out using Finite Element Method (F. E. M). Then the experimental and analytical results were compared and they matched well. The effect of strain rate takes an important role in high speed impact as well as in low speed impact. If the strain rate effect of the material properties was ignored, it results in overestimation of inelastic work during impact in the numerical simulation. Further, it was found that the experimental equation for the coefficient of restitution derived from the experiments in low speed impact was still effective in high speed range.

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This paper investigates the sufficient conditions for self-identification of adaptive structure systems with the control input using variable structural parameters in the systems. The principle of the self-identification is explained by the effect of the control input on the eigen-values and eigenvectors of linear systems. Based on the principle and sensitivity analyses of modal properties, the sufficient conditions for self-identification are derived, where the controllability and observability of modal properties with respect to the control input are introduced. In numerical examples, two spring-mass systems with variable stiffness or variable mass parameters are examined. The results indicate that the self-identifiability of each system can be evaluated with the derived conditions.

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In this paper, we propose new controls and their design methods of driving force and Electric Power Steering (EPS). These controls enable to improve a vehicle lateral motion characteristics. First, Kinetic equations including characteristics of EPS system, vehicle lateral and longitudinal motions are clarified. Control-design policies are derived from their frequency responses. Then, we find that compensations of external disturbances and characteristics valiations are important, so driving force controller which compensates longiudinal and vertical disturbances at wheels and EPS controller which compensates vehicle lateral motion valiations and lateral disturbances at wheels are designed based on H-infinity control theory. Finally, their effectivenesses are shown by simulations and vehicle experimentations.

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In CNC Video Measuring System, very low speed motion is needed as well as high speed motion. Very low speed motion is highly influenced by friction. Currently, we use the PID Control with Look-up table gain to cope with this problem. However the process of developing this table tends to be a trial-and-error one. In this paper, we tried the Model-Based Controller Design. First, we made the model for control system design to use subspace method which is one of the algorithm in System Identification technique. Then, we designed the sliding mode controller with frequency shaped hyperplane and applied it to the real machine. Now we have achieved both the strong attenuation of disturbance in low frequency and the stability in high frequency using this technique.

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We propose a gain-scheduling control algorithm for locally stabilizing a discrete-time system with input saturation. The proposed control law has a structure that a high-gain control law and a low-gain control law are interpolated by using a single scheduling parameter. The scheduling parameter is computed on-line by solving a convex optimization problem with LMI constraints. By using the proposed scheduling algorithm, both feasibility of the algorithm and internal stability in the presence of computational delay and structured uncertainties are guaranteed.

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In the factory, the continuous steel plates subjected to iron and steel processes are supported by a series of rollers during processes such as rolling. However, because roller comes in contact with the steel plates, the problem of surface quality deterioration arises. To solve this problem, we develop a non-contact guide for parts of the steel plate at which its traveling direction changes in high-speed traveling by applying an electromagnetic force from the direction of the edge of the steel plate, and experimentally examine the effectiveness of the system. Moreover, when the position of the plate is controlled, it is extremely difficult to determine the mass of the control target. We confirm the suppressive effect of a sliding mode control theory that has robustness in mass variation. The results indicate that the proposed system can be achieved.

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This paper deals with model following control of a twin-rotor type model helicopter. The online parameter estimation technique is introduced to improve the control performance. The integral type of the estimation model is proposed for parameter identification since the derivative type of the model cannot obtain the desired estimation result. The experimental results show the effectiveness of the proposed method.

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In this paper, noise from a moving source on the road with sound insulation wall is studied. The noise diffracts on the upper edge of the wall and arrives at the evaluation point Q. Firstly, the noise source is placed at point Q, and the sound pressures are measured at point A and B on a line L which is regarded as the moving track on road. From the measured sound pressures, the transfer functions between the noise source at point Q and the point A and B are determined. The method to interpolate the transfer function at an arbitrary point on the line L between A and B is proposed in this study. Using the reciprocity theorem and the interpolated transfer function, it is able to predict the noise arrived at the evaluation point S from the moving source on the line L.

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Heat storage type of electric water heater has a practical useful aspect. But it is still necessary to reduce the noise at boiling and to add the function of rapid heat storage. Therefore, a new heating method is proposed where both the main heater installed at the bottom and the sub one installed at the top are used. We examined in detail the basic characteristics of two heaters for heat storage and the noise when using them. Experimental results show that the duration time for rapid heat storage can be diminished to 1/4 and the noise can be reduced by 17 dB. It is found that this proposed method is useful for industrial application.

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A two-dimensional microphone array is necessary to realize instantaneous measurements of sound fields. The array has a skeleton to hold many microphones, and the skeleton should be located near sound sources when the results of the measurements are applied to the method of nearfield acoustic holography. When spacings between the microphones would be small for a fine spatial resolution, bodies of microphones are approaching each other. In such a condition, sound waves reflected at the surfaces of the structure would become easier to reach to the microphones for measurements. As a result, measured distributions would be distorted by such disturbances. In this paper, an experimental procedure to investigate the effects of the array structure to the sound field is proposed. An actual array structure was constructed, and the effects added as deviations on the true values of complex sound pressures are measured experimentally with a scanning microphone. Then, relative complex deviations involved in the complex sound pressures are calculated and shown to evaluate the effects. Locations of reflecting surfaces that would cause the deviations are discussed with the values of lagged distances derived from the relative phase distributions. The methodology and results summarized in this paper would be worthy to develop the analysis to investigate the actual insertion effects of the array structure to the analytical applications such as the NAH.

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At present, many products are demanded both facilities and comforts. It is necessary for realizing comforts to measure human sensitivities. Therefore, many various sensory evaluation methods are proposed. Scheffe's paired comparison is one of these sensory evaluation methods, and is used widely. Especially, Nakaya's method, that is developed based on Schffe's paired comparison, evaluates human sensitivities and enables to add a relative score to the samples. However, the conventional Nakaya's method can separate the main effects, differences among individuals and combination effects. If there will be other factors that have an effect on the samples' evaluation, the effects will be neglected in Nakaya's method. Therefore the main effect tends to be hard to be detected by Nakaya's method. In this paper, we propose a new sensory evaluation method that enables to separate multiple effects. As this new method enables separate many effects, the relative error variance value is smaller, and it will make us to search factors easily and correctly that affect human sensitivities. This new method is applied to the loudspeakers' psycho-acoustic evaluation, and it is clarified this new method is useful for sensory evaluation when the difference is small and when there are a few panelists.

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In this study, we propose a new type of complex wavelet, named Motion Wavelet. The shape of the Motion Wavelet is changed according to a certain reference signal, and its variable wavelet transforms another target signal, which is therefore picked out the variable frequency elements according to the reference signal. These relational transforms can be applied to making new entertainment sounds. For example, if we adopt a voice of a speaking as the reference signal and many kind of signals -such as cries of animals, sounds of musical instruments and other nature sounds- as the target signal, we can get interesting and illusionary entertainment sounds which sound as if the animals spoke human words, the musical instruments sang a song and so on.

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We developed a new type of nutation motor without using air pressure, named the electromagnetic nutation motor consisting of some electromagnets and the OF1 (Output gear Fixed) type bevel gears (a nutant bevel gear and a fixed bevel gear). Driving each electromagnet sequentially causes nutation of the nutant bevel gear, which makes the output shaft rotate through universal joint and spherical bearing. In this report, first, the driving principle and design of this motor are presented. Next, the optimal shape of the electromagnet is found using the finite element method (FEM). Using this electromagnet, the prototype of electromagnetic nutation motor is fabricated and tested. As a result, it is confirmed that this motor has a maximum torque of 0.87 N·m, a maximum rotation of 4.3 r/min, and a minimum resolution of 1 248 step/rev.

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Recently, robots attract attention as a work force in the dangerous and severe environment. Especially, legged robots are extensively researched for the use in such environment. In such environment, it is necessary for the legged robot working to have fault tolerance and adaptability to environment. There are two reasons. The first is that road condition is not maintained by human. The second is that it is difficult to repair robots. In this paper, a gait generating network with fault tolerant, adaptability to irregular terrain and decentralized system are applied to a hexapod robot. In the proposed method, a new network is generated when one of the legs is broken and a new gait is produced with new network which consists of the remaining legs. The method is applied to hexapod robot and experimental simulation is conducted. The generation of gait when walking in slopes and walking with one deficient leg is confirmed.

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In this paper, an intelligent visual evaluation system using a neural network is developed in order to evaluate the barrel finished surfaces. It is well known that the surface integrity after barrel finishing depends on type of finishing machines, nature of the media and the compounds. The integrity of barrel finished surfaces, when different compounds were used, have typically been evaluated by visual inspection of expert workers. It is necessary to introduce the optical qualitative evaluation system instead of visual inspection in an automated inspection line. However, it is very difficult to evaluate the finished surface using image processing and/or other measuring equipment, because of complexity of data analyses for slightly different light reflection data among each finishing condition. As a result, not many papers have been published on the optical evaluation system for the barrel finished surfaces when different compounds were used. The objectives of the paper are to analyze the image of barrel finished surfaces using image processing, and to construct a neural network system which is able to evaluate the finished surface integrity. In this paper, it is found that features of barrel finished surfaces are decided by image analyses. As a result, it is possible to construct a neural network system composed of the finished surface image features as input layer and grades by the sensory test as output layer.

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It is experimentally known that a flat surface vibrating at ultrasonic frequencies generates forces in both vertical and parallel directions to a vibrating surface, and these forces can support a floating object without any contact. However, the cause of the force parallel to the vibrating surface (called a holding force in this paper) has not been clarified yet. Therefore, this paper investigates the cause of the parallel force generated by a vibrating surface, experimentally and numerically. In numerical calculations, computational fluid dynamics (CFD) was used in order to obtain the pressure distribution of air surrounding a floating object and a vibrating plate. It was consequently found that the holding force acting to a floating object is due to an average minus pressure generated at the edge of a floating object on the vibrating flat surface.

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Spalling and Scuffing are well known as the failure pattern of case-carburized gear. Micropitting was recently recognized as a failure too and already became a problem. Micropitting is very small failure on the contact surface. Despite of its size, it can lead, by accumulating, to several failures such as frosting or fatigue scuffing. In this study, the authors investigated the occurrence of micropitting and its tendency to increase in quantity. A disk machine with rolling and sliding was used. Fatigue tests were carried out with carburized SCM420 steel rollers and SCM420 steel rollers shot peened by two different methods ; ultrasonic shot peening and air shot peening. Micropitting was generated by load around 1/4 of the load that causes spalling. Quantity of micropitting increased as the number of cycles increased. Micropitting was observed in the faster test roller and its amount was less than the slower side. S-N curve was obtained from the fatigue life, which is assumed as the number of cycles in which the micropitting area reaches 5%. As a result, the influence of the surface roughness seems to be large in the fatigue life of the micropitting.

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The rolling contact fatigue of crowned rollers made of bearing steel SUJ2 was investigated with a two-roller test machine under a sliding-rolling contact condition with oil lubricant. The nominal crowning radii of the rollers were 110 mm, 90 mm and 60 mm. The roller was mated with a non-crowned roller or a roller with a concave crowning radius of 110 mm. The contact pressure and subsurface stress were analyzed with three dimensional FEM. Within the applied load in this experiment no edge loading or minor edge loading occurred in the crowned rollers mated with the non-crowned roller and major edge loading occurred in the crowned rollers mated with the concave crowned roller. In case that no edge loading or minor edge loading occurred, the failure mode of the rollers were pitting caused by surface cracking and the rolling contact fatigue strength evaluated with the normal load increased with increasing crowning radius. In case that the edge loading was great, the failure mode of the rollers tended to be spalling caused by subsurface cracking and the influence of the crowning radius on the rolling contact fatigue strength was little.

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Diamond-Like carbon (DLC) films have been widely recognized as a tribo-coating material because of its outstanding mechanical properties. Theses properties are varied according to their preparation method and condition. In order to apply DLC films to industrial products, an appropriate film for an environmental condition should be prepared by a proper coating method. Furthermore, requirements for films are increasing recently. For example, resistance to adhesion, chemical stability, gas impermeability and water repellency are required in addition to the tribological properties. The objective of this study is a development of a multi-functionalized DLC film using segment-structured DLC (S-DLC) films. S-DLC film is a useful coating method for soft substrate. It consists of numeral small DLC segments and has grooves between the segments, which is different from the conventional continuous DLC film. In this study, a developed S-DLC film is proposed. It has fluorocarbon polymer embedded into the groove, which can improve the water repellency and lubricating ability of S-DLC film. Its tribological properties and water repellency were estimated by ball on disk tests and the contact angle of a water droplet, respectively. The friction coefficient of 0.08 is obtained, that is lower than 0.12 of continuous DLC film. The contact angle of a water droplet can be obtained about 90 degree, which is larger than 60 degree of a continuous film. From these results, multi-functionalized DLC films could have been successfully fabricated.

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The motion characteristics of a slipper bearing in the swash plate type piston pump and motor have been investigated experimentally and theoretically. The motion of the slipper bearing has been measured by means of eddy current displacement sensors. The mathematical model of the slipper bearing has been indicated considering asperity contacts of surface roughness, comparing experimental results. It is found that (1) the numerical calculation results correspond to experimental ones, (2) the slipper bearing may swing at the same cycle as rotation of the swash plate, (3) the motion of the slipper bearing in pumping action differs greatly from that in motoring action, and (4) the friction phenomena between the cylinder and the piston, and on the spherical bearing affect on the motion of the slipper bearing.

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The mechanical behaviors of bolted joints with PTFE gasket have been evaluated by taking visco-elastic-plastic properties of the gasket into account. The strain-time equation of the gasket under multi-step unloading has been proposed by conducting the compression tests with loading and unloading, creep tests and creep-relaxation tests. By applying the equation, the analytical model which can calculate the variations in axial bolt loads for a joint tightened by single bolt has been also developed. The bolt load relaxation tests under some different gasket contact stresses have been performed for the single bolted joint. As a result, it has been observed that the developed analytical model could reproduce the bolt load variations within accuracy of 10%. Furthermore, the finite element model using the strain-time equation of the gasket has been proposed to simulate the bolt load relaxation and time variation of gasket contact stress of a pipe flange connection. By comparing to experimental results, it has been confirmed that the developed FE model can simulate the bolt loads relaxation with accuracy enough for practically. The gasket contact stresses have been evaluated numerically, and it has been concluded that the examination including the gasket viscous properties are very important.

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This study aims at making a small billet for micro forging from sheet metals. Disk specimens were made form 2 mm thick aluminum sheets and extruded in the thickness direction at an extrusion ratio of 2. A billet of 1 mm in diameter was successfully formed on the specimen and the billet height varied from 2 to 5 mm depending on constraining conditions of specimen. The highest billet was obtained when the specimen was extruded with both the top and side faces constrained. Diameter of specimen also affected the billet height in the case of no constraint in the radial direction. Deformation behavior was studied by FE analysis and difference in metal flow by the constraining conditions was clarified. Strain distributions showed that deformation became severe toward the bottom of the billet. Piping defects that occurred in the end of forming were also predicted. Calculated billet heights agreed well with the measured ones.

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Because of design of aisles in facility layout affects material handling of workshops, considering material handling aisle is absolutely essential. However, many of previous researches don't consider material handling aisle, a few of researches considering it make dead space huge and can't make shape of workshop fixed. These led to unreality on facility layout. In this paper, we suggested Force Directed Component Placement and movement of workshops group considering material handling of workshops. In addition, we minimized the material handling cost and the purchasing land cost considering the material handling aisles.

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