The optimal design problem of free vibration is solved for laminated composite shallow shells of rectangular planform. The shelts have symmetric laminated construction and are supported by shear diaphragms along the edges. The first-order transverse shear deformation is assumed in the Donnell type shell theory to account for the thickness shear effect, and an approximate solution is presented for angle-ply laminates. A simplified formula is derived by neglecting inplane and rotational inertia terms. Analytical solutions with/without the inplane inertia terms from the classical thin shell theory are also shown. In numerical examples for two types of shell curvatures, e.g., circular cylindrical and spherical shells, fiber orientation angles which cause the maximized fundamental frequencies of the alternating angle-ply shells are determined, and effects of using the four different vibration solutions are discussed on the optimal frequencies and fiber orientation angles.

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An exact solution procedure making use of a transfer matrix method is presented for solving out-of-plane vibrations of a connecting system composed of multiple straight and curved bars. The field and the point transfer matrices are formulated by using the exact solutions for each equation of motion of the straight and the curved bars. As numerical examples, frequencies for U-bars of semielliptic and straight bars are presented and the reliability and the availability of the present method are discussed.

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For the free vibration of a laminated FRP (fiber reinforced plastic) composite plate, the authors proposed a numerical approach using the functions for a static bending problem. By this approach, one can accurately estimate the natural frequency and mode shape of plates with various shapes and boundary conditions. In the present paper, this approach is modified for application to a cross ply laminated shallow cylindrical shell of rectangular planform. First, numerical calculations are carried out for a clamped symmetric cross ply laminated shallow cylindrical shell of square plan-form. The convergence of natural frequency of the shell are discussed. The effects of the layer material and the number of layers on the natural frequencies and mode shapes of the shell are numerically investigated. Next, by the vibration tests of clamped symmetric cross ply laminated shallowcylindrical shell of square planform, natural frequencies and mode shapes are obtained. From the comparison between experimental and numerical results, it follows that one can accurately estimate the natural frequency and mode shape using the numerical approach proposed by the authors.

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This paper deals with steady-state response of the continuous system with nonlinear support having hysteresis damping characteristiCS. Considering the energy loss for hysteresis of spring constant of support, an analytical method of approximate solution for the nonlinear response of the beam with quadrilateral hysteresis loop characteristics is presented. Some numerical results of the approximate solution for the response of the system and the mode shapes are shown. The objectives of this paper are to present the approximate steady-state solution of the continuous system with nonlinear support under harmonic excitation and to illustrate the numerical results of approximate solution.

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The finite difference method is applied to calculate the non Gaussian probability density function of a single DOF nonlinear system subjected to white noise excitation. The probability density function is governed by linear partial differential equation known as the Fokker-Planck equation. The standard finite difference method is not necessarily suitable for the Fokker-Planck equation, since the 1st order upwind difference needs a large number of nodal points and computation time, and the conventional higher order upwind difference and centered difference may cause negative probability. Therefore the 2nd order upwind difference is modified in order to avoid negativeprobability and employed for the drift terms of the Fokker Planck equation. The present scheme also satisfies conservation property, i.e., total probability always equal to One. The stationary joint probability densities of a Duffing and a Van der PoI oscillator are calculated and compared with the exact solution or Monte Carlo simulation results.

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The finite difference method is applied to calculate the non-Gaussian probability density function of a single DOF hysteretic system subjected to white noise excitation. The probability density function is governed by linear partial differential equation known as the Fokker Planck equation. In the 1st report, we pointed out that the standard finite difference method is not necessarily suitable for the Fokker Planck equation, and presented the modified 2nd order upwind finite difference method for the drift terms of the Fokker-Planck equation. The modified scheme satisfies fundamental property of probability density, i.e., the solutions are non negative and total probability equals to one. In the present report, the scheme is applied for the transient responses and stationary joint probabib ity densities of a single DOF hysteretic system and compared with the Monte Carlo simulation results.

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The Jeffcott rotor is the most widely used theoretical model in the analysis of rotor systems. This model satisfies the condition of 1: (-1) internal resonance, and we clarified the effect of this internal resonance on nonlinear steady-state oscillations at the major, twice the major and three times the major critical speeds in the previous papers. In this study, we investigate nonstationary oscillations during acceleration through the major critical speed in the Jeffcott rotor and other rotor systems which almost but not exactly satisfy 1: (-1) internal resonance relation. Especially, we pay attention to the influence of internal resonance. The foilowing are clarified theoretically and experimentally: (a) Nonstationary oscillations of the Jeffcott rotor and other rotor systems whose natural frequencies almost satisfy 1: (-1) internal resonance relation are influenced by the internal resonance. (b) It is easier to pass the major critical speed of a rotor system with internal resonance than that of a rotor system with no internal resonance. (c) When the system has slight discrepancies among critical speeds, that is, almost but not exactly satisfies the relation of internal resonance, the rotor can pass the major critical speed very easily with small amplitude even if the acceleration is small.

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Non stationary responses of a vertical Jeffcott rotor contacting with an annular guard during passage through a critical speed accelerated by a power limited motor are calculated and their characteristics are investigated. The results show that (1) three typical rotor whirl patterns are observed, that is, contacting forward whirl, backward whirl of contact/collision type, (2) the backward whirl of contact type shows large displacement and large contact force, (3) the increase in coefficient of friction and mass and stiffness of annular guard system accelerates development of the backward whirl, while the increase in eccentricity and contact stiffness has an opposite effect, and (4) the balance of forces in each rotor whirl pattern is clarified.

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This paper deals with a rotor balancing method based on influence coefficient method and LMI (Linear Matrix Inequality) optimization technique. The three rotor balancing objectives; (a) minimization of maximum residual vibration, (b) minimization of the least mean square of residual vibration and (c) minimization of the least mean square of correction masses, are considered. Since the conventional influence coefficient method cannot properly treat the objectives (a) and (c), these objectives (a) and (c) have been considered by heuristic trial & error method. In this paper, first, the LMI formulation of the rotor balancing objectives (a)-(c) are derived applying two basic LMI lemmas. Based on these LMI formulation of the objectives, a LMI optimization framework for rotor balancing is then constructed. The proposed method enables us to efficiently achieve the objectives (a)-(c) with the relative weight vector c using LMI optimization technique. Moreover, a reduction algorithm for the number of the correction planes, which is useful in the actual field balancing, is also considered. Finally, the effectiveness of the proposed rotor balancing method is evaluated by numerical simulations and experiments with a model rotor system.

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This paper deals with self excited oscillations of the structure coupled with inner fluid occurred in the insulation wail cooling system of fast breeder reactor Super-Phenix-1 (SPX-1) in France during test operations. We analyzed and performed experiments on the instability of multiple cylindrical structure system which has dual flexible weir shells. We measured self excited oscillations changing various parameters such as discharge flow rate, gap of the liquid height between feeding and restitution plenums. In the experiment, it was found out that dual cylindrical shells oscillate in the inverse phase each other with an oval vibration mode under the specific conditions. Comparison between theoretically and experimentally obtained instability region was made, which shows good agreement.

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System identification is one of the key technologies to predict accurately dynamic behavior of space structures. We must solve a linear simultaneous equation to identify the mass matrix and stiffness matrix of the structures. An exact solution can not be necessarily found because the coefficient matrix in the equation is ill-conditioned. The singular value decomposition is applied to obtain an approximate solution. This paper proposes a method to use the projected power as an indicator for determining how many singular values should be considered. A numerical example is given to show that the proposed method is effective for system identification. It is found that the identified mass and stiffness matrices can provide a highly accurate finite-element model mating with both vibration test and mass property test results.

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This paper describes an approach to the identification of a time-varying transfer function which represents the instantaneous frequency response of a linear time-varying system. It is shown that the identification problem of the time varying transfer function is equivalent to the estimation problem of the nonstationary cross-spectrum between the output process and the appropreately filtered input process. According to this fact, we propose a three step identification procedure which includes two nonstationary spectral estimators. The identification error is asymptotically evaluated and numerical examples are examined to illustrate the performance of the proposed method.

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In this paper, we discuss dynamic stability of a flow conveying pipe with a lumped mass by using boundary element method for a regional division type. We already showed the applicability of the numerical method for dynamic stability analysis of an elastic rod with damping terms. Our derivation of integral equations is based on an inverse formulation of a canonical form. The boundary integral equation is derived for each partial region. A coefficient matrix of a whole system obtained from the resulting discretized form possesses a band type sparse property. We apply this method to dynamic stability analysis of a flow conveying pipe with a lumped mass system. Moreover, our system includes damping terms in connection with internal and external damping effects. Our numerical results of the problem demonstrates a sufficient accuracy through a comparison with other results. Therefore, we are sure that our method give a powerful means for this tpe of problems.

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In this paper, we propose a method to give models of complex systems for controller design by using numerical simulators. We apply this method to a two-dimensional region simulator for blast furnace and show a process of leading a model for control. Furthermore we compare the dynamics of the model with the simulator and analyze the performance of this method.

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The small displacement control of large electric-hydraulic servo system is effected severely by cylinder friction, specially on long oil-height of cylinder. So, we analyzed the effects of cylinder friction to its response. These results were confirmed by experiments of real scale equipment of rolling mill. And, we approximated the effect of friction and oil-height for response with dead time and will use it in following study.

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In this paper, a new theory for cross orthogonality check between analytical and experimental modal vectors based on a General Definition of Projectors is described. Since this cross orthogonality check can be computed without a mass matrix, this method is easier to use and saves remarkably efforts to perform cross orthogonality checks. In addition, this cross orthogonality check can be applied even if the modal vectors are complex. Hence, we estimate the cross orthogonality among experimentally determined modal vectors, and there are many possible applications in experimental modal analysis. Moreover, a new theory for coordinate cross orthogonality check method based on the orthogonality check is proposed. This coordinate cross orthogonality check can quantify the correlation of the modal displacements for a given degree of freedom without a mass matriX. This paper introduces the theory and demonstrates the validity on numerical models. The results show that these checks are sufficiently reliable to estimate the difference between analytical and experimental modal vectors.

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This paper describes the performance of lateral mechanical guidance system for Dual Mode Truck. The vehicle stability is analyzed by 10 DOF vehicle dynamic model, where the coupling effect of the steering system with the hydraulic power steering device and the mechanical guidance system is considered. The unstable motion that is occurred in the field test with actual prototype Dual Mode Truck is analyzed with the simulation study. Both the simulation study and the field test show that the power steering device has large influence on vehicle stability and the unstable motion can be suppressed by cutting off the power steering device in the guideway. It is also shown that high speed operation of the Dual Mode Truck can be performed without power steering function in the exclusive guideway.

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This paper deals with modeling and analysis of an impact system, which is composed of ball and plane. An impact model considering both duration of impact and energy ioss is proposed. The Resultant force due to impact is formulated by introducing a complex stiffness coefficient in Hertz's contact theory. From the expression for the resultant force, the impact system is modeled by both a nonlinear spring and a nonlinear dashpot. The characteristics of the nonlinear spring is expressed by using Hertz's theory, and that of the nonlinear dashpot is expressed by a function of the displacement and the velocity. The model parameters are determined by the configuration, the material value and the coefficient of restitution in the impact system. Experiment and simulation are carried out to demonstrate the accuracy of the proposed model, and good agreement is shown.

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A six-degree-of-freedom model and a twelve-degree-of freedom model incorporating a rider's vibrational characteristics have been developed. The models include a mechanical model of the rider's body which consists of a leaning motion of the upper body and a lateral movement of the lower body. Damping properties and natural frequencies of weave and wobble modes were calculated using these models. Conclusions are drawn about effects of the rider's vibrational characteristics on the stability of motorcycles during straight running from the calculations in the six degree of freedom model. Implications for accurate modeling of motorcycle stability are derived from differences between the calculations in the twelve-degree-of-freedom model and running experiments.

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In this paper, the calculation method is presented for estimating the transmission level through a bolted plate, utilizing a coupled acoustic structural analysis of Finite Element Method. And the calculation method is presented for estimating the transmission level by mass spring model which is equivalent with circular plate. In a flexible panel its own sound radiation, caused by the sound induced vibration, often increases its transmissibility significantly. Presented modeling technique incorporates the sound radiation and the conventional Transmission Loss for the better estimation of sound through a panel. Also the rotational stiffness of the bolts are included for the accurate finite element modeling of a flexible plate. As a numerical example, a circular plate with bolted edge is investigated, and the calculated transrnission level shows good agreement with the measured result.

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Flexibility of payload mount in inertial stabilization system often exists, partly because nonrigid drive mechanism, support and/or platform, and partly because inserted vibration isolator. The mount flexibility, however, can cause severe instability of the stabilization control system, and thus introduces an adverse effect on system performance. This paper analytically reveals the mechanism of instability caused by the flexibility of mount, assuming spring and viscous coupling between payload and mount. A dual flexibility model on both payload and mount is also treated, and its theoretical transfer function is compared to the data obtained from a real stabilization system. Based on the results, measures to avoid instability in the presence of mount flexibility are proposed.

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In this paper, we study on the disturbance attenuation characteristic of the repetitive control systems. The repetitive control system has bad disturbance attenuation characteristics. For the certain frequency disturbance, conventional repetitive compensator amplifies twice as worse as the disturbance response of the system without using repetitive compensator. The multi-period compensator proposed by Goto et al. can attenuate the worst amplification degree rather than the conventional repetitive compensator. Effectiveness of the multi period repetitive compensator for the disturbance is not so sufficient good. To overcome this problem, we propose the design method of the repetitive control by using two degree of freedom structure called pseudo internal model control structure. Even if the plant has unstable zeroes, we can attenuate the disturbance efficiently small.

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This paper is concerned with the design of an active suspension system of 1/4 passenger Car models using the theory of sliding mode control. The model is described by nonlinear differential equations excited by an unknown input. The control for the active suspension is composed of LQ control and nonlinear switching control. The former is derived by using the linear control theory based on a reduced order linear model, and the latter is obtained by the stability condition of the sliding surface. The experimental results indicate that the proposed method is much improved in the suspension performance.

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Vibration control for flexible structures, such as flexible robot arms and flexible space structures, has been studied by many researchers. We proposed decentralized control for flexible structures by decoupling mode quantities of other linkS. But when modeling errors exist in the control system, the performance of the decoupling control goes down because the control method is based on the model. In order to consider of modeling error, the adaptive control based neural network is applied to the vibration control of flexible multi link system. By considering the axial forces in modeling, mode dynamics is given as nonlinear system. The effectiveness of the proposed control method is shown through simulations of 5 link robotic arm.

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The dynamics of an inverted pendulum system is generally described by nonlinear ordinary equations including trigonometric functions. Therefore, under certain conditions in the periodic motion of a cart, the pendulum exhibits chaotic motions. In this paper, we propose a new swing up control method for a parallel type double inverted pendulum using the chaotic motions that appear inherently in its dynamiCS. We calculate the bifurcation diagram in the control parameter plane, then design the swing up controllers based on this diagram. One chosen pendulum or two pendulums can be swung up from lowest position to upper positiom The experimental results demonstrate the effectiveness of this controller. We also compute the basins of attraction to understand the reason of effectiveness clearly.

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In this paper we present the first report of the liquid surface wave control of an incline-type automatic pouring machine, especially the model and control. We modeled incline-type pouring machine by a double pendulum system, the first pendulum is considered as a ladle and the second pendulum is as surface waves of liquid in it. First we considered reducing vibrations of the second pendulum by controlling the first pendulum angle. We calculate acceleration values that are product of the second pendulum velocity and constant values plus absolute its angles. After that, we make an aim angle of the ladle by adding an angle get from the previous acceleration values and a basic ladle angle. Controlling the ladle on the aim angle could reduce the second pendulum velocity. Second we simulated this system, and demonstrated a laboratory experiments.

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This paper is concerned with the sway control system for rotary cranes during swing operation. In the previous reports, sway control system in lever operation was performed by developing a sway angle sensor and a sway controller, and the load sway was regulated by a feedback control applying a regulator theory. However, a feedback control for a regulator theory needs an expert knowledge for a setup of parameterS. In this paper, a control system applied fuzzy theory that can setup parameters to each operator's taste has been proposed. It is confirmed by experimental results that the proposed sway system shows excellent performance and gives easy operation.

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This paper presents an estimation method for loss factors in Statistical Energy Analysis (SEA). SEA technique is applied to estimate the structure borne sound transmission in the middle and high frequency range, and the accuracy of SEA depends on the evaluation of factors required in SEA. Some evaluation methods for the factors have been proposed, but they require the complex analysis or the large amount of time for measurement and much knowbows. In this presented method, the power flow among subsystems in SEA is directly measured by the structural illtensity measurement, it needs no knowhows and a small scale of measurement. It is applied to make SEA models of some structures numerically and experimentally. As a result, it is confirmed that this proposed method gives the factors with high presicion for analysis.

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Bench test facilities that utilize rollers are broadly used in order to examine braking and other various performances of automobiles. In examinations using the bench test facilities that utilize rollers, measurement of tangential and normal line components of the force acting on the roller surface is very important but this is very difficult because the contact point of a tire and a roller fluctuates during the measurement. So far, examples of the measurement of these components of the force have not been reported. Therefore we considered a method for measuring the tangential and normal line components of the force continuously on the roller side under this fluctuation of the contact point. As a result, it became clear that the tangential and normal line components of the force could be obtained with a simple calculation if two orthogonal components of the force acting on the bearing mounts and the moment acting on the roller spindle were measured. Finally, we successfully made the apparatus on the basis of this method and it was shown that this apparatus had satisfactory characteristics. In this paper, we describe the structure and characteristics of this apparatus and show examples of measurement by it.

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Simulation and experimental studies are carried out for investigating the possibility of automatic vehicle control system based on absolute position information. Implementation of such control system requires a methodology of measuring the absolute position, and a control algorithm. An accurate and real time measurement of the absolute position by use of DGPS (Differential Global Positioning System) and sensors on a controlled vehicle is proposed. A steering control algorithm for tracking the desired course stored as absolute position data is also proposed. Simulation and experimental results validates the proposed measurement and control system, and provides the perspective of enhancing the automatic driving control system by use of the absolute position information.

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In this paper, we propose a decentralized control alogorithm for transporting a single object by two nonholonomic mobile robots. We extend the leader-follower type control algorithm, which we proposed for the holonomic robots⁽¹⁰⁾, to the nonholonomic mobile robots by introducing the dual caster action. The proposed control algorithm is experimentally applied to two nonholonomic mobile robots, and the experimental results illustrate the validity of the extended control algorithm.

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The immune network can provide a new technology suitable for dynamic problems dealing with unknown environments. We propose a new approach to behavior based AI using the biological immune mechanisms, We introduce the idiotope network which has been proposed by N. K. Jerne as the immune network system. The immune network system consists of the meodels of the immunity which is one of the information processing mechanisms in the living things. The basic principle of our proposed method is that the immune system selects the action which is suitable for current situation and the present immune network is handed over to the next generation. We apply the method to obstacles avoidance problems of mobile robots.

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The paper describes the development of an efficient suction mechanism for the floor cleaning autonomous mobile robot. Because available space and energy source, batteries, on the mobile robot is limited, it is not feasible to design a suction mechanism by simply providing a powerful actuator for sucking. We first discussed requirements of the suction mechanism for floor cleaning. Then we determined appropriate shape of the nozzle by simulating the flow of dust particles in the nozzle in the suction mechanism. The performance of the developd suction mechanism is demonstrated by comparing the experimental results of this mechanism mounted on the robot with the vacuum cleaner operated by human in an office building.

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The authors have proposed a marking robot which draws specific marks at designated positions on a ceiling board at construction siteS. After that, a new function was added to the robot. It is necessary to be work which draws a reference straight-line to a ceiling board in building construction sites. This report proposes about the method which makes this task do for a mobile robot. The system is composed of the standard laser, the prototype of Straight-line Drawing Unit (SLD Unit) which has a function of tracking the laser beam and a function of drawing, and the mobile robot. The robot loads the SLD Unit and moves toward the standard laser. In order to catch the standard laser beam, the robot changes its trajectory. The robot controls its two drive wheels in a way that allows each wheel to move independently, so it can trace a straight line. Based on the experiments, the robot could the task of drawing the amplitude of the straight line with an accuracy of plus or minus 1 mm when drawing a 10 m line. This paper mainly describes the SLD Unit and the wheel control, and presents the experimental results of marking by the robot.

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A design method of cooperative system consisting of multiple position controlled rotors is proposed. Passive joints are installed into each robot as mechanical compliance to avoid excessive inner forces caused by mutual positioning errors among robots. After the necessary kinematic constraints imposed on installed mechanical compliance for cooperation are derived, kinematic relationship between the infinitesimal displacements of robots and those of the handled object is obtained. Two cooperative systems consisting of three mobile robots are designed as cooperative mechanisms and their characteristics are analyzed. After showing that the maximum number of robots for cooperation is limited to six, a way to overcome this limitation is proposed using hierarchical structure of compliance mechanisms.

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In this paper, we propose a recognition method comparing characteristics of three dimensional CAD information with those of input images of several cameras. Several cameras are installed upper and lateral side of a recognition area to estimate three dimensional coordinates of vertexes which compose an object. Three vertexes of the object are determined in the input images taken by those cameras. Straight lines which go through the above mentioned vertexes are estimated, and three dimensional coordinates of vertexes (intersections) are calculated from those straight lines. Finally, the kind and direction of the object are determined by comparing the distance among vertexes and the normal vector of a plane made by three vertexes with those in DXF file of three-dimensional CAD figures.

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Reliability estimation of electric parts by using CCD camera and neural network is described. Breakdown of carbon film resistors in reliability test is estimated from image features by feedforward neural network. In general, degradation of electric device should be detected for constantaneous operation of every machines. Image processing techniques plays an important role in many engineering applications, developments and more efficient quality control. This paper describes some experimental results on reliability estimation using a neural network and image processing for reliability test. Performance degradation of carbon film resistor is estimated from their colour images. By using the sequence of images of the tested carbon filmed resistors, we attempt to find an appropriate estimated fault time for tested carbon film resistors, in order to establish a convinient method for reliability estimation. We first discuss some essential issues to be considered in reliability problems. It is shown that the image processing and neural network approach give a good results compared with real measured results. Furthermore, the efficiency of the method is indicated by applying to image data for calculation of mean time to failure.

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We aimed for permanently supplying the electrical energy to an apparatus for in vivo use such as a cardiac pacemaker and proposed a totally implantable electrostatic generator that harnesses the motion of a living body. The generating system consists of a battery for supplying electric charge, a variable capacitor for energy conversion, a capacitor of energy storage and two rectifiers. We made a honeycomb type variable capacitor whose capacitance is varied from 44 to 220 [nF]. It was possible to generate maximum electrical energy of about [μJ/cycle]. We found that the electrical energy for driving a cadinc pacemaker can be generated by using the honeycomb-type capacitor with higher capacitance.

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This paper deals with a phase plane analysis of motions of the C.G. (center of gravity) of the human body in the sit-to-stand movement. The motion is calculated by both the time history data of the three joint angles of ankle, knee and hip, which are measured by a positioning sensor, and human morphology such as mass and length of each part of the body. Experiments were done on four young healthy men. This analysis shows that the motion of the C. G. can be clearly recognized as three motion modes: acceleration mode and two convergent modes to an origin of the plane and to an equilibrium state of the standing state. Furthermore, the trajectory to the equilibrium state in the sit to-stand motion, which the elderly use usually, is a spiral, which is observed when the systern is close to an unstable state.

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In general, there is no good hardware of tactile curved surface display for tele-robot and virtual reality, because to present the curvature of the curved surface with continuous values is too difficult. On other hand, in the psychophysical studies, human visual and tactile sensations have illusory fusion characteristics. Namely, the human sensory quantity on size, position and orientation of object is different from the real quantity. Therefore, we can recognize curved surface of real objects through visual and tactile sensations, even if exact tactile information is not presented. Furthermore the visual information is realize easily by computer graphical technology. So, by utilizing human characteristics of sensory illusory fusion, realization of the tactile curved .surface display can be simplified. In this study, human fusion characteristics are measured by psychological experiments, and a tactile curved surface display is designed based on the results of the experiments. In the designed tactile display, only some curved patterns are utilized of instead of presenting many curved surface patterns. Namely, using the human sensory fusion characteristics on visual and tactile sensory fusion, the display of tactile curved surface is simplified.

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This paper discusses the interactive scientific visualization method which can represent the dynamic phenomena according to the user's action. The immersive multi-screen display CABIN and the parallel supercomputer IBM SP 2 were connected via the FDDI high-speed network to construct the interactive visualization environment. By using this system, two kinds of visualization methods, the realtime numerical simulation and the visualization using data set, were implemented. The calculation performance and the effectiveness of the interactive visualization methods were experimentally tested and evaluated. From these results, the interactive visualization is though to be very effective to understand the scientific numerical data intuitively.

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This paper deals with the problem of 2 D facility layout planning, in which each placement unit is a rectangular block having various shapes. In actual facility planning, a strong constraint might be added to a placement region. We cannot disregard the constraint. We propose some algorithms based on the evolution strategy (ES) and the genetic algorithm (GA) for the layout problem with the constraint. After tuning major parameters of the GA method and a family of the ES type algorithms, we compare the performances of these algorithms. Especially, we clarify effects of a multiple point mutation method and a new mutation method using normal random numbers on the ES type algorithms. Also, we propose a self tuning method of parameters for an ES type algorithm and show effectiveness of this method based on numerical experiments.

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Scheduling problem is one of the most important factors to facilitate effective manufacturing operation and rapid product development. De-centralized scheduling architecture with flexibility and robustness is required in manufacturing systems. This paper studies the abilities of evolutionary computation with multi-agent paradigm to move appropriately in relation to several process machines. Genetic algorithm is applied into the self-organization scheduling so as to improve the scheduling efficiency. Self-organized work flow is formulated with coordinated motions amongst autonomous work agents. The evolving work agents are capable of robustness and reliability coping with the several scheduling demands.

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This paper discusses the contact theories of the worm gears which have a cylindrical screw worm. First, known contact condition similar to that of spur gears is proved easily. Second, the known contact condition and author's contact condition similar to that of spur gears are synthesized and space image of normal is clarified. Third, the solution of the zone of contact and the opposite tooth surface of the worm gears are derived from the contact condition similar to that of spur gears. And solutions of contact condition which is shown by expressions is clarified. Finally, many examples of the zone of contact and the opposite tooth surface of the worm gears are shown and three dimensional expression is tried.

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Time-dependent behaviour in deflection on teeth of plastic gears was predicted. Based on the correspondence principle, viscoelastic solutions for tooth deflection and tooth root strain were obtained from the associated elastic solutions by replacing the elastic constants by the viscoelastic operators. To validate the viacoelastic solutions, we measured tooth deflection and tooth root strain on polyacetal and Nylon gears under cyclic load at frequencies of up to 30 Hz. Both tooth deflection and tooth root strain decreased with increasing loading cycle. Assuming that the viscoelastic behaviour of these plastics can be described by the three element standard linear solid, we predicted tooth deflection and tooth root strain. A good agreement was obtained between measured and calculated values of tooth deflection and tooth root strain.

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This paper proposes a simulator which can depict the rotational vibration of a spur gear having any types of tooth surface deviation including both tooth profile deviations and tooth helix deviations. The developed simulator is based on a single degree of freedom motion system constructed with equivalent mass, damping and mesh stiffness of a pair of gears. The mesh stiffness is calculated considering the effect of the tooth helix deviation which brings non uniform load distribution along the contact line of a tooth pair. The dynamic load tests have been performed to verify the simulator changing both helix slope deviation of driven gear and torque. The analytical results under each operating conditions are in good agreement with experimental results. Also, the damping ratio of the test gear system is evaluated as 0.03 with measured vibration responses, which is smaller than conventional expectation value of 0.07.

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In a previous paper, a method for cutting hypoid pinion was proposed. In the method, instead of a basic member which is a hypothetical gear conjugate to ring gear, a newly introduced quasi basic member is used as the actual tool gear to generate the pinion. The quasi basic member is an approximate gear of the basic member. This paper introduces the method for setting up the quasi-basic member on the hypoid gear generator, namely, the method for calculating the machine settingS. The calculation starts with the designation of a central point of tooth bearing on the ring gear tooth surface. The pinion tooth surface which is generated by the quasi basic member becomes approximately a conjugate surface, so that the transmission error of this gear pair is very small. The proposed method does not need the so called tooth bearing development. When the experimentally made pinion was engaged with the ring gear given previously, the tooth bearing was desirable one.

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It is well known that balls in a ball bearing are rotating three dimensionally. But it is not so easy to obtain this three dimensional ball motion experimentally. The only one method ever reported heretofore is the Hall element method developed by Kawakita et al., where some Hall elements are arranged around a magnetized ball so as to detect an orientation of a magnetic axis of the ball. Nevertheless the reported angular velocity has large fluctuation. This study was carried out to find out the cause of this fluctuation to increase the accuracy of the Hall element method. It starts from the derivation of some equations required to calculate the magnetic field around a uniformly magnetized ball. By means of these equations some possible factors are evaluated to cause fluctuation such as miss-alignment of the Hall elements, calculation method for angular velocity components and a slight deviation from the theoretical sinusoidal wave of the Hall voltage. The result shows all these factors have some responsible for fluctuation in angular velocity components especially the deviation from the theoretical curve has a large responsible for it.

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Cross-section roundness profile measurement is generally considered a significant procedure in the processing of parallel rollers requiring the highest quality in dimensional accuracy. This becomes a difficult procedure due to the fact that such rollers show extremely small dimensional error, resulting in expensive and time consuming measuring methods or, in most cases, the ignorance of the procedure itself. This report deals with the development of a roundness measurement system for high-precision parallel rollers based on a V-block double enlargement device. Experimental results which support the validity of the device have been reported in our previous paper, and here we focus on results obtained from the mass measurement of approximately 1200 rollers. Distribution of roundness and average radius are closely investigated to construct a practical method for the classification of dimensional accuracy of such parallel rollers. Furthermore, straightness measurement results of a high precision linear guide accompanying 400 parallel rollers selected with this method are presented to demonstrate the validity of such classification procedures.

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High operating speed of a linkage will result in the shaking force, the shaking moment and the driving torque to change greatly. Although either mass-redistribution or counter-weight method is utilized, the balanced effects sometimes are not satisfactory, furthermore it is cumbersome to search for the global optimum solution using the conventional nonlinear optimization approaches. This paper proposes a new mixed mass redistribution method. The optimum dynamic design using the new method is invastigated based upon the genetic algorithms. The results calculated by counter weight method and mass-redistribution one and the new one are compared, it is shown that the new method can more efficiently reduce the shaking force/moment than the other methods before, and driving torque than the counter-weight one. Moreover, it is also demonstrated that the genetic algorithms can obtain optimum dynamic characteristics more effectively than the traditional nonlinear optimization technique. Last, the small element method is used to form the shape of links according to the optimized linkage design parameters

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