This paper describes the coupling effects of horizontal and vertical seismic excitation on the response of a newly developed 3-dimensional base isolation system. This base isolation system achieved very low vertical natural frequency using a velocity reduction mechanism. Therefore, rocking motion will be induced by vertical excitaion as well as by horizontal excitation in the presence of mass eccentricity. And this sysytem employs sliding pads for horizontal isolation and friction dampers for vertical isolation. Thus, the vibrational response of the upper structure depends on the friction forces of the sliding and damping mechanism, and the horizontal friction force varies depending on the vertical seismic response, vice versa. In this study, the coupling effects of the horizontal and vertical seismic excitations are investigated analytically as for the rocking motion, response displacement and response acceleration. The effects of the phase difference between the horizontal and vertical seismic input, etc. are clarified.

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Mitigation of earthquake loads by seismic isolation technology is very promising for enhanced safety and economy of the next generation nuclear reactors. A research project has been undertaken for the development of 3D seismic isolation technology, under the sponsorship of the Ministry of Economy, Trade and Industry. There are two types of 3D seismic isolation system concept. One is the 3D entire building base isolation technology and another is the vertical isolation device for main component with horizontally entire building base isolation technology. For the former technology, three types of system concept were nominated. These are "Hydraulic 3D base isolation system", "Independent cable reinforced rolling-seal air spring" and "Rolling seal type air spring". This paper reports the performance requirements for 3D isolation system and the criteria for the system selection.

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In Japan, a number of three-dimensional base isolation systems have been studied, but these have impeding factors that are the difficulty of obtaining an adequate capacity on the vertical isolator for supporting an upper structure and for suppressing rocking motion. In this paper, we propose a new three-dimensional base isolation system that should solve the foregoing problems. This paper covers the results of the static and dynamic loading tests on scale models of the proposed system performed to verify expected system performance, and seismic response analysis reflecting the test results for commercialized FBR. The study was undertaken as part of an R&D project sponsored by the government for realizing a three-dimensional seismic isolation system applicable to future FBR.

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Three dimensional (3D) seismic isolation device has been developed to use for the heavy building like a nuclear reactor building. The developed 3D isolation device consists of the laminated rubber bearing as a horizontal isolation device and the rolling seal type air spring as the vertical isolation device in series. In this study, the four tests using 1/12-scaled models are carried out. The four tests are dynamic vertical and horizontal test, orifice-damping test, pressure resistant ability test, and accelerated aging test. As the results, the developed 3D seismic isolation device is confirmed to be applicable to a nuclear power plant.

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This paper shows the overview of the test results conducted to confirm the applicability of the proposed three-dimensional seismic isolation system to the actual advanced nuclear power plant. The tests consist of the shaking table test for the system and the integrity tests for the air spring. The integrity tests consist of the pressure test, the air permeability measurement test of the rubber sheet that composes the air spring, and the failure mode confirmation test. From those tests, it was understood that the proposed system could exhibit the seismic isolation function sufficiently, the air spring could resist the design pressure for 60 years in plant life, and the air spring has no catastrophic failure mode.

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A structural concept of a vertical component isolation system for new-type reactors, assuming a building adopting a horizontal base isolation system, has been studied. In this concept, a reactor vessel and major primary components are suspended from a large common deck supported by isolation devices consisting of large coned disk springs. The outline of the vertical component seismic isolation system and a series of model tests with full scale coned disk spring and damper are shown in this paper.

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Recently, the number of earthquake isolation structure has been increased. The most of earthquake isolation structure is applied the rubber bearings that are well-known as device. However, few light-weight structures such as wooden houses are not applied the isolation device, because it is difficult to apply the rubber bearings, for example, the diameter of the rubber bearing narrows according to extension of the natural period of isolation system, and the device can not support superstructure. In this study, the purpose is development about isolation system for Light-Weight Houses. we propose that the new isolation system is supported with the linear slider and force of restitution is given by transverse stiffness of the coil spring. In this paper, result of numerical analysis in this system was reported.

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The mid-story seismic isolated building has isolators at the mid-story and it is expected to apply for the seismic retrofit. The elevator for the mid-story seismic isolated building receives strong rail bending stress by the large deformation at the isolated story. A new elevator system has been established to reduce the rail stress. The system has a long rail fixing span at the isolated story. But it has complicated dynamic behavior such as large rail deformation and guide contact with the rail. To evaluate those dynamic response, we developed a nonlinear finite element model to evaluate the earthquake transient behavior and checked the rail bending stress. The simulation result was evaluated by the experiment.

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In order to achieve more perfect vibration-free environment in base-isolated semiconductor factories, a smart structure was tested for comprehensive active microvibration control in a base-isolated 2-story steel frame building model of a 5x3x4^H m external size and a 6,900 kg total mass which was supported by four multistage rubber bearings. In the building model, 20 piezoelectric actuators were attached to the columns and the beams, and four horizontal actuator units consisting of two piezoelectric actuators each and four vertical ones of the same type were installed between the bottom of the superstructure and the foundation. The controller was designed by a model-matching method. The tests showed that the smart structure could effectively control three-dimensional microvibrations generated in the building model and excited by external disturbances.

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This study has been examined the 3-dimensional measurement method for dynamic displacement of real scale test model on shake table tests. This system can measure 3-dimensional dynamic behavior of test model without any contact by applying an optical motion capture technique and image processing technique. The system therefore is the most suitable measurement system for an evaluation of complex 3-dimensional behavior of test model. This paper describes the dynamic measurement accuracy, the effectiveness of the proposed system from the results of shake table tests using the 2-story building model and the rigid body model.

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In this paper, we develop passive two-degree-of-freedom dynamic absorber and study the performance of this dynamic absorber experimentally. This dynamic absorber has two auxiliary masses, which are connected in series by springs and dampers. We design the parameters of dynamic absorber by using the method proposed by L.Zuo and others. By the vibration experiment, we know that this passive two-degree-of-freedom dynamic absorber is effective to suppress two vibration modes of structures.

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In this paper we verify availability of semi-active vibration isolation using a large-size magneto rheological fluid (MR) damper for a two-degree-of-freedom structure. We have already proposed the design method taking account of the mechanism of a fictitious damper model to obtain the gain-scheduled controller with linear matrix inequalities for semi-active system which is classified as bi-linear system. We confirm that the proposed method has good performance in comparison with passive damping systems and other controll methods by experiments and simulations.

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Semi-active seismic isolation systems using controllable friction dampers had been proposed to reduce response accelerations and displacements comparing with those of passive systems, although they had a problem that the dampers might fail to generate damping forces due to malfunctions in strong earthquakes. A new type of controllable friction damper with a fail-safe mechanism was developed to solve the problem in this study. For the damper, piezoelectric actuators were used to make the mechanism simple. The actuators are compact, and can make quick responses and produce large forces. Excitation tests were carried out for the semi-active system using the friction dampers, therefore the seismic isolation effects and the relative displacement reduction effects improved in comparison with the passive seismic isolation system.

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Smart structure, which are equipped with embedded (or bonded) actuators/sensors using piezoelectric ceramics, piezoelectric polymers, magnetostrictor, and so on, are proposed mainly for structural control of large space structures A smart structure with three different controllers were evaluated for vibration control of cantilever steel beam of a 150mm×6mm section, 1325mm height and a 23kg total weight. Piezoelectric actuators integrated to the beam were used for the vibration control by bending moment control of them. The controllers were designed using the Model matching control theory, the H^∞ control theory and the LQ control theory. The tests showed all three controllers could effectively reduce the vibration of the test model. Controller method of he Model matching control were considered prospective.

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In this paper, we consider a vibration isolation control problem in case of narrow-band frequency disturbances are applied to a system. The frequency shaping method by the H_∞ control is helpful for the problem, but can't be locate closed-loop poles in preferable region because poles of weighting functions of the generalized system become undetectable modes. In order to overcome this problem, we use extended H_∞ control combined with the robust stability-degree assignment method. By the method, we can design a controller that provides desirable frequency shaping and preferable closed-loop poles location at once. We conformed performance of the designed controller by experiment.

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The zero-power magnetic suspension system behaves as if it has negative stiffness. Suspension with similar property can be realized by using a linear actuator such as a voice coil motor. The controllers realizing negative stiffness with a linear actuator are compared with zero-power controllers analytically. The analyses show that they have similar structures. It is pointed out that a control technique, which was effective in widening the operation range of zero-power controllers, can be applied to the controllers realizing negative stiffness.

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This study deals with a fundamental research on non-contact control of vibration by utilizing acoustic radiation pressure. A control method of acoustic radiation pressure by modulating oscillating current directly is presented. In this report, non-contact vibration control experiment using electro-mechanically controlled system is carried out. Experimental system to confirm the capability of the presented method is built. The capability of non-contact active vibration control method is shown.

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This paper describes the vibration suppression of torsion systems of finite degrees-of-freedom (DOF) by using the wave absorbing control method with online computation of a virtual wave propagating system that is similar to the real system to be controlled. The vibration system is calculated online by Adams' method, and the controller which has the impedance matching characteristic is applied at the end of the virtual system. From the theoretical and expermental viewpoint, the characteristics of the control system are presented, and the validity of proposed method is demonstrated.

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In this paper treated is the impedance-matching wave absorption control of rope system near fixed end. The rope system is approximated by finite difference method and the end-element is controlled to absorb the vibration energy of rope system. The imaginary system in a controller that is constructed by the same elements as those of the controlled system with the impedance matching condition at the end is connected to the end element by the control force. The simulation has confirmed that the finite difference approximated system based control has enough effect to the distributed rope system. Also the results have verified by the experiment.

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This paper proposes cluster control for a flexible beam that enables the generation of the vibration-free state in the structure. First, the design procedure of the cluster control system is derived; clarifying the absolute stability of the system based on the displacement or velocity sensors. Next, cluster filtering method is presented which extract the four state variables (displacement, slope, bending moment and shear force) dominating the vibration phenomena. Furthermore, the characteristics of the control system are clarified by numerical simulation. Finally, the experiment on the realization of vibration-free state is conducted, demonstrating the validity of the proposed method.

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We have proposed a novel method to provide human tactile sensation using surface acoustic wave (SAW). A pulse modulated driving voltage excites temporal distribution of standing SAW. The distribution generates friction shift on the surface of a SAW substrate. When the surface with burst SAW is explored, the friction shift can be perceived as tactile sensation at mechanoreceptors in the finger skin. For real reproduction of tactile sensation, the burst frequency was controlled according to measured rubbing motion. We discussed the control parameters and their arrangement. Required parameters and their tuning for the tactile display were investigated.

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Time delay by image processing exists in the information acquired from a CCD camera. Since the renewal time of image information is longer than sampling time of control, control delay occurs and the following performance to a target trajectory is not good enough. In this paper, in order to compensate image information delay, we propose the method that combined Kalman filter, time delay compensation, and state estimation between sample points. Advantages of the proposed method are demonstrated by simulations and experiments in case all of relative joint angles are detectable from image processing data.

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SSM (Sensor Steering Mechanism) is constructed with the sensor arm and the deceleration gear system of which gear ratio is fixed to two to one. The existence of sensor arm prevents to realize SSM for conventional vehicles. This paper tries to replace the sensor arm with 1kHz Smart Camera which is developed recently. By using of the difference between left and right pixel values over the edge of side lines, the following control is applied to SSM-vehicle model. The experimental results show the stable cornering even if the rear part of the vehicle is drifting.

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This study aims at establishing an advanced visual feedback control method by extending the Cubic Neural Network (CNN) intelligent method. In this study, a qualitative controller was designed in consideration of the system characteristics, especially observational noise by using the genetic algorithm. This study deals with a problem of stabilizing a two-dimensional inverted pendulum by feedback control using stereo camera. To verify the noise tolerance of the proposed method, the computational simulations and experiments using a real apparatus were carried out. It was confirmed that the designed CNN controller had noise tolerance.

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This paper deals with sinus-lifting motion which is some animal snake motion such as raising part of body. This motion is known to be the effective action in dynamics and anatomy fields. Our approach in this paper is to analyzed this motion in the sense of control theory. A snake-like robot which consists of active joints and passive wheels with no side-slip condition is used in this paper. The concept of dynamic manipulability of a snake-like robot is applied to the general locomotion control for this model. Numerical simulations based on this manipulability show that sinus-lifting motion improve the manipulability and affect the period of body shape.

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In this study, we propose a grasp control system using compliance control. To avoid slippage of the grasped object, grasping force is increased by changing the joint stiffness based on the relation with the shear direction force, which is derived in the pilot study. Along with this brief standard, the additional joint stiffness is applied to always bind the force vector endpoint in the appointed region of the friction cone where the generating force is thought to be optimum. The proposed control system, containing this variable stiffness matrix, is actually applied to the multifingered hand, and its practicability is verified.

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At present, applications of robot technology in medical treatment and nursing care field are required. Their robots are demanded environmental adaptation. The wiping operation, which aim at this paper, is important to accustom to external environment. Then, we propose the method which improve contact force for reference force by means of comparing measured value by force sensor with friction force and taking them into consideration. We used the sliding mode control as a position controller. As a result of applying this method to the manipulator, it was verified the usefulness of the proposed method.

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This paper deals with the non-contact transportation of target specimen using the ultrasonic wave. It is the purpose of this paper to examine a possibility of rotation and position control using traveling wave control technique, and to anayize squeeze film due to the traveling wave. Firstly from the view point of a numerical analysis, the principle of transportation is presented by the pressure distribution of a squeeze film. Next, experiment of the transportation and the positioning control using the method of traveling wave of the beam controlling the phase are carried out. Finally, experiment of rotation control of levitated object in the transportation using the same method of the above proposal are accomplished, and the accuracy of these method is investigated.

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In this paper, we propose a method of autonomous autorotation landing control by small unmanned helicopter. Autorotation is a flight method of getting energy from air and obtaining a thrust by falling, and if this is automatable, when abnormalities occur in engine, it will become possible to land safely. As a summary, we identify the linear model from experimental data and blade elemental theory, and apply optimal tracking control to the model. And we verified the validity of the method by performing experiment and simulation.

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As a new control technique, rule-based pseudo sliding-mode control system is developed. In the rule based pseudo sliding-mode control system, the transient solution is constrained on the subspace that is spanned by the corresponding eigenvectors with negative eigenvalues of the linearized system, and consequently, the similar motion to the sliding-mode is generated. In the previous report, we demonstrated theoretically and numerically the fundamental feature of the rule based pseudo sliding-mode control system, such as prevention of chattering and high robustness. In this report, the validity of the present control technique is confirmed by comparing the results of the experiment with those of the numerical simulation.

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The vibration analyses in which the head of the wheels is harmonically excited in radial direction were carried out by using FEM for the wheels of Straight web. TGV-type web and Wavy web with four kinds of circumferential wave number, and then by taking those vibration responses as boundary conditions the acoustic analyses using BEM were conducted to obtain the acoustic radiation power. And by random vibration analyses considering the rail surface roughness, the mean square velocities of rail at the contact point between rail and wheel were calculated. From the above results, the sound radiation powers of various-type wheels were examined in order to clarify the influence of wheel configurations upon the rolling noise of the railway wheel / rail system and to get the fundamental knowledge towards the optimal design of the configurations of the wheels with wavy web.

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In this paper, the authors propose a new method for optimum design of bending grooves on vibrating panel-like structures to reduce noise. It is proposed in the method to use the mapping of sound pressure level on the panel's surface for best positioning of a groove and to apply the particle swarm optimization algorithm for determining the best dimensions of the groove. Then, an experiment is carried for a panel having a optimum designed bending groove to verify the varidity. It leads that the grooves designed by the optimization method can realize good reduction of sound power.

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For the purpose of enhancing the control effect of a conventional Helmholtz resonator for absorbing incident sound in a wide frequency range, this paper presents a newly developed Helmholtz-based resonator. The principle of the resonator presented in the work is relied upon the frequency property of a flexible panel installed in a resonator cavity, thereby enabling to broaden the effective frequency range of the sound absorption. The resonance frequency of the panel is designed to tune to that of the resonator, so that the resonant peak is split into two. An absorption coefficient as well as acoustic impedance density of the resonator is derived analytically. Then, from a viewpoint of a numerical simulation, fundamental characteristics of the resonator system with those parameters are investigated. Finally, an experiment is conducted, demonstrating the validity of the proposed resonator.

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It was found that vibration amplitude at any position of a structure with vibration absorbers can be calculated analytically by using the specification of absorbers and mobility of the structure evaluated by experiments or numerical calculation. The calculation of the sound power generated from a simply supported beam with the absorber leads to the following results. 1) The absorber set at exciting point has a highest ability of the sound reduction. 2) A bending rigidity plays an important role in the sound reduction when the position of the absorber is different from the exciting point.

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Door closing sound of a car is one of the important things as a factor which affects the quality of vehicles greatly and raises the charm of a car. Therefore, it has been studied for many years. In this paper, it is characterized by narrowing down the factor expressing door closing sound by using the Semantic Differential Technique and factor analysis. Furthermore, equations which can presume the psychological quality of door closing sound with the objective parameters are drawn by multiple linear regression analysis. Moreover, it is shown by relating the factor to the hedonic scale of test subjects that door closing sound for which the user is asking can be expressed in two-dimensional sound quality space by using the pair comparison method.

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The purpose of the present investigation is to develop a small-sized bone conduction speaker by using piezoelectric vibrator. At first, The bone conduction speaker is constructed with the piezoelectric vibrator connected by rod, and rubber-weight which improve the vibration characteristics. In the experiment, the evaluations of voice articulation under masking-noise are carried out in order to examine the effectiveness of voice recognition. The experimental results show that the evaluation words could well be recognized under masking-noise, and the voice articulations are improved by using rubber-weight. In addition, the voice articulation is more improved when the bone conduction speaker is fitted in auricular cartilage.

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In this research, an acoustic diagnosis technique correspond to strong non stationary signal for a failure rolling bearing a kind of rotary machinery components is proposed using adaptive signal processing algorithms. This proposed acoustic diagnosis technique is used to three adaptive signal processing algorithms to identify optimum algorithm for exactly detecting failure rolling bearing. In this paper, applied adaptive signal processing algorithms are investigated against adaptive line enhancer a kind of adaptive filter to extract a periodic abnormal signal including noise generated by machinery components. Finally, optimum adaptive algorithm in order to diagnose a failure rolling bearing has been identified using a rotary machinery simulator.

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The purpose of this study is to make clear that the shape of structure influence on vibration energy. The vibration energy flow is expressed by vibration intensity (VI). In this paper, we use a beam with suddenly changed cross-section. The beam is analyzed by finite element method (FEM). The vibration intensity is analyzed by finite difference method (FDM). Then, we investigate that the suddenly changed cross-section of beam influence on the vibration intensity. As a result, it is clarified that the vibration intensity is one of the effective parameter to estimate the thickness of the beam.

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Braces on Soundboard of acoustic guitar have an influence on sound quality. Usually, the bracing location depends on guitar maker skill and feeling. There are no guidelines for designing bracing pattern. This paper describes a simulation results for the full-scale soundboard model of an acoustic guitar. From the simulation results, brace spacing have largely an influence on the vibrating surface area size and the radiation power from the soundboard. And, the soundboard with new bracing pattern is proposed and discussed numerically.

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Cluster control enables a target cluster to suppress without causing spillover into any other cluster. Active cluster control of vibration is useful in suppressing of the total acoustic power. This paper presents active control of sound transmission of a rectangular plate using structural modal cluster control(Active cluster control of sound transmission). The experiment is conducted, demonstrating the validity of the cluster control for suppressing the penetration of acoustic power.

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This paper deals with generation of virtual sound image in qwiet field which is the combination idea of virtual sound image and active noise control. Optimal control law which minimizes total of the square of the sound pressure in arbitrary domains is derived. Numerical simulation is carried out, demonstrating the control effect for minimizing total of the square of the sound pressure. The validity and the problem of the optimal control law which was derived were clarified.

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Active noise control of a moving point has been examined in our previous papers. The feature of the model is that the transfer characteristics between the noise control source and the evaluation point (aimed noise reduction point) change with the movement of the evaluation point. However, the convergent algorithm used in the identification works effectively only when the system is stationary, and this is one of the reasons that the identification accuracy decreases with the increase of speed of the evaluation point. We propose new technique where transfer characteristics are divided into time delay factor and main components. The change of transfer characteristics caused by the movement appears mostly in time delay factor, and since it is the function of the location, there is no need to identify it. This method is examined numerically and experimentally in this paper.

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In active noise control (ANC), the transfer function of the error path (TFEP) changes when the evaluation point moves, and it causes a bad performance of noise control. In this study, a new method to identify TFEP at an arbitrary point is proposed. This method is based on the plane wave theory, and impulse response of TFEP is derived analytically as a function of the position, using measured impulse responses at two points. Applying this method to update the compensation filter of the varying TFEP by movement of the evaluation point, it is verified by the experiment that the noise can be suppressed.

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This paper concerns the minimization of acoustic potential energy in a strongly coupled acoustic/stuructural enclosure using both active noise control (ANC) and active vibration control (AVC). A target enclosure is composed of rigid walls and flexible panels that are subject to external forces. Optimal feedforward control law to minimize the acoustic potential energy situated at arbitrary locations. Then, Numerical simulation is carried out, demonstration the control effect for minimizing acoustic potential energy using ANC and AVC.

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Periodic noise radiated from two dimensional space between two square plates is controlled by active noise control. Noise source is put at center of the space and a control speaker is set at the same location. Filtered-X adaptive notch filter is used and the control system consists of the speaker and a microphone for control error detection. The noise source is sine wave sound or triangular wave sound and a period of the noise is known in the control. It is shown that the sufficient noise reduction is achieved for the controlled frequency component as well as in circumference of the square plates.

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This paper deals with the experimental result of the polygonal deformation phenomena in contact rotating system. The experimental device on the model of hot leveler of the steel making machine was manufactured, and the polygonal deformation was generated in the upper roll. The experimental result was compared with analysis, and the countermeasure by changing operating speed was examined.

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