This paper presents a design procedure of H_∞ controller for bending-torsional coupled vibration of flexible robot arm. In the case that the arm does not hold the center of the payload, it processes bending-torsional coupled vibration. In this research, H_∞ robust control design with structured uncertainties is utilized to describe the uncertainty in coupling of bending-torsional vibration. Moreover, this research designs H_∞robust control without structured uncertainties and compares the control performance of H_∞ robust control design with structured uncertainties and without structured uncertainties. In this research, an experimental system is set up and its physical model is made by utilizing the modeling method presented by Seto. According to this result, controller design method is certificated.

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This paper deals with transversal motion and vibration control for a flexible tower-like transportation system taking account of elevator to lift payloads vertically. Applying a lumped modeling method presented by Seto and LQI-based control system, the controller which achieve good performance are designed. As well, this research investigates problems which may occur in actual transportation systems through simulation using the vibration analysis software, MATLAB. The purpose of this research is to control motion and vibration under moving flexible transportation systems. It is demonstrated that this transportation system moves without vibration from one side to another at a high speed, and that the multimode-vibration of the flexible structure are controlled without spillover caused by neglected higher modes.

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In the contact work using the vision sensor, the contact itself is not realized when the distance to a subject estimates short. On the other hand, when the distance to an object estimates for a long time, there is a possibility that excessive shock power may occur, at the time of contact. Therefore, high accuracy is required of the position information acquired from a vision sensor. In this research, we built the vision servo system, which used active vision system, and realized highly precise position control by proposing the off-line calibration method. Moreover, the contact work by the system was done and the usefulness of this technique was proved.

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In this paper, we propose the grasping control system based on position control. In research of a multifingered hand, the problem is the slip produced between the fingertips and an object. Then, the friction coefficient between the fingertips and an object is identified in real time, and we propose the grasping control system to which the stiffness of the joint is changed based on the value. The friction coefficient is computed using the forces of acting perpendicularly to an object and those of acting in shear direction. Since this control system is based on position control, it is not necessary to switch a control system by approach and grasp. Therefore, this control system is stable. The proposed control system is actually applied to a 3-fingerd hand, and the usefulness was verified.

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The mine detection hexapod robot COMET-III is driven by hydraulic power. Because of the strong nonlinear characteristic of the oil pressure system, conventional classic methods produce the flattery delay to the target orbit. In the unknown environment of minefield, the robot leg must follow correctly the walking orbit. The sliding mode control has strong robustness to parameter change or disturbance, and the preview control prevents the flattery delay by using a future target value. In this paper, we design a preview sliding mode controller, which incorporate the advantages of both control theory, and so improves control performance.

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This paper is concerned with realizing universal walking on regular ground by robot as a spider. First, walking of a spider was observed and then, its pattern was examined. Secondly, the walking motion of a spider robot with 8-legs was implemented experimentally, and then it walked on the floor actually. It was confirmed that it could walk to the advance, the revolution and so on. Also, the usefulness of 8-legged walking was shown through evaluation of stability margin. Finally, as the first step to a walk of a creatural spider, the simulation of the velocity control for walking which was adaptive for the environment was tested for fatigue, fear and so on by using the neural network.

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This paper investigates the characteristics of a mobile mechanism that consists of a main mass, a foot mass and a slant leg. A rotational spring is attached at the joint of the upper end of the slant leg and the main mass. The lower end of the leg and the foot mass are pin jointed. Besides, the mechanism is equipped with a voice coil motor between the main and foot masses. When the exciting force is given by the voice coil motor, the mechanism travels due to the difference in friction force between forward and backward direction between the foot mass and the floor. Numerical simulation and experiment show that the moving direction and velocity are controlled by the frequency and the wave shape of the exciting force.

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This paper deals with a snake like mobile robot. Since animal snakes have many joints in their backbone, they can be regarded as continuum. Similarly, we assume a continuum snake model obtained as a limit with infinite number of joints. According to the continuum model, we derive 1) kinematics and dynamics, 2) optimal distribution of bending moment, 3) manipulability based on constraint force.

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Mechanism of damping is studied in this paper form the both viewpoints of micro and macro. First, it is explained how viscosity originates in the potential energy field caused by van der Waals gravity and electronic exchange rejection force among atoms and molecules. Second, it is described how viscous damping force proportional to velocity is caused by shear displacement between atomic rows accompanying material rearrangement. Third, role of viscosity in the free vibration is related. Forth, it is explained how amplitude increases infinitely in the resonance of forced vibration of undamped system. Fifth, the process is shown by which damping makes the resonance stable in forced vibration, and its mathematical expression is given.

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Damping mechanism of polymer material is introduced in this paper easily to understand for mechanical engineers. First, dynamical characteristics common to polymer materials are related. Second, mechanism of joint combination is presented which causes these characteristics. Third, physical properties of polymer in glass region and in rubber region are introduced. Forth, the reason why polymer reveals exceedingly high damping effectives is explained. Fifth, notice points for successive application of damping material to machines for decrease of their vibration are given.

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This paper presents the results of an experimental and analytical study of the performance of particle dampers using some cavities. This damping is a form of impact damping in which particles collides with the cylindrical surface of the cavities. The dynamics of the damper is solved by Discrete Element Method (DEM). The validity of the numerical method is examined by comparison with experimental results. The effect of some of the major system parameters such as the cavity number, container dimensions and mass ratio on the damping studied.

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Active Vibration Control is introduced to a regenerative vibration damper. It is intended to improve vibration reduction capability using the regenerated energy. An electro-dynamic actuator operates as an energy regenerative damper and an active control actuator. This requires a switching control algorithm. A simple experiment is performed and the results show possibility of the proposed system.

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In this paper, the authors propose a new type of hybrid magnetic damper using a lever-type displacement magnifying mechanism, which gives damping within a relative displacement in the region of about 0.1∿10mm. The trial damper was made and the resisting force characteristics were measured. The frequency responses and seismic responses of a three-dimensional piping system supported by the damper were measured using an electrohydraulic type shaking table. The experimental results are compared with the calculated results obtained by the FEM software (ANSYS), and the effects of vibration suppression of the hybrid damper are discussed.

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In this paper, a two dimensional isolation table using semicircular arc springs and a magnetic damper which has a simple construction, low height and the capability of vibration isolation in the horizontal direction, is proposed. The trial isolation table was made, and the seismic and frequency responses of the table installed a mass were measured using an electrohydraulic-type shaking table. The experimental results were compared with the calculated results, and the effects of vibration suppression of the table were discussed.

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In most cases, the conventional method (called center exciting method) has used for evaluation of damping steel sheets of constrained type. However, it has come to our attention that the method has often resulted in a high damping factor. Investing a new evaluation method for vibration damping property of steel sheets, work was carried out to measure a free vibration in attenuating generated to oscillate a resonance frequency to a test peace and then, calculate damping factor for it with the measurement result by a theological formula. Indication was made that the damping factors obtained by this scheme was always lower than those calculated based on a transfer function by the conventional method. As a conclusion, it was realized that a considerable margin of error affected the difference between the results given by the evaluation methods. The new method we tried assures stable attenuation vibration from the first mode to a higher mode; thus securing more accurate calculation of the damping factor.

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This paper proposes a design of simply supported type dynamic absorber for spindle. The dynamic absorber is designed from the view of feedback control with restriction for fatigue of the rod of the dynamic absorber. The design problem is formulated as a decentralized H_∞ static output feedback problem in state space. The controller is obtained by solving Bilinear-Matrix-Inequality (BMI) problem. In according to the design method, we design the proposed dynamic absorber and confirm the usefulness of the design method by the simulation.

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This paper is concerned with a design method f multi-degree-of-freedom dynamic absorbers which can suppress multiple vibration modes passively. Design parameters of the dynamic absorber are determined by utilizing the theory of the H∞ static output feedback control theories and by solving Bilinear-Matrix-Inequality (BMI) problem. Finally, numerical simulations for the two-DOF dynamic absorber show the advantages of the proposed design compared with the conventional SDOF dynamic absorbers.

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Shape memory alloys have origin-oriented hysteretic restoring force and their restoring force has the characteristic that restoring force doesn't keep increasing as deformation becomes larger. Using this characteristic to base isolation device, it can restrict the transmission of acceleration from the source of vibration. In this paper, the spring using shape memory alloy wires are developed and the base isolation device using them is developed. We investigated its base isolation effect and its durability. We find that the base isolation device using shape memory alloy wire can restrict the transmission of acceleration from the source of vibration and the performance of the spring using shape memory alloy wires don't change till it breaks.

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The multiplication of Dynamic Vibration Absorbers (DVAs) has been studied for several years to improve is performance. However, the optimal regulation of DVA becomes practically difficult for increasing of number of DVAs. In the paper, multi-series-mass DVA has been studied to improve vibration control performance and regulation easily. The optimal parameters of two-series-mass DVA and three-series-mass DVA have been calculated for compliance optimization, so that optimal design diagrams shall be conducted. The performance of vibration control is analyzed through the simulation and experiment. The results show that the two-series-mass DVA improves its performance, in the same ratio, by about 20% than the one-mass DVA, by about 11% than the two-parallel-mass DVA; while the three-series-mass DVA improves its performance, in the same total mass ratio, by about 25% than the one-mass DVA, by about 11% than the three-parallel-mass DVA; and both they show better results than the four-parallel-mass DVA.

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Floor impact sound in condominiums has been the important problem to live in comfort. Especially heavy impact sound caused by children's jumping on the floor is a serious problem because there is no effective devices to reduce that noise. In this study, a momentum exchanging damper was presented to reduce the impulsive vibration of the floor. This damper was composed of a spring, a dashpot and a mass which is adjacent to the floor surface. When a heavy impact source falls on the floor, the momentum of that source is transmitted to the damper through the floor, so the displacement of the floor could be reduced. Simulations and experiments were achieved to verify the effectiveness of the damper. It can be concluded that the damper significantly decreases the impulsive displacement of the floor and the impulsive force transmitted to slab from the floor.

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Abstract-Active and passive mass damper have different performance for vibration structure. Active mass damper has good performance for vibration control systems against winds and small earthquakes. On the contrary, Passive mass damper is efective against big earthquakes. In this paper, we propose some switching vibration control method; switching between passive and active. The vibration control device is pendulum type mass damper with an active mass damper on the end of the pendulum, which works as a passive mass damper without control input and as an active mass damper with control input. Numelical simulations and expelimental resuls show that the proposed switching vibration control has better performance than full time passive and active mass damper.

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By special designing of magnetic gaps, made by two pole pieces of a ring-shaped magnet and an inner magnetic yoke, the authors could make a very simple and cheap magnetic damper effective for three axes. The two magnetic gaps have conical shapes which are effective not only for radial two axes vibration but also for axial one. The magnetic attractive forces in the gaps counteracted by sandwiched gum sheets. The effectiveness is shown by several experiments. A very simple mathematical model which explains damping force due to a.c. leakage magnetic flux was proposed.

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At present there are no control devices that can be matched for both small and large earthquake of a high-rise building. In order to control vibration of such a building, the connected building control method and variable damping device for realizing the semi-active control system is used. The semi-active device is defined as a kind of passive device with variable properties changed by external maneuvers. A magnetorheological fluid damper as a variable damping device is used. This paper presents two methods for designing the semi active controller with Genetic Algorithm and LQ control theory. The simulation and experimental results demonstrate the availability and possibility of semi-active control.

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This paper presents an active isolation system with a lightweight table and multi modes of vibration. Then the lightweight isolation table becomes more flexible, causing the appearance of elastic multiple modes. Therefore, a control system should be designed which takes into account multiple modes. In this paper, the reduced order physical model proposed by Seto is used for designing controller an active isolation system with an elastic table and multi modes of vibration. For controlled system design, LQ control theory and double-active control method with feed-forward control are applied. Moreover, the effectiveness of the method is demonstrated through simulation and experiment. And, the effectiveness of the system with LQ control theory is verified through simulation when an addition structure is installed in lightweight isolation table.

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This paper presents a new method for the motion and vibration control of a three-dimensional flexible shaking table. The shaking table needs to be lightweight in order to be able to exactly reproduce earthquake waves and a variety of input signals. However, elastic modes then appear on the shaking table while operated in the frequency region. It is therefore important to simultaneously control the motion and vibration of the shaking table. The purpose of the research is to control the vibration and motion of a shaking table using the reduced order modeling technique and LQ and LQI control theory. The modeling procedure and control design are described. Control simulations on the discrete model are carried out to demonstrate the effectiveness of the method. Experimental work is presented in order to demonstrate a final verification.

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The National Research Institute for Earth Science and Disaster Prevention (NIED) is now conducting for constructing a three-demensional full scale earthquake testing facility (E-defense). The shaking table in this facility will be equiped basic controller designed by Three Variable Control (TVC) Technique. However the procedure todeterm the control gain has been entrusted to the experience of the person who adjusts the gain. Therefore the procedure has not been clarified. To equip a more highly developed control, we should understand the performance of the TVC. This study shows the design technique of TVC and FVC by mathematical process.

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Considering lessons from the recent earthquake disasters, NIED is now constructing the three-dimensional full scale earthquake testing facility (E-defence). To develop a new operation and control method for the shaking table, the Minimal Control Synthesis (MCS) algorithm, which is one of the model reference adaptive control (MRAC) methods, was applied to the system of shaking table-test model. We have proposed an operation and control method for small and medium sized shaking tables and the method have been implemented. The efficacy of the MCS method has been proved by the experiments. This paper reports the results of the experimental studies.

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The 3-D Full-Scale Earthquake Testing Facility (E-Defense) is now under construction in Miki City near Kobe. The test model considered for this facility has a mass of 1200 tons compared to the shaking table mass of 750 tons, i.e., 1.6 times as heavy as the shaking table. For this reason, it is considered that the reaction force from the test model to the shaking table is considerably large, and this degrades vibration re-creation performance of E-Defence. In this study, first, the analytical model that expresses coupled dynamics of the shaking table and the test model is derived based on experimental data which is obtained by using the middle class shaking table. Then, parameter study is conducted in various situation using the analytical model, and finally the control design problem of this kind of coupled system is discussed.

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In Japan, it is important to consider the structural seismic safety in architectural and civil structures, because a lot of earthquake breaks out. It must also be examined the mechanism and the structure which can expect to reduce the structural responses. The research and development of the base isolation system for the light-weight house has been carried out in recent years, although the isolation system has been applied for comparatively large structure such as office building and condominiums until now. In this study, the new base isolation system for the light weight house using friction and rubber bearing. This paper describes the basic concept and the efficiency of proposed system from a seismic response analysis.

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In recent years, the number of earthquake isolation structure has been increased. The most of earthquake isolation structure is applied the rubber bearings. However, rubber bearing is not fit to use for light-weight structure such as wooden house. Because natural periods depend mass of superstructure. Therefore the diameter of the rubber bearing narrows according to reduction of the mass, and effective area of rubber bearing becomes small according to changing rubber shape. And then the device can not support superstructure. In this study, we propose new isolation system for light-weight house using rubber bearing and friction mechanics. This paper describes result of numerical analysis in this system.

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Microvibration control technology has been rapidly becoming more important in a number of fields including superfine technology in semiconductor manufacturing and microgravity research experiments in space. In the paper, we propose the system which carries out vibration control of concrete foundation by using the piezoelectric actuator, to improve isolation performance. However, there were very few studies focused on the vibration control of concrete foundation in the past. We expect that it is difficult to realize the system in a nonlinear characteristic. In this study, the realization possibility of the proposed system is verified through the vibration isolation experiment using the scale-down model of the concrete foundation. In addition, a model matching controller is used as the control function.

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In recent years, research and development of various types of dampers were applied to several structures, such as buildings and large-scale industrial structures, in order to reduce their seismic responses during earthquakes. An elastomeric extrusion damper having its simple configuration was proposed as a large-capacity damper. The damper used un-valcanized rubber as its working fluid, and could obtain large damping forces by throttling plastic flow of rubber in a vessel. In this paper, dynamic tests were carried out for a full-size damper, which was designed to have a 500kN damping force at velocity input of 0.25m/s and could be used for vibration control of high-rise buildings and large-scale industrial facilities. From the experimental results, the load-displacement characteristic of the damper was found to have a rectangular shape with the rounded corners, and it was also confirmed that the damping force was proportional to the velocity raised to the power of 0.1107.

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A compact horizontal seismic isolation device with lowers natural frequency and long stroke is developed in which a roller with two spherical surfaces that have different radius and centers is used to produce the restoring force when the roller swings. This paper introduces the characteristics of isolation device, analyzes the natural frequency and investigates the relationship between roller's parameters. With the analysis and experiment, it is found that the natural frequency of the isolation system with the developed isolation device is not affected by loaded mass.

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The main objective of this research is to develop the vibration control systems for large span structures using spatially dispersed arranged TMDs (tuned mass dampers). When applying this method, we should consider the arrangements and design parameters of plural TMDs by different method using the usual single TMD. First, focusing on the issue of set-up of design parameters, the effects of the systems using single TMD and two existing methods of MTMD (multiple TMD) are analytically compared by using an arch model. The results show that the determination of the bandwidth of MTMD is very important. Next, we propose the arranging method of plural TMDs using MTMD and compare the proposed method with generally used method using single TMD.

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When independent type acceleration sensors with communication networks for instantaneous information transmissions are ready to use, structures can correspond to future agitations beforehand. The pseudo feed-forward type control becomes possible for various agitations. As a result, it can be expected that response of controlled structures reduces for unknown agitations such as various earthquakes. In this report, earthquake response analysis is carried out for an isolated wooden house with pseudo fee-forward controlled variable stiffness device to let a period of structure change under the concept of anti-resonance. Analysis results show that earthquake responses of acceleration and displacement in case of controlled structure decrease from those of not-controlled structure.

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The semi-active oil damper described in this paper switches is damping coefficient from maximum to minimum and dissipates twice as much energy as an ordinary passive damper. Its performance has been already verified under both dynamic loading tests with the full-scale device and the forced vibration test on the mid-rise building which was the first building with this semi-active oil damper. In order to verify the performance of this semi-active oil damper under low frequency and small vibration, forced vibration test was conducted on a high-rise building whose first natural period is over 4sec. The results showed that the damper added a lot of damping even at a very small stroke, about 0.1mm.

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Many vibration monitoring methods including remote monitoring are proposed for structural diagnostics or damage identification. And vibration control has been studied in order to maintain or improve structural performance. It is expected that the combination of remote vibration monitoring and vibration control have possibility to establish reasonable structural maintenance system. A low-cost remote displacement measuring system using PC camera and TCP/IP network is developed in this study. Property of the measuring system is examined in vibration measurement test. Moreover, semi-active vibration control experiments are performed on steel tower model by using proposed displacement system. From results of experiments, the remote vibration measuring system has basic applicability as sensor system of semi-active vibration control on tower structures.

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In this paper, using the concept of the equivalent external force, we develop a linear algorithm to identify dynamic parameters of structural system. An identification algorithm is also developed for the case that the measurements of the structural responses are limited at several floors. In proposed identification algorithm, we first estimate the equivalent external force at unobserved portions of structural system, and then identify dynamic parameters of structural system using the recursive least-square method. The efficiency of our proposed algorithm is verified through two numerical examples.

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Full-scale measurement is conducted at major bridges of the Honshu-Shikoku Bridges including the Akashi-Kaikyo Bridge. Of its purposes, bridge monitoring at extreme events such as strong wind and verifying wind-resistant design is the most important. In addition, vibration test, which was carried out on several long-span bridges in Japan, was not carried out on the Akashi-Kaikyo Bridge. Therefore confirming vibration characteristics will be precious in terms of securing safety to flutter. Ambient vibration data was obtained on the Akashi-Kaikyo Bridge and analyzed this time. Modal parameters of the bridge were identified. Particularly, modal damping was first identified for the Akashi-Kaikyo Bridge.

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A measurement system to accurately capture the 3D dynamic behaviors of membranes is constructed with the aid of the image processing techniques. At first, a hardware system for the image processing and the experimental setup are briefly described. Then, an image processing technique to trace the 3D dynamic behaviors of the membrane is developed. This method employs the 3D rotation, 2D isotropic expansion and 2D translation in the stereo matching, in which the corresponding points in the three stereo images are effectively searched by the derivative-free optimization strategy. Finally, the 3D deformation field of the membrane is recovered on the basis of the epipolar geometry. The 3D Deformation field is found to well reproduce the real behaviors of the membrane. In addition, they agree well with the measurement result of the laser displacement meter, which indicates that the developed method is also accurate quantitatively.

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A new fiber-optic vibration sensor has been developed and applied to structural health monitoring. The sensor is based on a new finding that frequency of light wave transmitted through a bended optical fiber is shifted by vibration at the bended region. The durable, low-cost and high-sensitive sensor can be used as multi-point AE/vibration sensing system. The new fiver-optic sensing system was applied to health monitoring of a full scale model of a reinforced concrete infrastructure. A method of AE location detection is also proposed based on frequency distribution of AE waveform.

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Damage detection in a structure from changes in global dynamic parameters has received considerable attention in the past few years from the civil, aerospace, and mechanical engineering communities. The basis for this approach is that changes in the structure's physical properties (i.e. boundary conditions, stiffness, mass, and damping) will, in turn, alter the dynamic characteristics of the structure, such as, resonant frequencies, modal damping and mode shapes. In this paper four different damage identification methods, based on changes on mode shapes and resonant frequencies, are applied and compared to detect and locate different damage types using experimental and numerical data extracted from simple steel beam. Some improvement has been introduced to these methods in order to increase the accuracy of localizing the damage position.

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Seismic damage is significant for civil structures like bridges, highways, gas pipelines, water pipe lines and sewerage pipelines. Sewerage pipeline breakage is reported in some erthquaque. It is important to know fracture of the sewerage pipelines after the earthquakes even though the recover of the sewerage pipelines are not emergent. To know the damage, a low-cost structural-health-monitoring system is required. In the present study, a new distributed fracture sensor is developed using glass comp9osites and a tiny embeddable in glass composite structures. The new fracture sensor is made from glass composites and carbon black composites. In one of the surface layers, the glass fiber is cut to make a crack starter. When large deformation is loaded, a crack start to grow, and the crack breaks electric conductance of the carbon black layer embedded in the glass composites. This causes electric voltage change, and the change is monitored through the Internet. Several experiments are performed to confirm the effectiveness of this system here. As a result, this system successfully provided the fracture information through the Internet

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Recently, long-lived active use of infrastructures has become a very important problem in all over the world. The damage identification of infrastructures is the effective technique for the maintenance and rehabilitation of bridges, tunnels and so on. The purpose of this study is to propose a sound monitoring system for bridges and investigate damage identification method by using sound monitoring data. The sound monitoring damage identification system in this study is constructed by using digital audio interface and dynamic microphone sensors. The damage identification method is fractal dimension analyses performed for damaged and non-damaged data, and the alteration of fractal dimensions is investigated. From results, the possibility of application for identifying bridge damage is discussed.

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This paper presents a new system model for diagnosis of structures and facilities based on sounds. In this model, sounds of machines in operation or tapping by a test hammer are recorded as digital data by a PDA or a note-PC and stored in databases in regional administrative offices. Upon request, an inspector or an engineer at a site can retrieve various sound data from the databases via the Web Service by querying. A prototype system was developed. Then, submersible pumps, which are used at inspection galleries of dams, underground power stations, etc., were selected as a target for the verification of verification of the model. We executed experiments by intentionally pasting obstacles between blades of a pump and removing parts of blades and recorded and analyzed the sounds in operation. We found that the deterioration of pumps make differences in spectra of sounds by the spectral analysis. The results showed that the proposed system model could be used for diagnosis of pumps when parts of blades collapsed.

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A prototype of Remote Intelligent Monitoring System (RIMS) was developed for intelligent bridge and infrastructure maintenance. It consists of MEMS sensor, micro-controller with buffer memory and Ethernet controller. Each component is carefully chosen. In the software, TCP/IP and http are adopted in the communication part. The RIMS prototype is a small and relatively inexpensive. It was installed to measure the acceleration of a light pole and its effectiveness was demonstrated.

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For a control problem of wire changing its length such as elevator cables and crane ropes, a controller considering its nonstationary characteristics is effective in suppressing their vibrations. Additionally, the controller having robustness for various uncertainties is valid within suppressing the vibrations of object that has a flexible feature. Consequently, the main objectives of this paper are to propose a nonstationary robust control method and to reduce the transverse vibrations of wire. The vibration controller is designed based on H-infinity theory and a time-varying weighting for the worst disturbance is also optimized to have the appropriate robustness for the parametric uncertainties in time domain. The robust stabilization performances of controller is demonstrated through the numerical calculations and then the robust controller shows the advantage regarding the robustness on the various uncertainties in comparison with the optimal controller.

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Due to various causes, a machine generates dynamic loads during its operation. These dynamic loads are the main source of vibration and noise. If dynamic loads can be identified exactly, it will become possible to provide data effective in reduction of vibration and noise. However, by the method of identification of dynamic loads of the conventional multiple input systems, noise has big influence on the accuracy. Then, in this paper, the identification method using neural network (NN) is proposed for multiple input loads, and the result of these simulations by using these methods are compared in detail.

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In this paper, we first introduced the original OGY method for controlling chaos of a discrete time dynamical system, and the new numerical algorithm of computing the target unstable orbit embedded in chaotic attractor and the approximately linearized subsystem around it of a continuous time dynamical system for applying the OGY method to control the system's chaotic motion, which is named as model-based OGY chaos control method developed by the authors. Then, we took the repulsive type maglev system for an example to discuss the relationship between the phase selection of Poincare map of a continuous dynamical system and its chaotic vibration controller design by model-based OGY method. The results also showed that the suggested model-based OGY chaos control method is a strong tool for applying OGY method to solve chaos control problems in engineering that can be modeled as continuous dynamic systems.

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