Showing papers on "Active vibration control published in 2001"
TL;DR: A review of the research work performed in real-time active balanc- ing and active vibration control for rotating machinery, as well as dynamic modeling and analy- sis techniques of rotor systems, is presented in this article.
Abstract: Vibration suppression of rotating machinery is an important engineering problem. In this paper, a review of the research work performed in real-time active balanc- ing and active vibration control for rotating machinery, as well as the research work on dynamic modeling and analy- sis techniques of rotor systems, is presented. The basic methodology and a brief assessment of major difficulties and future research needs are also provided.
227 citations
Journal Article•
TL;DR: In this paper, a new compensator design method for invertible complex hysteretic nonlinearities that is based on the so-called Prandtl-Ishlinskii hysteresis operator is described.
Abstract: Undesired complex hysteretic nonlinearities are present to a varying degree in virtually all smart-material-based sensors and actuators provided they are driven with sufficiently high amplitudes. In motion and active vibration control applications, for example, these nonlinearities can excite unwanted dynamics, which leads in the best case to reduced system performance and in the worst case to unstable system operation. This necessitates the development of purely phenomenological models that characterize these nonlinearities in a way that is sufficiently accurate, amenable to a compensator design for actuator linearization, and efficient enough for use in real-time applications. To fulfil these demanding requirements, this article describes a new compensator design method for invertible complex hysteretic nonlinearities that is based on the so-called Prandtl-Ishlinskii hysteresis operator. The parameter identification of this model can be formulated as a quadratic optimization problem, which produces the best L 2 2 -norm approximation for the measured output-input data of the real hysteretic nonlinearity. Special linear inequality constraints for the parameters guarantee the unique solvability of the identification problem and the invertability of the identified model. This leads to a robustness of the identification procedure against unknown measurement errors, unknown model errors, and unknown model orders. The corresponding compensator can be directly calculated and thus efficiently implemented from the model by analytical transformation laws. Finally, the compensator design method is used to generate an inverse feedforward controller for the linearization of a magnetostrictive actuator. In comparision to the conventionally controlled magnetostrictive actuator, the nonlinearity error of the inverse controlled magnetostrictive actuator is lowered from about 30% to about 3%.
182 citations
TL;DR: In this paper, the authors considered a plate/shell structure with thin PZT piezoceramic layers embedded on top and bottom surfaces to act as distributed sensor and actuator.
151 citations
TL;DR: In this paper, the effect of the stretching-bending coupling of the piezoelectric sensor/actuator pairs on the system stability of smart composite plates is investigated.
Abstract: This study on the vibration control of smart piezoelectric composite plates investigates the effect of the stretching-bending coupling of the piezoelectric sensor/actuator pairs on the system stability of smart composite plates. Based on first-order shear theory and consistent methodology, a smart isoparametric finite element is formulated and the classical negative velocity feedback control method is adopted for the active vibration control analysis of smart composite plates with bonded or embedded distributed piezoelectric sensors and actuators. It is shown mathematically and demonstrated numerically that generally the coupling effect tends to result in system instability unless the sensor/actuator pairs are collocated or the plate simply supported. The result of this study can be used to aid the placement of piezoelectric sensor/actuator pairs of smart composite plates as well as for robust controller design.
106 citations
TL;DR: In this article, the authors present the design and analysis of the piezoelectric active control of damped sandwich beams, which is done using a specific finite element, able to handle sandwich beams with a laminated surface layers and viscoelastic core.
101 citations
TL;DR: In this article, a novel approach for vibration control of smart plates using discretely distributed piezoelectric actuators and sensors is presented, and the results obtained using the present optimal criteria show that they do not depend on the initial condition of vibration of the structures, nor do they depend on control gains.
Abstract: A novel approach is presented for vibration control of smart plates using discretely distributed piezoelectric actuators and sensors. The new method consists of techniques for designing quasi-modal sensors and quasi-modal actuators. The modal coordinates and the modal velocities are obtained approximately from the outputs of the discretely distributed piezoelectric sensor elements, whereas the modal actuators are implemented by applying proper voltages on each actuator element. The observation error of the modal sensor is analyzed, and an upper bound for the observation error is determined. The control spillover of the modal actuator is also estimated, and an upper bound of the control spillover is also found. The criteria are developed for finding the optimal locations and sizes of both piezoelectric sensor and actuator elements. In the optimality criteria the optimal locations and sizes of the sensor elements can be found by minimizing the observation error of the modal sensor, and those of the actuator elements can be obtained by minimizing both the control energy and the control spillover. The results obtained using the present optimal criteria show that they do not depend on the initial condition of vibration of the structures, nor do they depend on the control gains.
94 citations
TL;DR: In this article, an active microvibration isolation system using voice-coil linear motors and pneumatic and piezoelectric actuators is presented to reduce the six degrees of freedom associated with the rigid body modes of the vibration isolation table by feeding back the pseudo absolute displacement and velocity of the table.
Abstract: This paper presents an active microvibration isolation system using voice-coil linear motors, and pneumatic and piezoelectric actuators. This system is designed to reduce microvibration of the six degrees-of-freedom associated with the rigid body modes of the vibration isolation table by feeding back the pseudo absolute displacement and velocity of the table. To improve vibration isolation performance, a feed-forward control link is added to the sway components in each dimension. This system can also control bending modes of the table in the frequency range up to 200 Hz by employing a proposed Virtual Tuned-Mass Damper control strategy, which is a type of the pole assignment method. In this approach, the pole locations are chosen by a genetic algorithm. For ambient microvibration of the floor around 0.5 cm/s 2 and for small earthquakes of around 8 cm/s 2 a reduction by a factor of 100 was achieved in the acceleration of the vibration isolation table. Moreover, the vibration of the isolation table was decreased over the entire frequency range. This system also showed good vibration control performance when an impact excitation was applied directly to the table; vibration was damped out within about 0.1 sec. Additionally, the resonance amplitudes around the bending modes of the table were reduced from 1/5 to 1/15 by the Virtual Tuned-Mass Damper method.
83 citations
TL;DR: In this article, the authors present a numerical and experimental study of the application of active constrained layer damping to a clamped-clamped plate, where a passive constrained viscoelastic damping layer is augmented with an active scheme employing a PZT patch as the actuator.
83 citations
TL;DR: In this paper, a dynamic vibration absorber is mounted on a cutting tool against vibrations in turning operations, which can reduce the magnitude of the frequency response function of the cutting tool.
81 citations
TL;DR: Experimental results show that up to 14 dB reduction in the kinetic energy of the equipment can be achieved in practice if very high gains are used in the experiments, however, instability occurs at low frequencies due to phase shifts in the transducer conditioning electronics.
Abstract: This paper describes a theoretical and experimental investigation into an active four-mount vibration isolation system, in which electromagnetic actuators are installed in parallel with each of the four passive mounts placed between a three-dimensional piece of equipment and a vibrating base structure. Decentralized velocity feedback control is applied, where each actuator is operated independently by feeding back the corresponding equipment vibration velocity at the same location. Although one end of the actuator acts at the sensor position on the equipment, the system is not collocated because of the reactive force at the other end acting on the flexible base structure, whose dynamics may be strongly coupled with the mounted equipment. The investigation of this actuator installation and its practical implementation are the motivation of this research. Isolation of low-frequency vibration is considered where the equipment can be modeled as a rigid body and the mounts as lumped-parameter springs and dampers. A general theoretical formulation for analysing multiple-mount vibration isolation systems using the impedance method is presented and is used to investigate the control mechanisms involved. Experimental results show that up to 14 dB reduction in the kinetic energy of the equipment can be achieved in practice. If very high gains are used in the experiments, however, instability occurs at low frequencies due to phase shifts in the transducer conditioning electronics.
79 citations
TL;DR: In this article, the authors investigated the effect of debonding on active vibration control of smart beams with piezoelectric sensors and actuators and proposed a novel model, which takes into account both flexural and longitudinal displacements of the host beam and piezelectric layers as well as the peel and shear strains of the adhesive layer.
TL;DR: In this paper, a Vlasov-based finite beam element is developed to model the rotating actuator beam and is validated with the free-vibration and static forced response of 4:1 and 2:1 aspect ratio, bending-torsion coupled, active and passive plates.
Abstract: Active rotorblade tips offer an alternative approach to the challenge of main rotor active vibration control. The tips are pitched with respect to the main blade via a piezo-driven bending-torsion coupled actuator beam that runs down the length of the blade. A Vlasov based, specialized one-dimensional finite beam element is developed to model the rotating actuator beam and is validated with the free-vibration and static forced response of 4:1 and 2:1 aspect ratio, bending-torsion coupled, active and passive plates. A one-eighth scale, reduced tip-speed rotor model (tip Mach 0.26), incorporating the bending-torsion actuator beam, has been previously hover tested (open loop). In these tests, blade tip deflections of the order of 2° (half peak-to-peak) were achieved at 2, 3, 4, 5/rev with corresponding dynamic vertical blade root shear variations of the order of 10-20% of the nominal blade lift at 8° collective (CT/σ = 0.07). The test results are used to validate a coupled actuator and elastic rotorblade model. The correlation of the predicted active blade-tip pitch deflections and the experimental data is within 20%. The predicted values for the active vertical root shears are within the same margin for 4° and 6° collective.
TL;DR: In this paper, a sliding mode observer is used to eliminate observation spillover in the vibration control of flexible structures, and the performance of the observer is compared with a conventional Kalman filter to demonstrate robustness and disturbance decoupling characteristics.
Abstract: The objective of this study is to demonstrate that sliding mode observers can eliminate observation spillover in the vibration control of flexible structures. It is common to build a state feedback controller and a state estimator based on the mathematical model of the system with a finite number of vibration modes, but this may cause control and observation spillover due to the residual (uncontrolled) modes. This paper deals with the elimination of observation spillover using a sliding mode observer. The performance of a sliding mode observer is compared with that of a conventional Kalman filter to demonstrate robustness and disturbance decoupling characteristics. Simulation and experimental results using the sliding mode observer are presented for active vibration control of a cantilever beam.
TL;DR: In this article, a finite composite beam element with piezoelectric actuators and sensors is used to model the active vibration control of beam structures equipped with PDEs.
Abstract: The active damping of structures is an important emerging field. In this context, it is necessary to be able to develop new control methods for flexible structures and simulate their effects. In order to be able to deal with the optimization of active device locations, spillover and any other general problems linked to control and model reduction, a simple but sufficiently rich model is very useful. This is the reason why this technical note deals with the modeling and simulation of the active vibration control of beam structures using piezoelectric actuators and sensors. In order to model beam structures equipped with piezoelectric devices, we develop a simple finite composite beam element, taking into account the properties of piezoelectric elements. This model uses six mechanical degrees of freedom and four electric degrees of freedom. Then, a linear quadratic regulator method is used to compute the control, including the implementation of a state observer. Several simulations are presented.
01 Aug 2001
TL;DR: In this article, a magnetic damper system using a phase-lead controller is used to reduce the vibration of a one-degree-of-freedom suspension system, and an accurate transfer function for the total system is determined using an error minimization method.
Abstract: This paper is concerned with the design and implementation of a magnetic damper system to reduce the vibration of a suspension system actively. A cylindrical-type electromagnetic actuator with a permanent magnet is analysed and an effective controller design is made. An accurate force analysis is carried out for the given system. An accurate transfer function for the total system is determined by experimental data using an error minimization method. For experiments, a simple suspension structure system is utilized, in which a magnetic damper composed of a permanent magnet and digital controller is attached. In order to drive the system, a bipolar power amplifier of the voltage control type is utilized. A stable and high speed control board is used to implement digital control logic for the given system. This paper shows that the magnetic damper system using a phase lead controller is excellent in reducing the vibration of a one-degree-of-freedom suspension system.
TL;DR: In this article, an analytical formulation is derived for modeling the behavior of laminated composite beams with integrated piezoelectric sensor and actuator, which is applicable for both thin and moderately beams, and includes the coupling between mechanical and electrical deformations.
TL;DR: In this article, a quasi-modal sensor is developed to estimate the dominant mode coordinates of the shell from the outputs of the sensor patches, and a criterion for finding the optimal locations and sizes of sensor elements is given by minimizing the observation spillover.
TL;DR: In this article, an inertial load is driven by using an actuator, and the actuator fixed to a structure such as a vibration isolation base, an apparatus mounted on the base, and a control force is applied to the structure by using a drive reaction force generated upon driving of the inertial loads, thereby stably and quickly suppressing produced vibrations.
Abstract: In precision equipment such as a semiconductor exposure apparatus, an inertial load is driven by using an actuator, and an actuator fixed to a structure such as a vibration isolation base, an apparatus mounted on the base, and a control force is applied to the structure by using a drive reaction force generated upon driving of the inertial load, thereby stably and quickly suppressing produced vibrations.
Book•
01 Nov 2001TL;DR: In this article, the kinematics of vibration and acoustics fundamentals of structural dynamics vibration of structures in quiescent fluid were discussed, including vortex-induced vibration fluid-elastic instability of tube bundles turbulence induced vibration in parallel flow turbulenceinduced vibration in cross-flow axial and leakage-flow induced vibrations impact, fatigue and wear acoustically induced vibration and noise signal analysis and diagnostic techniques.
Abstract: Units and dimensions the kinematics of vibration and acoustics fundamentals of structural dynamics vibration of structures in quiescent fluid 1 - the hydrodynamic mass vibration of structures in quiescent fluids 2 - simplified methods vortex-induced vibration fluid-elastic instability of tube bundles turbulence-induced vibration in parallel flow turbulence-induced vibration in cross-flow axial and leakage-flow induced vibrations impact, fatigue and wear acoustically induced vibration and noise signal analysis and diagnostic techniques.
TL;DR: In this paper, a modal controller is implemented on a digital controller board and experimental tests with the floor panel and center panel of a car body are carried out to validate the proposed concept.
TL;DR: In this paper, the dynamics of friction-induced vibration resulting from a velocity-dependent friction characteristic is studied theoretically and experimentally, and the amplitude of quasi-harmonic vibration is shown to increase with sliding velocity until oscillation ceases at some upper velocity boundary depending on the friction characteristic.
TL;DR: A two-degree-of-freedom model has been constructed for a structural dynamic system consisting of a linear elastic plate bonded with piezoelectric sensors and actuators and four control procedures based on the minimization of performance output error and the quadratic performance index have been developed.
Abstract: In this paper, a two-degree-of-freedom model has been constructed for a structural dynamic system consisting of a linear elastic plate bonded with piezoelectric sensors and actuators. A multivariable feedback controller is designed. Four control procedures based on the minimization of performance output error and the quadratic performance index have been developed that use rate-feedback control, hybrid fuzzy-PID con trol, genetic algorithms-designed PID control, and linear quadratic Gaussian/loop transfer recovery control methods. Here, the genetic algorithm fitness function is approximately proportional to the inverse of the out put error. To test these control techniques in an efficient and systematic way, we built a digital control system that consists of MATLAB/SIMULINK modeling software and a dSPACE DS 2100 controller in a personal computer. The real-time experiment and off-line simulation results confirm that these four kinds of control methods are reliable and efficient in suppression of the steady...
01 May 2001
TL;DR: In this article, the authors consider the future interferometric missions planned by NASA or ESA (one such a mission, called ”Terrestrial Planet Finder” aims at detecting earth-sized planets outside the solar system; other missions include the mapping of the sky with an accuracy one order better than that achieved by Hypparcos).
Abstract: In order to motivate the use of active vibration control, consider the future interferometric missions planned by NASA or ESA (one such a mission, called ”Terrestrial Planet Finder” aims at detecting earth-sized planets outside the solar system; other missions include the mapping of the sky with an accuracy one order better than that achieved by Hypparcos) The purpose is to use a number of smaller telescopes as an interferometer to achieve a resolution which could only be achieved with a much larger monolythic telescope One possible spacecraft architecture for such an interferometric mission is represented in Fig1; it consists of a main truss supporting a set of independently pointing telescopes
TL;DR: In this paper, the active vibration control of smart/intelligent shells with a distributed piezoelectric sensor and actuator layer bonded onto the top and bottom surfaces of the structures is investigated.
Abstract: Smart/intelligent/adaptive structures with distributed, integrated sensors, actuators and control electronics are being investigated extensively for possible use in high-performance, light-weight structural systems. Due to the unique electromechanical coupling, these piezoelectric materials could be used as sensors and actuators in smart structures. This work deals with the active vibration control of smart/intelligent shells with a distributed piezoelectric sensor and actuator layer bonded onto the top and bottom surfaces of the structures. A shear-flexible nine-noded shell finite element derived from the field consistency approach has been used for the investigation. This element has been developed so as to have one electrical degree of freedom per piezoelectric layer per element. The mass, stiffness and electromechanical coupling effects of the piezoelectric sensor and actuator layer are considered. The control performance with different types of loading is investigated. A linear quadratic regulator optimal control scheme is used to obtain the control gains.
TL;DR: In this paper, a double-acting shock absorber with vibration isolation capabilities is used to attenuate the effects of vibration on the mass of the mass and adjacent walls of the frame so that shock and vibrations moving along the vertical, horizontal and longitudinal axes are effectively attenuated.
Abstract: A shock and vibration isolator system that includes a frame in which a shock and vibration sensitive mass is suspended by double acting shock absorbers with vibration isolation capabilities. Wire rope isolators are also mounted between walls of the mass and adjacent walls of the frame so that shock and vibrations moving along the vertical, horizontal and longitudinal axes of the system are effectively attenuated.
TL;DR: In this article, a self-adapting vibration control system for damping augmentation in smart composite beams is developed, which consists of a dynamic diagonal recurrent neural network (DRNN) and an adaptable feed forward neural network.
Patent•
27 Aug 2001
TL;DR: In this article, the authors proposed a vibration chip that can stabilize dispersion in the CI (Crystal Impedance) and the temperature characteristics among vibration chips and can be downsized and to provide a vibrator employing the vibration chip, an oscillator and an electronic device.
Abstract: PROBLEM TO BE SOLVED: To provide a vibration chip that can stabilize dispersion in the CI (Crystal Impedance) and the temperature characteristics among vibration chips and can be downsized and to provide a vibrator employing the vibration chip, an oscillator and an electronic device. SOLUTION: The vibration chip 100 is configured with a base 110 comprising a plurality of vibration arms projected from the base by being projected from the base, in which grooves 121a, 122a are formed to a front and/or a rear part of each of the vibration arms 121, 122, arm widths 121c, 122c of each vibration arm in a short side direction in the front and/or the rear part of each vibration arm are formed to be about 50 μm to about 150 μm, an interval 125 between the vibration arms in the arm width direction is formed to be the arm width plus about 50 μm or below, and a length 110c of the base in the width direction is nearly the same as or slightly longer than the length of the sum of the arm widths of a plurality of the vibration arms and the internal in the width direction. COPYRIGHT: (C)2003,JPO
TL;DR: In this article, a hybrid wave/mode active vibration control is described with specific reference to the control of a cantilever beam, where wave control is first applied at one or more points in the structure and then modal control is applied, being designed on the basis of the modified global equations of motion of the structure-plus-wave controller.
TL;DR: In this paper, the performance of traditional piezoelectric transducers with newly designed Flextensional transducers is compared, and the authors compare their performance with those of actuators with high-displacement, high generative force, and quick response time.
Abstract: Smart electromechanical systems consist mainly of sensors, actuators, and data processing units. Actuators are the responding units of many smart systems including those for active vibration control and noise control. Increased demand for actuators with high-displacement, high generative force, and quick-response time has led to a search for new actuator materials and new designs. The performance of traditional piezoelectric transducers with newly designed flextensional transducers is compared.
TL;DR: In this paper, a speed-varying transient rigid rotor model is developed in the state space form and the states of this model are augmented to include imbalance forces and moments.
Abstract: Rigid rotor dynamic model is widely used to model rotating machinery. In this paper, a speed-varying transient rigid rotor model is developed in the state space form. The states of this model are augmented to include imbalance forces and moments. A time-varying observer can then be designed for the augmented system by using canonical transformation. After obtaining an estimation of the imbalance forces and moments as the states of the augmented system, the estimated imbalance can be directly calculated. This estimation method can be used in the active vibration control or active balancing schemes for a rigid rotor.