Vibration Control Of Structural Systems Research Articles

Free Vibration of Thermally Loaded FG-GPLRC Nanoplates Integrated with Magneto-Electro-Elastic Layers in Contact with Fluid

This work investigates the free vibrations of innovative thermally loaded nanoplates constructed by integrating magneto-electro-elastic (MEE) layers with functionally-graded graphene platelet-reinforced composite cores (FG-GPLRC) and accounting for viscous fluid interactions. An advanced multiphysics model is developed using the Navier–Stokes equations to capture fluid structure coupling effects, Halpin–Tsai, and the rule of mixtures micromechanics to predict the non-uniform effective properties, third-order shear deformation plates theory (TSDPT) to incorporate thickness stretching, and the nonlocal strain gradient theory (NSGT) to characterize size dependencies. The Galerkin technique is used to solve the governing equations, which are derived from the Hamilton’s principle. Parametric analyses quantify the influences of fluid depth, temperature fluctuations, temperature profiles, nonlocal and strain gradient parameters, electric and magnetic potentials, graphene distribution patterns, graphene weight fractions, and boundary conditions on the vibration response. The outcomes of this study provide design guidelines and predictive tools enabling active vibration control systems for next-generation thermally-loaded nanocomposite structures with widespread applications from aerospace vehicles to nanoelectronics.

Newly Constructed Subway on Over-Track Bridge Safety and Vibration Reduction Measure

Primarily generated at the interface between the wheel and the rail, railroad vibrations then propagate through the supporting soil. If these vibrations reach nearby bridges and buildings, they amplify the vibration nuisance and cause ground noise, which has detrimental effects on nearby residents, sensitive equipment, and historic structures. By analyzing measured data from metro vibration field vibration experiments, this article attempts to contribute to the body of knowledge on environmental vibration propagation patterns by offering insightful conclusions. Before analyzing the deformation response of the metro jet system (MJS) vibration isolation piles to the structure and the ground, we investigated the effect of MJS vibration isolation piles in the ground of the existing subway tunnel structure on the control of vibration of the proximate structure and conducted dynamic tests on the vibration of bridges without vibration isolation measures caused by operating subway trains. The tests determined that the acceleration of the bridge’s lateral vibration exceeded the code limit; one of the contributing factors was that the bridge’s structure had already sustained damage. The utilization of MJS isolation piles was also discovered to safeguard the extant bridge pile foundations. The paper presents an innovation in the form of economically viable vibration mitigation strategies that were implemented subsequent to the identification that the lateral vibration acceleration of the preexisting bridge surpassed the prescribed code standards. Considerable insight is gained regarding the design and implementation of vibration control systems for structures situated near caverns, encompassing deep foundation works.

State Observing Method and Active Vibration Control Based on Virtual Sensing

State feedback is mostly used in the active vibration control of structural systems. However, the most challenging problem is to achieve the whole state of the structure. Another issue in active vibration control is that, in many cases, only some particular modes need to be controlled, while the other modes can remain unchanged in order to save on the costs of the control. To solve the above issues, this paper proposes a state-observing method and conducts a non-spillover partial pole placement control using a multistep method. Using the finite element method, the electromechanical coupling equations of motion of the beam are formulated. The reduced finite element model is then obtained by using the system equivalent reduction expansion process method. Introducing the real measurements by sensors and applying the local corresponding principle, the modes of the structural system are corrected, which are then utilized to predict all the degrees of freedom without measuring by sensors. Then, the non-spillover partial pole placement based on the state feedback is conducted using the multistep method. The optimal locations of actuators are derived by the genetic algorithm to control the specific structural modes effectively. The numerical simulations and experimental studies are also carried out.

Magnetorheological Damper Force Prediction using Particle Swarm Optimization and Long Short-Term Memory Model

Smart materials, like magnetorheological (MR) fluid, are gaining attention for their ability to rapidly change properties under magnetic influence, making them useful in vibration control systems for vehicles, medical devices, and civil engineering structures. Common parametric models, such as Bouc-Wen and Bingham, are traditionally employed to model MR damper dynamics behavior. However, the manual tuning of numerous parameters in these models increases complexity and hinders the identification of inverse models, potentially leading to unpredictable optimum target forces. In response to these challenges, this study suggested a non-parametric approach using Long Short-Term Memory (LSTM) models to predict the optimum target force of MR dampers. Unlike parametric models, LSTM models capture dynamic behavior without the need for extensive manual tuning. To optimize the LSTM model, Particle Swarm Optimization (PSO) is employed to fine-tune hyperparameter values, ensuring robust performance. The proposed non-parametric method, specifically the PSO-LSTM model, demonstrates faster processing times compared to traditional parametric approaches. The proposed model produced an accurate damping force prediction with a root mean square error of less than 5%, This novel approach simplifies the modeling process and offers an efficient and precise alternative to traditional parametric methods.

Editorial: Energy dissipation devices and vibration-control systems for structures and infrastructures to mitigate damages under different hazards

Editorial: Energy dissipation devices and vibration-control systems for structures and infrastructures to mitigate damages under different hazards

Enhancing the Seismic Performance of Adjacent Building Structures Based on TVMD and NSAD

Under the action of an earthquake, the adjacent building structure will have a large displacement and even cause damage to the structure. Structure displacement can be suppressed by adding a tuned viscous mass damper (TVMD) and negative stiffness amplifier damper (NSAD) between adjacent structures. This paper deduces the motion equation of adjacent building structures under earthquake action. The transfer function of the vibration control system is obtained using Laplace transform. The parameter optimization analysis of the structural vibration control system is carried out through H2 norm theory. The vibration control performance of the TVMD vibration control system and NSAD vibration control system is studied by taking two adjacent building structures composed of single freedom building structures as an example. The results show that the two vibration damping devices proposed in this paper can play the role of vibration control. The influence of the same parameters on the two structures is not completely consistent. Under seismic excitation, the NSAD control system has better displacement control ability than the TVMD control system.

Structural Vibration Suppression Using a Reduced-Order Extended State Observer-Based Nonsingular Terminal Sliding Mode Controller with an Inertial Actuator

In this paper, we mainly aimed to design a reduced-order extended state observer-based active vibration controller for a structural vibration control system with total disturbances, i.e., model uncertainties, higher harmonics, and external excitations. A reduced-order extended state observer (RESO)-based nonsingular terminal sliding mode vibration control (RESO–NTSMVC) method is proposed for the vibration suppression of an all-clamped plate structure with an inertial actuator. First, a second-order state space model of the thin plate, with an inertial actuator, was established by solving the dynamic partial differential equation and analyzing the physical model. Second, the total disturbances, i.e., model uncertainties, higher harmonics, and external excitations, were estimated and compensated for by using a RESO via a feedforward part. Third, a NTSMVC based on an estimated value was designed to obtain a fast-tracking rate and effective vibration suppression performance. In addition, the stability of the closed-loop system was proven by using a Lyapunov stability criterion. Finally, a semi-physical experimental instrument was built based on the MATLAB/Simulink real-time environment and the NI-PCIE6343 acquisition card to verify strong anti-disturbance performance and effective vibration control performance of the designed method. The experimental comparison results showed that the vibration amplitudes of the proposed method could be reduced by 11.7 dB, when the traditional extended state observer-based nonsingular terminal sliding mode vibration control (ESO–NTSMVC) method achieved a control effect of only 6.5 dB. The comparative experimental results showed that the proposed method possessed better vibration suppression performance and anti-disturbance performance.

Nonlinear ESO-based vibration control for an all-clamped piezoelectric plate with disturbances and time delay: Design and hardware implementation

Considering the problems of model uncertainties, higher harmonics, uncertain boundary conditions, external excitations, and system time delay in practical vibration control system, a novel active vibration control method is proposed to suppress the vibration of a thin plate structure with acceleration sensor and piezoelectric bimorph actuator in this paper. First, a nonlinear extended state observer (NESO)-based controller is designed to ensure the anti-disturbance performance of the structural vibration control system. Then, an enhanced differentiator-based time delay compensation method is introduced to improve the vibration suppression performance of the NESO-based controller. A real time hardware-in-the-loop benchmark for an all-clamped piezoelectric thin plate is designed to verify and compare the performance of the developed controller against conventional ESO-based methods (linear ESO with/without time delay compensation, NESO without time compensation). The best vibration suppression and disturbance rejection performance of the proposed NESO-based controller with an enhanced time delay compensator is verified in the comparative experimental results. This work is able to provide practitioners with vital guidance in designing active vibration control system in the presence of disturbances and time delay.

Semi-active vibration control of structural systems with a variable inerter

We propose a design method of semi-active vibration control systems using a variable inerter for structural systems subject to seismic disturbances. The inerter is a vibration control device generating resistance force proportional to the relative acceleration between both ends. In the variable inerter, the inertia mass of the inerter can be changed by a command signal in realtime. The mathematical model of the variable inerter is defined considering the dynamic delay of the inertia mass change subject to the command signal. For the dynamic model of a structural system with the variable inerter, we propose a semi-active control law based on a reference active control system. The reference active control system is a virtual system showing the ideal control performance. In the proposed semi-active control law, the variable inertia mass is changed by considering a predicted control output, the predicted error between the control output of the semi-active and reference active control systems, and the predicted reaction force of the inerter. The characteristic of the reference active control is optimized so that the control performance of the resulting semi-active control system is close to that of the best control systems among the passive off (without control), passive on (maximum inertia mass), and reference active control systems. A simulation study shows the effectiveness of the proposed semi-active control method.

Research of active vibration control optimal disposition based on CMQPSO

The adaptive quantum particle swarm optimization algorithm based on cloud model and the multi-island genetic algorithm [15] have obvious advantages in convergence speed to solve the sensor optimization problem, and can effectively achieve global optimization. Due to the installation of sensors and actuators, the electromechanical coupling coefficient of intelligent structures is changed, which affects the vibration energy of structures. In this paper, the reserved energy index of structural vibration control system is taken as the objective optimization function. The position, number, length and control gain of sensors and actuators of active vibration control system are optimized. The adaptive Quantum-behaved Particle Swarm Optimization algorithm in cloud model(CMQPSO) is used as the optimization strategy, and the cantilever beam is taken as an example. This approach is verified its effectiveness and feasibility. It is found that excellent optimization results are obtained.

Multi-electrode layout design of electrorheological composite plates considering energy consumption in semi-active control

In the semi-active vibration control of structural systems, best control performance and low energy consumption both play important roles. This paper presents a new topology optimization method for the multi-electrode layout design of sandwich electrorheological (ER) plates considering limited energy consumption under different vibration conditions. In the proposed topology optimization model, the dynamic compliance under specified harmonic excitation is taken as the objective function, and a constraint of the maximum allowable energy consumption is considered. The frequency response analysis is implemented with finite element discretization, and the sensitivity analysis scheme of the control energy consumption for the design variables is derived with the adjoint-variable method. Numerical examples showed that optimal layouts of multi-electrodes could be obtained with different energy consumption requirements and loading conditions by using the proposed method. The excellent performance of vibration control could be achieved by only varying the voltage distribution of ERs.

A Computationally Efficient Method for Optimum Tuning of Single-Sided Pounding Tuned Mass Dampers for Structural Vibration Control

Pounding tuned mass dampers (PTMD), which relies on impact to dissipate vibration energy, have shown remarkable performance in suppressing structural vibrations with its modest design. However, the optimum design of PTMDs is computationally expensive due to non-smooth contact-impact behavior. This study provides a computationally efficient approach to determine the optimal parameters of single-sided PTMDs used in vibration control of structural systems. An optimization strategy is used to minimize the maximum response of the controlled structure. As is well-known, the calculation of the dynamic response of a structure could be cumbersome when conventional time-stepping techniques are used in each iteration of the optimization routine. Hence, an exact analytical solution of the steady-state vibration is used to calculate the response for different excitation frequencies, which substantially decreases the computational burden. The adopted method is computationally very inexpensive with respect to the conventional time-stepping techniques used to solve the nonlinear equations of motion to obtain response quantities. The exact solution only requires the solution of the system of five nonlinear equations in order to evaluate the steady-state response per each excitation frequency of harmonic force. A four-storey shear building is used to evaluate the optimally-tuned PTMD by the proposed procedure. In addition, simplified design equations for the coefficient of restitution and frequency ratio are provided using curve and surface fitting for preliminary design. It was shown that the effect of damping ratio of the primary structure on the optimal coefficient of restitution value is not considerable, while it has significant influence on the optimal frequency ratio. It was also realized that the objective function used in optimum parameter design has only one local optimum, which is suitable for the application of gradient-based optimization methods.

Rate dependent free energy formulations for dynamically excited superelastic SMA wires

AbstractSuperelastic shape memory alloys (SMAs) are metallic two‐phase polycrystal alloys. The transformation between austenite and martensite phases allows superelastic SMAs unique hysteretic energy dissipation capacity, which is particularly interesting for the development of new‐type of intelligent vibration control systems for structures. However, in structural control, most of the vibrations occur in high strain rate regimes, which interfere the release of self‐generated heat and cause atomic lattice destabilization and thus influence the hysteretic dissipation. The present work proposes two different strain rate dependent free energy formulations and aims to improve the accuracy of existing one‐dimensional macroscopic models of SMA wires. The approaches are developed and implemented in different continuum thermomechanical frameworks, without impairing the simplicity and robustness of the solution process. The first approach introduces an additional control variable for the entropy evolution. The second approach uses a phenomenological formulation of the latent heat evolution. The proposed formulations are validated by cyclic tensile tests conducted on SMA wires. The results show that the calculations using the new formulations can represent the superelastic SMA wire response more accurately.

Preview Type Active Vibration Control of Structural Systems with the Waveform Information of Remote Observation Sites

Preview Type Active Vibration Control of Structural Systems with the Waveform Information of Remote Observation Sites

Semi-active vibration control of structural systems with a neural network that trained preview optimal control for MLD model

We propose a new semi-active vibration control method of structural systems subject to seismic disturbances based on the optimal control for MLD models incorporating future seismic waveforms. In the proposed preview control method, we aim to realize the higher control performance than the conventional predictive control for the MLD model by considering future seismic waveforms. In the preview control law for the MLD model, a future data series of the seismic waveform is necessary. Because the future seismic waveform is not available, the method is generally impossible. In this paper, the control input data of the preview optimal control of the MLD model using future seismic waveforms are collected in advance subject to the recoded seismic waves, and the control inputs are trained with a multi-layered artificial neural network by using the past seismic waveforms. By replacing the preview optimal control for MLD model with the neural network, we are able to construct an implementable preview control system that shows high control performance using past seismic waveforms. Besides, the conventional method to obtain the control inputs of optimal control for MLD model has a problem on the high computational load, because it is MIQP that is NP-hard problem to obtain control inputs. Therefore, there are two difficulties in the real time implementation of the control method. By using the proposed neural network as the control law, the problem on the computational load can also be solved. The effectiveness of the proposed method is confirmed by a simulation using seismic waveforms observed in Japan. In the simulation study, the high control performance and the reduction of the computational load are demonstrated in comparison with implementable conventional methods.

Strain rate dependent formulation of the latent heat evolution of superelastic shape memory alloy wires incorporated in multistory frame structures

Due to their unique hysteretic energy dissipation capacity, shape memory alloy (SMA) wires are particularly interesting for the development of new-type of intelligent vibration control systems for structures. However, in structural control, most of the vibrations occur in high strain rate regimes, which interfere the release of self-generated heat and thus influence the hysteretic dissipation. This paper proposes a strain rate dependent formulation of the latent heat evolution and aims to improve the accuracy of existing macroscopic modeling approaches developed for SMA wires particularly for the dynamic load cases. The proposed formulation is determined phenomenologically and implemented in a continuum thermomechanical framework based constitutive SMA wire model without impairing the simplicity and robustness of the solution process. The proposed formulation is validated by cyclic tensile tests conducted on SMA wires. Results show that the calculations using the formulation can predict the wire response more accurately than the strain rate independent formulation. For the simulation of multistory frame structures incorporating multiple SMA wires, the governing equations are driven. Shaking table tests are conducted on a 3-story frame structure under harmonic and seismic excitation. The responses of the structure are successfully replicated using the strain rate dependent latent heat formulation.

Active vibration control of structural systems with a preview of a future seismic waveform generated by remote waveform observation data and an artificial intelligence–based waveform estimation system

We propose a new active vibration control strategy of structural systems based on the information of future seismic waveform observed in remote observation sites. The observed waveform information of the remote site is transmitted by a waveform transmission network to the structure under control. The waveform transmission network is realized by interconnecting multiple controlled structures and observation sites. By using the remote waveform containing the future information of the disturbance at the location of the controlled structure, we propose an active control method that achieves fairly higher control performance over conventional methodologies. A preview control consisting of the state-feedback and feedforward control (preview action) is adopted as the control law. For the preview action, a future seismic waveform in some time interval is needed. Because the future seismic waveform is not available, the preview action contributing the performance improvement is generally impossible. To get over this difficulty, an artificial intelligence–based waveform estimation system to estimate the future seismic waveform is proposed. The core of the wave estimation system is a multi-layered artificial neural network. Through a small-scale simulation study with a recorded seismic event in Japan, we show that the proposed control method achieves much higher control performance over the optimized state-feedback control law.

Semi-active vibration control of structural systems based on linear approximation of switched linear system

For vibration control of structural system, semi-active control is expected to show better performance than other control methods in terms of energy efficiency. However, because of the energy dissipation characteristics of the semi-active control devices, the mathematical model of the semi-active control system becomes a hybrid model. Optimal control of hybrid models can be solved by mixed integer quadratic programming. However, this method is computationally expensive because the optimization problem must be solved for every sampling instant. One such computationally inexpensive method is clipped-optimal control, but its performance is not guaranteed because it does not consider the constraints of energy dissipation of the semi-active device. The clipped-optimal control can be expressed as a switching system of three systems under the influence of energy dissipation constraints. In a 1-DOF (degree of freedom) system, the switching conditions of the three systems can be expressed as angles on a phase plane. The 1-DOF vibration system draws an ellipse in the forced vibration and a spiral in an initial response on the phase plane. In the case of a vibration system that draws a circle-like trajectory on the phase plane, unlike other switching systems, the selection of these three systems is performed at a substantially constant rate. In this study, we propose a semi-active control method using a single linear system composed of the above three systems. The linear systems are referred to as the averaged systems in the study. We propose a method to systematically design the clipped-optimal control, which has been conventionally designed by trial and error, with the averaged system. Simulation studies show the effectiveness of the proposed semi-active control approach.

Semi-active vibration control for structural systems with a variable inertia mass damper

Semi-active vibration control for structural systems with a variable inertia mass damper

Semi-active vibration control of structural systems by an inertial mass damper

Semi-active vibration control of structural systems by an inertial mass damper