Vibration Control System Research Articles

Bidirectional energy‐controlled piezoelectric shunt damping technology and its vibration attenuation performance

AbstractPiezoelectric material‐based semi‐active vibration control systems may effectively suppress vibration amplitude without any external power supply, or even harvest electrical energy. This bidirectional electrical energy control phenomenon is theoretically introduced and validated in this paper. A flyback transformer‐based switching piezoelectric shunt circuit that can extract energy from or inject energy into piezoelectric elements is proposed. The analytical expressions of the controlled energy and the corresponding vibration attenuation are therefore derived for a classical electromechanical cantilever beam. Theoretical predictions validated by the experimental results show that the structure vibration attenuation can be tuned from −5 to −25 dB under the given electrical quality factor of the circuit and figure of merit of the electromechanical structure, and the consumed power is in the range of −13 to 25 mW, which is a good theoretical basis for the development of self‐sensing, self‐adapting, and self‐powered piezoelectric vibration control systems.

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.

Stability Analysis and Design of n-DOF Vibration Systems Containing Both Semi-Active and Passive Mechanical Controllers.

This paper is concerned with the stability analysis and design of the n-DOF (n-degree-of-freedom) mass-chain vibration systems containing both semi-active and passive mechanical controllers. Based on Lyapunov's stability theory, sufficient conditions are derived for the n-DOF vibration system containing a semi-active switched inerter and a passive mechanical network with the first-order admittance to be globally asymptotically stable. Furthermore, the optimization designs of a quarter-car vibration control system and a three-storey building vibration system are conducted together with the derived stability results, and the instability cases contradicting the stability conditions are presented for illustration. The optimization and simulation results show that the combination of semi-active and passive mechanical controllers in vibration systems can clearly enhance system performances in comparison with the conventional semi-active or passive control. The novelty of this paper is that the stability problem of a general n-DOF vibration system that simultaneously contains a semi-active controller and a first-order passive controller is investigated for the first time, where such a system combines the advantages of both semi-active and passive mechanical controllers. The investigations and results can provide an essential foundation for further exploring the stability problems of more general systems, and can be applied to the controller designs of many vibration systems in practice.

A novel Horizontal Bidirectional Hybrid Damping System (HBHDS) for multi-level vibration control of long-span bridges: A theoretical study

This study develops a novel Horizontal Bidirectional Hybrid Damping System (HBHDS) for mitigating the vibration of long-span bridges. It consists of eddy current dampers (ECDs), metallic yielding dampers (MYDs), fuse-lock device (FLD), and a spherical steel bearing (SSB). The ECD and MYD are connected in series through the FLD along the longitudinal direction to form an integrated passive control system together with the SSB. This system can not only mitigate the vibrations caused by service and seismic loads in the longitudinal direction, but also reduce the bridge seismic response when experiencing an earthquake in the transverse direction. The mechanical model of the HBHDS is introduced, and the method for determining the parameters of the HBHDS is given. To verify the superiority of the proposed HBHDS, a case study is performed on a long-span cable-stayed bridge. The numerical results confirm that the HBHDS has an excellent multi-level vibration control capacity, i.e., it can effectively mitigate structural vibrations caused by moving vehicle as well as earthquakes.

Nonlinear vibration control of magnetic bearing system considering positive and negative stiffness

The nonlinear dynamics are studied for an active magnetic bearing (AMB) system under the low-frequency sinusoidal excitation, which can affect the operational stability of a high-speed magnetic bearing. A single-degree-of-freedom nonlinear dynamics model of magnetic bearing was developed with a c-type active magnetic bearing as the research target. The characteristics of the magnetic bearing system show positive and negative stiffness for different feedback gains. The amplitude–frequency response curves of the vibration characteristics of the positive stiffness magnetic bearing system were obtained by using the method of multiple scales. The influence of each parameter on the resonance amplitude and nonlinearity of the magnetic bearing system is understood by analyzing the amplitude–frequency response curve. The bifurcation diagram for the rotor with rotor mass, and control parameters is derived from the numerical simulation of the negative stiffness magnetic bearing system. The parameter intervals that cause single-cycle vibration, double-cycle vibration, and chaotic state of the magnetic bearing rotor are discovered by analyzing the bifurcation diagrams of each parameter. The simulation results show that the magnetic bearing system exhibits complex nonlinear dynamic characteristics when it is a negative stiffness system.

Modal signal analysis of parabolic shell structures with flexoelectric sensors

The flexoelectric effect, garnering extensive attention in recent years, is an electro-mechanical coupled gradient effect that widely exists in dielectric materials and holds great potential for applications in structural sensing and actuation. The parabolic shell structure, characterized by line focusing, finds widespread use in key structural components such as solar trough collectors and communication antennas. Distributed sensing of the structural states of these parabolic shells is critical for vibration control, health monitoring, and shape control of precision structural systems. Therefore, flexoelectric sensing research based on parabolic shell structure has become an important topic. This study establishes a mathematical model for flexoelectric sensing in a parabolic shell with four-sided simply supported boundary conditions. The model is based on the direct flexoelectric effect, and thin shell assumption, and incorporates specific Lamé parameters and curvature radius. The electro-mechanical strain gradient/signal generation characteristics and distributed modal flexoelectric signals on the parabolic shell are investigated. The sensing signal under the open-circuit conditions is deduced, and the flexoelectric sensing signal and sensing characteristics of different modes are analyzed. The formulation of the flexoelectric neural sensing signal for the parabolic shell structure is provided and divided into two components: a circumferential bending component and a longitudinal bending component. In the case studies, the effects of design parameters such as flexoelectric sensor thickness, size, and aspect ratios are evaluated and compared. The analysis and results of this study offer a theoretical foundation and reference for refining the design parameters of the flexoelectric sensor and determining its optimal sensing position, and potentially paving the way for new applications of flexoelectric sensing technology.

Vibration control of inerter-enhanced mega sub-controlled structure system (MSCSS) and the reliability analysis of the structure under seismic action

This paper studies the novel vibration control of an inerter-enhanced mega sub-controlled structure system (MSCSS). The seismic response of MSCSS is investigated using a tuned viscous mass damper inerter (TVMDI) and compared with existing control methods. This novel strategy evaluates two kinds of TVMDIs on MSCSS, including the inter-story TVMDI, where the TVMDIs are installed inter-story, and the outrigger-based TVMDI, where the TVMDIs are vertically connected between the outrigger and the perimeter of the MSCSS's column to achieve significant energy dissipation. First, a finite element model of MSCSS is established and validated with the experimental model of MSCSS. The governing equation of the enhanced MSCSS is derived from the uncontrolled model. Subsequently, the MSCSS equipped with TVMDIs is thoroughly examined and compared to the existing methods. The effectiveness of the proposed strategy subject to ground motion records via the numerical analysis method is also demonstrated. Finally, the reliability analysis of the enhanced MSCSS based on the probability density function is presented. Results from the numerical investigation of the MSCSS enhanced strategies have revealed that the inter-story and outrigger TVMDI system generally improved the response effectiveness of MSCSS better than the viscous damper (VD) and middle story isolation (MSI) systems. However, the outrigger TVMDI enhanced mega frames control effectiveness more effectively than the story-based TVMDI, whereas the latter is more suitable for substructures.

Comprehensive design optimization of vertical seismic absorbers incorporating sensitivity and robust analysis: A case study of the KDamper

This study presents a comprehensive design optimization approach for building vibration control systems, demonstrated through a case study on the KDamper implemented as a vertical seismic absorber (VSA). The methodology encompasses a series of steps to identify the most suitable VSA design while maximizing the utilization of available resources and considering model and reality imperfections. The outcomes of this investigation include a Pareto front featuring optimal structures and a set of design guidelines specifically tailored for the development of a VSA system. Moreover, optimization analyses conducted on simplified systems have revealed their potential effectiveness even without certain components. Furthermore, a bi-objective robust optimization has demonstrated the system’s resilience to manufacturing uncertainties prevalent in real-world scenarios. Finally, this approach has yielded more consistent system performance than conventional optimization approaches. The proposed methodology holds broad applicability to diverse systems, offering valuable support in achieving widespread utilization and facilitating the design of optimal structures, such as the vibration-absorption system examined in this study.

Vibration control of an eleven-story structure with MR and TMD dampers using MAC predictive control, considering nonlinear behavior and time delay in the control system

In the last two decades, model predictive control has made significant progress in research and industrial process control. This achievement is through the high ability of model predictive control to solve industrial process control problems in the time domain. It is applicable in many control systems, such as delayed systems, univariate and multivariable systems, non-minimum phase systems, and unstable systems. This strategy is essentially for controlling delayed systems. It is possible to create a time delay in transmitting structure movement data in the systems that use sensors and receivers of sensor-recorded data, which is a factor to reduce the efficiency of the control system and even the instability of the structure. In this study, to investigate and compensate the effect of time delay in the hybrid vibration control system, an 11-story structure with a tuned mass damper and an MR damper was used by model algorithmic control (MAC) and nonlinear behavior of the structure in the control process. The linear and nonlinear structural models are created in OpenSEES, the control system in MATLAB; and the TCP/IP connection method was used to connect two programs. The fuzzy decision system is based on accelerating and decelerating movement. The structure has been subjected to seven earthquakes with maximum accelerations of 0.1 g to 1.0 g with an incremental step of 0.1 g. According to the results of incremental dynamic analysis, the average percentage of the fuzzy control system performance reduction, considering the time delay, is 15.28% and 38.57% for the maximum displacement and base shear in the linear structure, and 8.04% and 5.97% for the nonlinear structure, respectively. The assumed time delays have been effectively overcome using the model algorithmic control system (MAC), determining the prediction horizon of the structural behavior, and optimizing the control force in the control horizon. The performance of the MAC control system has been better than the fuzzy control system and the passive control with TMD. The average improvement percentage of the results of the maximum linear and nonlinear structural displacement response is respectively equal to 10.2 and 11.8 with the MAC control system, compared to the fuzzy control system without time delay. For the maximum base shear, it is equal to 8.32 and 2.49, respectively.

Analysis of the Control Characteristics of the Electro-Hydraulic Vibration System Based on the Single-Neuron Control Algorithm

This paper proposes an electro-hydraulic vibration control system based on the single-neuron PID algorithm, which improves the operating frequency of the electro-hydraulic fatigue testing machine and the control accuracy of the load force. Through mathematical modeling of the electro-hydraulic vibration system (EVS), a MATLAB/Simulink simulation, and experimental testing, this study systematically analyzes the output waveform of the EVS as well as the closed-loop situation of load force amplitude and offset under the action of the single-neuron PID algorithm. The results show that: the EVS with a 2D vibration valve as the core, which can control the movement of the spool in the two-degrees-of-freedom direction, can realize the output of an approximate sinusoidal load force waveform from 0 to 800 Hz. The system controlled by the single-neuron PID algorithm is less complex to operate than the traditional PID algorithm. It also has a short rise time for the output load force amplitude curve and a maximum control error of only 1.2%. Furthermore, it exhibits a rapid closed-loop response to the load force offset. The range variability of the load force is measured to be 1.43%. A new scheme for the design of EVS is provided in this study, which broadens the application range of electro-hydraulic fatigue testing machines.

A Study of Seating Suspension System Vibration Isolation Using a Hybrid Method of an Artificial Neural Network and Response Surface Modelling

A reliable prediction model can greatly contribute to the research of car seating system vibration control. The novelty of this paper lies in the development of a hybrid method of an artificial neural network (ANN) and response surface methodology (RSM) to predict the peak seat-to-head transmissibility ratio of a seating suspension system and to evaluate its ride comfort for different seat design parameters. Additionally, this method can remove the experimental design of the RSM model. In this paper, four seat design parameters are selected as input parameters and arranged using the central composite design method. The peak transmissibility ratio from seat to head at 4 Hz is chosen as the response target output value. To illustrate this hybrid method, the response target output value of the peak transmissibility ratio is calculated from the frequency response of a five-degrees-of-freedom (5-DOF) lumped-parameter biodynamic seating suspension model. The input design parameters and the response target output values are used to train an ANN to establish the relationship between the seat design parameters and the peak transmissibility ratio. At the same time, the input design parameters and the response target output values predicted by the ANN are used to develop the relationship between the seat design parameters and the peak transmissibility ratio using the response surface method and linear regression models. The hybrid of the ANN and response surface methods makes the planning or design of experiments not essential. The hybrid model of the ANN and response surface method is more accurate and convenient than a linear regression model for the study of seating system vibration isolation.

Seismic analyses of a five-story residential building supported by T-BAGS base isolation and vibration control system

Seismic analyses of a five-story residential building supported by T-BAGS base isolation and vibration control system

Comparison of single and multi-coil self-powered MR damper subjected to cyclic and earthquake loading for structural vibration control

A promising solution for semi-active vibration control of different dynamic systems is to use magnetorheological (MR) dampers. In the present study, the investigation focuses on developing a novel single and multi-coil self-powered magnetorheological (MR) damper system using electromagnetic induction (EMI) for seismic mitigation. The conventional MR dampers, which rely on external power sources, can be unreliable and impractical in earthquake-prone locations. Thus, the EMI device connected to the MR damper can be used as an effective and alternative power source for the MR damper, results in a self-powered system. The proposed energy-harvesting system is an MR damper placed above the top of the piston. The coil is wound around the piston, and the outer casing with a ferrite magnet is fixed. As the mechanical energy of the piston is converted into electrical energy, its self-tuning capacity is a perfect fit for structural vibration control applications. The MR damper is subjected to cyclic and time-history loading. At a maximum amplitude of 15 mm, the damper generated 1767.8 N for cyclic loading and -1780 N for earthquake loading, the El Centro earthquake 1940 is considered for the study. By placing EMI, the mechanical energy is converted into electrical energy and powers the damper to avoid external power. The experimental results showcase enhanced damping forces and adaptability, thereby establishing it as an innovative and effective it can be alternative to conventional MR dampers for vibration control in future

A performant PID autotuner based on a short relay test

Industrial applications encompass a wide range of fields, including chemical plants, biomedical engineering, vibration control, and mechanical systems, among others. Frequently, controller tuning is performed using a process model as a basis. Determining such a model can be a time-consuming and challenging task, requiring proper identification. Nonlinear processes often have a limited number of relevant operating points. Autotuning methods that collect pertinent process information at specific operating points and determine controller parameters automatically streamline the controller design process by eliminating the need for process modelling. This paper presents a novel relay based autotuning methodology for Proportional Integral Derivative (PID) controllers highly suitable for Industry 5.0 applications that is easily implemented. The methodology is successfully validated on two numerical examples consisting of a highly oscillatory process and a process with large time delay. Additionally, two experimental validations are presented for a mass-spring-damper system and a 2-tank process.

A FOPID based decentralised control system for vibration control of railway vehicle using hybrid optimisation

A FOPID based decentralised control system for vibration control of railway vehicle using hybrid optimisation

Implementation of an Active Vibration Control System on a Cogeneration Plant

Implementation of an Active Vibration Control System on a Cogeneration Plant

Vibration Training System Performance Test – Two Mass Absorber System Experiment

Two mass absorber is a vibration control system designed to enhance structural stability by strategically placing additional masses to effectively absorb and dampen vibrations. This technology mitigates resonance and harmful amplitude, reducing the risks of structural failure and operational inefficiencies in diverse engineering applications. Through this innovative approach, structures can withstand dynamic forces and operate efficiently in various fields. The TM 150 unit is used for conducting various experiments related to vibration phenomena. In this paper, experiments are carried out on a flexible beam that is oscillated using an unbalanced mass in the frequency range of 6 Hz to 18 Hz to see at which frequency the flexible beam will resonate. Another variation is to provide two mass absorbers under the flexible beam to see the difference. The experimental resonance graph was produced that was in accordance with the theoretical one, but with different amplitude units due to equipment limitations. The resulting graph shows before the absorber, the flexible beam resonates at its natural frequency. Afterward, small vibrations occur at that point, while resonance shifts. Furthermore, the performance of the vibration test unit is very good in showing the phenomena that occur in accordance with the theory.

Three-dimensional analysis of flow on vibration control system of building with fin configuration

Three-dimensional analysis of flow on vibration control system of building with fin configuration

Real-Time Integration of Identification and Semiactive Optimization Control for Mass Damper-Building Combined Systems under Known/Unknown Seismic Excitations

The integration of structural identification and vibration optimal control has been studied. Since the semiactive optimization vibrational control of civil structures needs to be implemented by massive control devices such as mass dampers, it is necessary to investigate the real-time integration of identification and semiactive optimization vibration control for mass damper-building combined systems. However, there is a lack of such studies in the literature. In this paper, a methodology is presented for real-time integration of identification and semiactive optimization vibration control of the mass damper-building combined system under known/unknown seismic excitations. For the combined system under known seismic excitations, the identification is implemented by the extended Kalman filter (EKF) using only partial structural acceleration responses. The identified structural state and parameters of mass damper-building systems are integrated in real time for the optimal control of systems by the linear-quadratic regulator (LQR) control algorithm and the Hrovat semiactive optimization control strategy via semiactive optimization mass dampers (SAMD). Then, it is extended to the scenario of unknown seismic excitations. The partially measured structural acceleration responses are absolute ones in this case, so the generalized extended Kalman filter with unknown input (GEKF-UI) developed by the authors is used to identify the structural input-state parameters of the mass dampers-building combined systems. The identification results are also integrated in real time for the semiactive optimization control of the combined system via SAMD. Two numerical simulation examples are used to test the proposed integration methods. It is shown that the proposed integration methods can reach almost the same optimal control effects as the conventional semiactive optimization control with known parameters of the mass damper-building combined systems under known/unknown seismic excitations.

Robust adaptive vibration control of a gantry crane system with flexible cable

SummaryIn this paper, a robust adaptive vibration control method for gantry crane system is proposed considering unknown parameters brought by unknown payload, cable length and tension. The control objective is to transport the cargo to the desired position while suppressing the vibration of the cable in the presence of unknown parameters. For this purpose, a boundary controller is designed with an adaptive law to compensate the parameter uncertainty of the system. The well‐posedness of the closed‐loop system is proved by means of operator semigroup theory and the asymptotic stability of the closed‐loop system is analyzed. Finally, the effectiveness of the proposed control approach is demonstrated through both numerical simulation comparisons and physical experiments.