An adaptive tuned mass damper based on the emulation of positive and negative stiffness with an MR damper

2010 ◽  
Vol 20 (1) ◽  
pp. 015012 ◽  
Author(s):  
F Weber ◽  
C Boston ◽  
M Maślanka
Keyword(s):  
Mr Damper ◽  
Tuned Mass Damper ◽  
Negative Stiffness ◽  
Mass Damper

scholarly journals NUMERICAL MODELLING OF MULTIPLE TUNED MASS DAMPER EQUIPPED WITH MAGNETO RHEOLOGICAL DAMPER FOR ATTENUATION OF BUILDING SEISMIC RESPONSES

2019 ◽  
Vol 81 (6) ◽  
Author(s):  
Afham Zulhusmi Ahmad ◽  
Aminudin Abu ◽  
Lee Kee Quen ◽  
Nor A’zizi Othman ◽  
Faridah Che In
Keyword(s):  
Damping Ratio ◽  
Time History ◽  
Mr Damper ◽  
Tuned Mass Damper ◽  
Response Analysis ◽  
Passive System ◽  
Value Analysis ◽  
Mass Damper ◽  
Magneto Rheological ◽  
Auxiliary Mass

The Tuned Mass Damper (TMD) is generally as a passive vibration control device consisting of added auxiliary mass with functioning spring and damping elements. TMD is basically designed to be tuned to the dominant frequency of a structure which the excitation of frequency will resonate the structural motion out of phase to reduce unwanted vibration. However, a single unit TMD is only capable of suppressing the fundamental structural mode. In order to control multimode vibrations and to cater wide band seismic frequency, more than one TMD is required to improve the effectiveness of a control mechanism. For the purpose of this study, a 3-storey benchmark reinforced structural building subjected to El Centro seismic ground motion is modelled as uncontrolled Primary Structure (PS) by considering appropriate structural properties such as stiffness and damping. Mathematical modelling of uncontrolled PS is developed and further evaluated numerically by assuming the PS as an equivalent lumped system. For the case of controlled PS which the passive mechanism is included to the system, optimum parameters of both TMD and Multiple TMD (MTMD) are designed to be tuned to the dedicated structural modes where the performance is dependent on specified parameters such as auxiliary mass ratio, optimum damping ratio, and optimum frequency ratio. The eigen value analysis is carried out by assuming that the structure is a linear time-invariant system. The input and output components of structural system arrangements are then characterized in the transfer function manner and then converted into state space function. To enhance structural control effectiveness, the adaptive system is incorporated by the attachment of Magneto-Rheological (MR) damper to both single TMD and MTMD passive system. The response analysis of the control system arrangements is executed using both time history and frequency response analysis. The main objectives of the design are to minimize both structural peak and Root Mean Square (RMS) displacements. From the analysis, the designed control mechanisms are concluded as highly effective in reducing all structural floor displacements for the semi-active cases with 99% displacement reduction for the third and second floors, and 98% for the first floor, compared to the uncontrolled case. It is concluded that the MR damper significantly contributed to the enhancement of the passive system to mitigate structural seismic vibration.

Vibration suppression of railway vehicles using a magneto-rheological fluid damper and semi-active virtual tuned mass damper control

2019 ◽  
Vol 67 (6) ◽  
pp. 493-507
Author(s):  
Ji-Hwan Shin ◽  
Jin-Ho Lee ◽  
Won-Hee You ◽  
Moon K. Kwak
Keyword(s):  
Control Algorithm ◽  
Mr Damper ◽  
Tuned Mass Damper ◽  
Railway Vehicle ◽  
Car Body ◽  
Fluid Damper ◽  
Mass Damper ◽  
Damper Control ◽  
Magneto Rheological ◽  
Mr Fluid Damper

A semi-active virtual tuned mass damper (SAVTMD) control algorithm is developed to suppress vibrations of a railway vehicle by using magneto-rheological (MR) damper. To this end, a virtual-tuned-mass-damper control algorithm analogous to the tuned mass damper was developed prior to the semi-active application. The proposed SAVTMD control algorithm uses the acceleration of the car body directly, so that it is more practical than the sky-hook control algorithm that uses the velocity of the car body. The application of the SAVTMD control to a real MR fluid damper is discussed, and a step-by-step procedure to calculate the command voltage to the driver of the MR fluid damper is presented. A hardwarein-the-loop simulation system developed in the previous study is used to test the SAVTMD control algorithm. The theoretical and experimental results showed that the proposed SAVTMD control algorithm is more effective than is the semi-active sky-hook control in suppressing vibrations of the car body of the railway vehicle by the MR damper.

Tuned mass damper and high static low dynamic stiffness isolator for vibration reduction of beam structure

2019 ◽  
Vol 234 (1) ◽  
pp. 95-115 ◽  
Author(s):  
Meysam Raei ◽  
Morteza Dardel
Keyword(s):  
Natural Frequency ◽  
Dynamic Stiffness ◽  
Excitation Amplitude ◽  
Tuned Mass Damper ◽  
Degree Of Freedom ◽  
Negative Stiffness ◽  
Low Frequencies ◽  
First Case ◽  
Mass Damper ◽  
Two Degree Of Freedom

In this work, the combination effect of tuned mass damper and high static low dynamic stiffness (HSLDS) isolator is investigated in reducing the vibration amplitude of Euler–Bernoulli beam with a nonlinear attachment. The performance of the absorber is studied in two cases; the first case, HSLDS isolator is one degree of freedom and the second case, two degree of freedom isolator is combined of HSLDS isolator and tuned mass damper absorber. By comparing the performance of these two isolators, it is revealed the two degree of freedom isolator has much better performance in direct force excitation and also improves the system performance in the base excitation. This isolator reduces the system amplitude at all frequencies, especially ultra-low frequencies, which is the main advantage to this isolator with respect to other isolators and reduces the natural frequency until the phenomenon of resonance occurs at a lower frequency. Moreover, decreasing the natural frequency increases the damping and in quasi zero stiffness and negative stiffness structure, the system has supercritical damping. This isolator is studied for positive, quasi zero and negative stiffness. The results show that the system with quasi zero stiffness has the best performances. Also, by increasing the excitation amplitude, the isolator loses its effectiveness.

Parameters optimization of series–parallel inerter system with negative stiffness in controlling a single–degree–of–freedom system under base excitation

2021 ◽  
pp. 107754632098533
Author(s):  
Marcial Baduidana ◽  
Xiaoran Wang ◽  
Aurelien Kenfack-Jiotsa
Keyword(s):  
Primary Structure ◽  
Vibration Amplitude ◽  
Tuned Mass Damper ◽  
Harmonic Excitation ◽  
Negative Stiffness ◽  
Base Excitation ◽  
Single Degree Of Freedom ◽  
White Noise Excitation ◽  
Single Degree ◽  
Mass Damper

This study proposes a series–parallel inerter system with negative stiffness for the passive vibration control of an undamped single–degree–of–freedom system under base excitation. The necessary and sufficient conditions for stability of series-parallel inerter system with negative stiffness are established by Routh–Hurwitz criterion, and the stability boundary is obtained. The tuning parameters of the series-parallel inerter system with negative stiffness are determined through fixed point theory, and a comparison between the vibration mitigation performance of series-parallel inerter system with negative stiffness, series–parallel inerter system (without negative stiffness), and tuned mass damper is presented considering both harmonic excitation, transient excitation, and random (white noise) excitation. The results of this study demonstrate that under base harmonic excitation, series-parallel inerter system with negative stiffness outperforms the series–parallel inerter system and tuned mass damper in terms of suppression bandwidth and reducing the peak vibration amplitude of the primary mass. In the case of base acceleration–excited primary structure, more than 49.84% and 67.53% improvement can be obtained from series-parallel inerter system with negative stiffness as compared with tuned mass damper in terms of suppression bandwidth and reducing the peak vibration amplitude, respectively. Whereas in the case of base displacement–excited primary structure, more than 78% and 80% improvement can be obtained from series-parallel inerter system with negative stiffness, respectively, following the same criteria. A slightly lower improvement has been obtained from series-parallel inerter system with negative stiffness as compared with series–parallel inerter system, which justified the superiority of series–parallel inerter system compared to tuned mass damper. The transient response investigation showed that series-parallel inerter system with negative stiffness outperforms the series–parallel inerter system and tuned mass damper in terms of much shorter stabilization times and lower peak amplitude of the primary mass. Finally, the further comparison among these devices (series-parallel inerter system with negative stiffness, series–parallel inerter system, and tuned mass damper) under white noise excitation also shows that series-parallel inerter system with negative stiffness is superior to series–parallel inerter system and tuned mass damper for a small inertance mass ratio. This result could provide a theoretical basis for the design of inerter-based isolators with negative stiffness.

Development of stiffness-adjustable tuned mass dampers for frequency retuning

2018 ◽  
Vol 22 (2) ◽  
pp. 473-485 ◽  
Author(s):  
Zhihao Wang ◽  
Hui Gao ◽  
Hao Wang ◽  
Zhengqing Chen
Keyword(s):  
Magnetic Force ◽  
Frequency Tuning ◽  
Equations Of Motion ◽  
Tuned Mass Damper ◽  
Significant Loss ◽  
Negative Stiffness ◽  
Experimental Investigations ◽  
Tuned Mass Dampers ◽  
Engineering Structures ◽  
Mass Damper

Tuned mass damper is an attractive strategy to mitigate the vibration of civil engineering structures. However, the performance of a tuned mass damper may show a significant loss due to the frequency detuning effect. Hence, an inerter-induced negative stiffness (apparent mass effect) and magnetic-force-induced positive/negative stiffness are proposed to integrate a stiffness-adjustable vertical tuned mass damper and pendulum tuned mass damper for frequency retuning, respectively. Based on the established differential equations of motion for a vertical tuned mass damper coupled with an inerter and a pendulum tuned mass damper integrated with a magnetic-force-induced positive-/negative-stiffness device, the frequency retuning principles of a vertical tuned mass damper and a pendulum tuned mass damper are, respectively, demonstrated. The frequency retuning strategies for both the vertical tuned mass damper and the pendulum tuned mass damper are confirmed and clarified by model tests. Furthermore, the performance of a retuned vertical tuned mass damper for mitigating vibration of a linear undamped single-degree-of-freedom primary structure is discussed, and the effects of the amplitudes of the pendulum tuned mass damper on magnetic-force-induced stiffness as well as the frequency of the pendulum tuned mass damper are also investigated. Both theoretical analysis and experimental investigations show that the proposed frequency tuning methodologies of tuned mass dampers are efficient and cost-effective with relatively simple configurations.

scholarly journals KDamping: A stiffness based vibration absorption concept

2016 ◽  
Vol 24 (3) ◽  
pp. 588-606 ◽  
Author(s):  
Ioannis A Antoniadis ◽  
Stratis A Kanarachos ◽  
Konstantinos Gryllias ◽  
Ioannis E Sapountzakis
Keyword(s):  
Vibration Isolation ◽  
Tuned Mass Damper ◽  
Negative Stiffness ◽  
Damping Properties ◽  
Frequency Range ◽  
Entire Frequency Range ◽  
Load Bearing Capacity ◽  
Vibration Absorption ◽  
Mass Damper ◽  
Elastic Forces

The KDamper is a novel passive vibration isolation and damping concept, based essentially on the optimal combination of appropriate stiffness elements, which include a negative stiffness element. The KDamper concept does not require any reduction in the overall structural stiffness, thus overcoming the corresponding inherent disadvantage of the “Quazi Zero Stiffness” (QZS) isolators, which require a drastic reduction of the structure load bearing capacity. Compared to the traditional Tuned Mass damper (TMD), the KDamper can achieve better isolation characteristics, without the need of additional heavy masses, as in the case of the T Tuned Mass damper. Contrary to the TMD and its variants, the KDamper substitutes the necessary high inertial forces of the added mass by the stiffness force of the negative stiffness element. Among others, this can provide comparative advantages in the very low frequency range. The paper proceeds to a systematic analytical approach for the optimal design and selection of the parameters of the KDamper, following exactly the classical approach used for the design of the Tuned Mass damper. It is thus theoretically proven that the KDamper can inherently offer far better isolation and damping properties than the Tuned Mass damper. Moreover, since the isolation and damping properties of the KDamper essentially result from the stiffness elements of the system, further technological advantages can emerge, in terms of weight, complexity and reliability. A simple vertical vibration isolation example is provided, implemented by a set of optimally combined conventional linear springs. The system is designed so that the system presents an adequate static load bearing capacity, whereas the Transfer Function of the system is below unity in the entire frequency range. Further insight is provided to the physical behavior of the system, indicating a proper phase difference between the positive and the negative stiffness elastic forces. This fact ensures that an adequate level of elastic forces exists throughout the entire frequency range, able to counteract the inertial and the external excitation forces, whereas the damping forces and the inertia forces of the additional mass remain minimal in the entire frequency range, including the natural frequencies. It should be mentioned that the approach presented does not simply refer to discrete vibration absorption device, but it consists a general vibration absorption concept, applicable also for the design of advanced materials or complex structures. Such a concept thus presents the potential for numerous implementations in a large variety of technological applications, whereas further potential may emerge in a multi-physics environment.

Prediction of Solutions of the Duffing System with Tuned Mass Damper

2020 ◽  
Vol 22 (4) ◽  
pp. 983-990
Author(s):  
Konrad Mnich
Keyword(s):  
Dynamical System ◽  
Duffing Oscillator ◽  
Probabilistic Approach ◽  
Nonlinear Dynamical System ◽  
Tuned Mass Damper ◽  
Nonlinear Dynamical ◽  
Duffing System ◽  
Mass Damper ◽  
Basin Stability ◽  
Stability Concept

AbstractIn this work we analyze the behavior of a nonlinear dynamical system using a probabilistic approach. We focus on the coexistence of solutions and we check how the changes in the parameters of excitation influence the dynamics of the system. For the demonstration we use the Duffing oscillator with the tuned mass absorber. We mention the numerous attractors present in such a system and describe how they were found with the method based on the basin stability concept.

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