B34 Self-Sensing and Model-Free Vibration Control Based on LQG Strategy

This paper investigates the dynamic analysis of a single-rotor shaft system with nonlinear elastic bearings at the ends mounted on viscoelastic suspension. A Timoshenko shaft model is utilized to incorporate the flexibility of the shaft; the rotor is considered to be rigid and located at the mid-span of the shaft. A nonlinear bearing pedestal model is assumed which has a cubic nonlinear spring and linear damping characteristics. The viscoelastic supports are modeled using the Kelvin-Voigt model. Free vibration is investigated based on the direct multiple scales method of one-to-one frequency-to-amplitude relationship using third order perturbation expansion. The results of the nonlinear analysis show that a limiting value of the internal damping coefficient of the shaft exists where the trend of the frequency-response curve switches.

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Effectiveness of Active TMD for Buildings’ Control

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-1984-0027 ◽

1984 ◽

Vol 8 (4) ◽

pp. 179-184 ◽

Cited By ~ 8

Author(s):

M. Abdel-Rohman

Keyword(s):

Free Vibration ◽

Vibration Control ◽

Forced Vibration ◽

Free Vibrations ◽

Tuned Mass Dampers ◽

Numerical Investigations

This paper presents some numerical investigations obtained from studying the effectiveness of active tuned mass dampers (TMD) in suppressing the vibrations in buildings. The results of the study indicate that active TMDs are not effective for forced vibration control in buildings. However, active TMDs are very effective and economic in suppressing the free vibrations response. For typical wind excitation, it is thus recommended to use passive TMD for forced vibration control, and active TMD for free vibration control.

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Free vibration control of smart composite beams using particle swarm optimized self-tuning fuzzy logic controller

Journal of Sound and Vibration ◽

10.1016/j.jsv.2014.06.001 ◽

2014 ◽

Vol 333 (21) ◽

pp. 5244-5268 ◽

Cited By ~ 24

Author(s):

Nemanja D. Zorić ◽

Aleksandar M. Simonović ◽

Zoran S. Mitrović ◽

Slobodan N. Stupar ◽

Aleksandar M. Obradović ◽

...

Keyword(s):

Fuzzy Logic ◽

Free Vibration ◽

Vibration Control ◽

Fuzzy Logic Controller ◽

Particle Swarm ◽

Composite Beams ◽

Smart Composite ◽

Self Tuning

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Vibration Control in Turning Machining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.706-708.1672 ◽

2013 ◽

Vol 706-708 ◽

pp. 1672-1675 ◽

Cited By ~ 1

Author(s):

Long Bo Chen ◽

Ji Lin Guo ◽

Tian Rui Zhou ◽

Tao Jiang

Keyword(s):

Free Vibration ◽

Machine Tool ◽

Vibration Control ◽

Detailed Analysis ◽

Forced Vibration ◽

Cutting Tool ◽

System Dynamic ◽

Cutting Process ◽

Excited Vibration ◽

Process System

Vibration in turning processing is associated with free vibration, forced vibration and self-excited vibration, the composition and machine tool, tool and workpiece process system dynamic characteristic.A detailed analysis of the main types of vibration in turning and the causes, and put forward from the aspects of cutting tool, fixture, cutting process, reduce or eliminate vibration measures.

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Free Vibration Control of MRE Embedded Viscoelastic Cored Sandwich Beam With Time Varying Magnetic Field

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 5 ◽

10.1115/esda2010-24613 ◽

2010 ◽

Cited By ~ 1

Author(s):

Biswajit Nayak ◽

Santosha K. Dwivedy ◽

K. S. R. Krishna Murthy

Keyword(s):

Magnetic Field ◽

Free Vibration ◽

Vibration Control ◽

Multiple Scales ◽

Sandwich Beam ◽

Beam Theory ◽

Critical Parameters ◽

Time Varying ◽

Iron Particles ◽

System Method

The present work deals with the free vibration control of a simply supported and cantilevered sandwich beam with magnetorheological elastomer (MRE) embedded viscoelastic core and conductive skins subjected to time varying magnetic field. The skins of the sandwich beam are conductive such that magnetic loads are applied to the skins. Considering the core to be stiff in transverse direction, classical sandwich beam theory has been used along with extended Hamilton’s principle and Galarkin’s method to derive the governing equation of motion. The resulting equation reduces to that of a parametrically excited system. Method of multiple scales has been used to study the response and stability of the system. Critical parameters of amplitude and frequency of magnetic field have been determined to actively control the free vibration response of the system. Effects of percentage of iron particles and carbon black in attenuation of vibration of the sandwich beam have been studied. Here the experimentally obtained properties of recently developed magnetorheological elastomers based on natural rubber containing iron particles and carbon blacks have been considered in the numerical simulation.

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