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dc.contributor.authorSmith, Jerome P.en
dc.date.accessioned2014-03-14T21:27:45Zen
dc.date.available2014-03-14T21:27:45Zen
dc.date.issued1993en
dc.identifier.otheretd-01242009-063336en
dc.identifier.urihttp://hdl.handle.net/10919/40754en
dc.description.abstractActive Structural Acoustic Control (ASAC) has been previously demonstrated for systems excited by single and multiple frequency disturbances. This work is an extension of ASAC techniques to the control of sound radiation from structures excited by a disturbance with broadband frequency content. An adaptive, multi-input multi-output (MIMO), feedforward broadband acoustic control system has been developed. The control approach is the least mean squares (LMS) algorithm. The compensators are adaptive finite impulse response (FIR) digital filters. The system identification of the control loop transfer functions were implemented with infinite impulse response (IIR) digital filters. The control inputs were implemented with piezoelectric ceramic actuators (PZT). Both far-field microphones and polyvinylidene fluoride (PVDF) structural sensors designed to optimally control the efficient acoustic radiating modes were used as error sensors. The disturbance was band-limited zero mean white noise and was input with a point force shaker. In the control of harmonically excited systems, satisfactory attenuation is possible with a single-input single-output (SISO) controller. In contrast, for Systems excited with broadband disturbances, a MIMO controller is necessary for significant acoustic attenuation. Experimental results for the control of two simplySupported plates are presented. Aspects addressed include the evaluation of the microphone and PVDF error sensors, optimization of sensors and actuators, FIR compensator size, controller sample rate, and convergence time. Thus this work provides a methodology for controlling broadband acoustic radiation from a structure with regard to the practical aspects of ASAC.en
dc.format.extentxiii, 145 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.isformatofOCLC# 29687285en
dc.relation.haspartLD5655.V855_1993.S647.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1993.S647en
dc.subject.lcshAcoustical engineeringen
dc.subject.lcshNoise controlen
dc.titleActive control of broadband acoustic radiation from structuresen
dc.typeThesisen
dc.contributor.departmentMechanical Engineeringen
dc.description.degreeMaster of Scienceen
thesis.degree.nameMaster of Scienceen
thesis.degree.levelmastersen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.disciplineMechanical Engineeringen
dc.type.dcmitypeTexten
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-01242009-063336/en
dc.date.sdate2009-01-24en
dc.date.rdate2009-01-24en
dc.date.adate2009-01-24en


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