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Active control of a flexible structure using a modal positive position feedback controllerThe feasibility of a new Modal Positive Position Feedback (MPPF) strategy in controlling the vibration of a complex flexible structure using a single piezo-electric active structural member is demonstrated. The control strategy generates its control forces by manipulating only the modal position signals of the structure to provide a damping action to undamped modes. This is in contrast to conventional modal controllers that rely in their operation on negative feedback of both the modal position and velocity. The proposed strategy is very simple to design and implement as it designs the controller at the uncoupled modal level and utilizes simple first order filters to achieve the Positive Position Feedback effect. The performance of the new strategy is enhanced by augmenting it with a time sharing strategy to share a small number of actuators between larger number of modes. The effectiveness of the new strategy is validated experimentally on a flexible box-type structure that has four bays and its first two bending modes are 2.015 and 6.535 Hz, respectively. A single piezo-electric actuator is utilized as an active structural member to control several transverse bending modes of the structure. The performance of the active control system is determined in the time and the frequency domains. The results are compared with those obtained when using the Independent Modal Space Control (IMSC) of Meirovitch. The experimental results suggest the potential of the proposed strategy as a viable means for controlling the vibration of large flexible structures in real time.
Document ID
19900063486
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Poh, S.
(Catholic Univ. of America Washington, DC, United States)
Baz, A.
(Catholic University of America, Washington, DC, United States)
Date Acquired
August 14, 2013
Publication Date
July 1, 1990
Publication Information
Publication: Journal of Intelligent Material Systems and Structures
Volume: 1
ISSN: 1045-389X
Subject Category
Cybernetics
Accession Number
90A50541
Funding Number(s)
CONTRACT_GRANT: NAG5-749
Distribution Limits
Public
Copyright
Other

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