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Showing 1 to 20 of 22 for “"Active Structural Acoustic Control"”.
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Advanced sensing techniques for active structural acoustic control
… required in achieving adaptive structures for active structural acoustic control (ASAC). Test structures studied in this work included a baffled simply supported beam and a baffled simply supported plate which were subjected to a harmonic input disturbance created physically with a shaker and …
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Demonstration of active structural acoustic control of cylinders
Active control is applied to reduce noise emission from a vibrating elastic cylinder by exerting forces on the cylinder that cancel the noise-generating vibration. This technique is called Active Structural Acoustic Control (ASAC) (Fuller, 1987). Sensors are implemented using piezoelectric film, …
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Advanced Time Domain Sensing For Active Structural Acoustic Control
Active control of sound radiation from vibrating structures has been an area of much research in the past decade. In Active Structural Acoustic Control (ASAC), the minimization of sound radiation is achieved by modifying the response of the structure through structural inputs rather than by …
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Active structural acoustic control smart panel with small scale proof mass actuators
… a comprehensive study of decentralised feedback control on a smart panel with electrodynamic proof mass actuators and velocity sensors at their footprints. The aim is to provide guidance for the design of light, simple, robust and low cost, control units which can be attached in large numbers to …
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Active structural acoustic control of double panel systems including hierarchical control approaches
The general trends and principles of active structural acoustic control when applied to double panel systems are investigated to determine the respective advantages and limitations of this approach. Included is the application of a novel hierarchical control approach which may reduce the controller …
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On the use of modern control theory for active structural acoustic control
A modern control theory formulation of Active Structural Acoustic Control (ASAC) of simple structures radiating acoustic energy into light or heavy fluid mediums is discussed in this dissertation. ASAC of a baffled, simply-supported plate subject to mechanical disturbances is investigated. For the …
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System Identification and Optimization Methodologies for Active Structural Acoustic Control of Aircraft Cabin Noise
There has been much recent research on the control of complex sound fields in enclosed vibrating structures via active control techniques. Active Structural Acoustic Control (ASAC) has shown much promise for reducing interior cabin noise in aircraft by applying control forces directly to the …
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Optimization of transducers for active structural acoustic control of complex structures using numerical techniques
A general procedure for the optimization of control actuator forces and locations to minimize the total radiated sound power from complex structures has been developed. This optimization procedure interfaces finite and boundary element models with non-linear optimization techniques. The …
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Active structural acoustic control of aircraft interior flow noise via the use of active trim panels
… over the crown of the aircraft. The noise control approach is to mount piezoelectric actuators to the aircraft interior cockpit crown trim panel and use them to actively control aircraft interior noise with feed-forward adaptive LMS control algorithms. The experiments were performed on a …
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Structural-acoustic design and control of an integrally actuated composite panel
The need for structural based acoustic control is evident in aircraft, aerospace, and naval systems. A promising approach utilizes active materials to intelligently control the dynamic response of light-weight, modally dense structures suppressing the radiated acoustic power. The basic …
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The optimal design of transducers for active control of multiple-frequency structural sound radiation
This study is concerned with the problem of active structural acoustic control (ASAC) of radiation from elastically supported plates under multiple-frequency excitation. The control is achieved by use of piezoelectric (PZT) actuators. An optimization procedure is developed to find the optimal …
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MODELING AND DESIGN OF A SMART DOUBLE-PANEL SYSTEM FOR THE CONTROL OF SOUND TRANSMISSION INTO AIRCRAFT CABIN
… panel of an aircraft is subjected to incident acoustic waves with a broad range of frequencies. When the incident acoustic waves transmit through the airborne and structure-borne sound paths of the aircraft double-panel structure, sound energies with mid-range and high-range frequencies are …
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Active control of a coupled plate-cylinder system
… cylindrical shell via a fixed number of active-passive mounts. A harmonic point-force disturbance is applied to the plate. Various active control approaches are applied to minimize the acoustic pressure radiated by the coupled system. The Active Structural Acoustic Control (ASAC) …
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Active control of broadband acoustic radiation from structures
Active 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 …
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Optimum design for feedforward structural-acoustic control of complex structural systems
An efficient design formulation for feedforward Active Structural Acoustic Control (ASAC) systems for complex structures and disturbances is presented. The approach consists in a multi-level optimization procedure. The upper level part is carried out in the modal domain, where the optimum modal …
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Decentralized control of sound radiation from periodically stiffened panels
Active structural acoustic control has previously been used to reduce low-frequency sound radiation from relatively simple laboratory structures. However, significant implementation issues have to be addressed before active control can be used on large, complex structures such as an aircraft …
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Design of Active Structure Acoustic Control Systems Using Eigenassignment Approach
Active structural acoustic control (ASAC) in conjunction with the adaptive feedforward control has been proved to be an efficient practical approach to reduce structure-borne sound. ASAC works on the principles of reducing the vibration amplitude of the structure (modal reduction), as well as …
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Optimum Actuator Grouping in Feedforward Active Control Applications
… benefit of grouping actuators to increase the controllability of an active control system, without increasing the number of control channels. By driving two or more secondary sources with the same control input, one is also able to reduce the hardware cost and complexity. In this work, a time …
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Active control of automobile cabin noise with conventional and advanced speakers
Recently much research has focused on the control of enclosed sound fields, particularly in automobiles. Both Active Noise Control (ANC) and Active Structural Acoustic Control (ASAC) techniques are being applied to problems stemming from power train noise and road noise (noise due to the …
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A regression-based approach for simulating feedfoward active noise control, with application to fluid-structure interaction problems
… numerical tools for simulating feedforward active noise control in the frequency domain. Feedforward control is numerically similar to linear least squares regression, and can take advantage of various numerical techniques developed in the statistics literature for use with regression. …
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