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Showing 1 to 12 of 12 for “"Piezoceramic Actuators"”.
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The effects of shaped piezoceramic actuators on the excitation of beams
The effect of the shape of piezoceramic actuators on the vibration response of a simply supported beam is investigated. An equation is derived to convert between the shape of the piezoceramic actuator and the resulting moment distribution caused on the structure. A beam simulation program is then …
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An experimental investigation of the harmonic excitation of simply supported plates with multiple surface-bonded piezoceramic actuators
… is performed experimentally using arrays of piezoceramic patch pair actuators bonded to the plate surface. The experimental techniques used are presented, and the effects of patch location, relative actuator phasing, and excitation frequency on modal excitation are demonstrated. In addition, …
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Enhancement of the Dynamic Buckling Load and Analysis of Active Constrained Layer Damping with Extension and Shear Mode Piezoceramic Actuators
… square plate sandwiched between two piezoceramic (PZT) layers. Points on the four edges of the bottom surface of the plate are restrained from moving vertically. The two opposite edges of the plate are loaded by equal in-plane compressive loads that increase linearly with time and the …
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Application of distributed measurements for finite element model verification
… by a distributed force (from a single or pair of piezoceramic actuators). The analytical results are obtained from the forced response analysis of a finite element model. A known piezoelectric actuator model that shows the actuation effects produced by symmetrically bonded actuators are line …
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Simultaneous active passive/control of extensional and flexural power flows in infinite thin beams
… flexural waves, using two co-located independent piezoceramic actuators bonded to the surface of the beam, is theoretically studied. The active control model shows that the use of two independent piezoceramic actuators allows complete cancellation of the total power flow (sum of the extensional …
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Power factor correction and power consumption characterization of piezoelectric actuators
A piezoceramic actuator used for structural control behaves electrically as a nearly pure capacitance. When conventional amplifiers are used to drive these actuators, the current and voltage is close to 90 degrees out of phase. This causes the power factor (PF) of the load to be close to zero and …
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Adaptive feedback technique for unmodeled disturbance rejection
… results are from a cantilever beam with piezoceramic actuators and sensors. The fixed feedback controller results are compared to the adaptive feedback control results. The comparison will include results from disturbances resulting from a single harmonic, narrowband signal, and broadband …
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Development of a compact sound source for the active control of turbofan inlet noise
… concept of a compact sound source driven by piezoactuators is experimentally investigated, and analytical design tools are developed. The sound source, consisting of a thin, cylindrically curved aluminum panel and a pair of collocated, surface-bonded piezoceramic actuators, was developed with the …
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Investigation of a compact acoustic source array for the active control of aircraft engine fan noise
… of a sinusoidally varying voltage to a piezoceramic actuator bonded to them. The finite element method was used as a design tool to size the panel based on desired vibration characteristics. A boundary element acoustic analysis was used to predict the acoustic output from various …
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Optimization of transducers for active structural acoustic control of complex structures using numerical techniques
… point force of 550 Hz and controlled by piezoceramic actuators. Although the excitation frequency is the same for each of the cases studied, the eigenproperties change with alteration of the physical parameters of the system. Therefore the excitation frequency for each case is effectively …
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Methodologies for active control of free shear flows
… a triangular jet is discussed in Chapter 2. The piezoceramic actuators were mounted on the flat sides of the nozzle. The flow was fully sheared near the nozzle. Single mode excitation with frequency as the varying parameter was found to be ineffective for controlling the far field evolution. In …
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Aerodynamic and Electromechanical Design, Modeling and Implementation Of Piezocomposite Airfoils
… authority. A challenge with piezoelectric actuators is that they require high voltage input; however the low power consumption allows for relatively lightweight electronic components. Another challenge, for piezoelectric actuated aerodynamic surfaces, is found in operating a relatively …