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Showing 1 to 20 of 55 for “"Vibrometer"”.
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Digital frequency demodulation for a laser vibrometer
… a Michelson interferometer-based scanning laser vibrometer. The laser vibrometer is a velocity transducer that produces frequency-modulated signals that have traditionally been optically or electronically frequency shifted from baseband to an intermediate frequency. This shifting produces a …
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Misalignment Effects of the Self-Tracking Laser Doppler Vibrometer
There are many limitations to the current methods used to measure vibration on rotating structures. These limitations include physical flow blockages, relating the measurement spot to the structure rotation, data processing issues, and having to physically alter the engine. This work further …
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Structural energy and power flow using a scanning laser Doppler vibrometer
… consist of first using a scanning laser Doppler vibrometer (SLDV) to acquire spatially dense measurements of the structure's dynamic response. Second, the continuous 3-D complex-valued velocity field is solved from the laser data. Third, a spatially continuous model of the power is computed from …
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A Formulation for Updating Finite Element Models Through Consistent Use of Laser Vibrometer Data
… element(FE) models using scanning laser Doppler vibrometer(SLDV) dynamic response data. The update formulation is demonstrated in several computer simulations. The formulation is the result of incorporating an analytical FE model into an experimental model. The experimental model efficiently …
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Characterization of laser noise in free-free beam structures using a Scanning Laser Doppler Vibrometer
… dynamics is the use of a Scanning Laser Doppler Vibrometer (SLDV) to measure the dynamic response of vibrating structures. Essential in the optimal use of such a device is an understanding of the idiosyncrasies and operating parameters which may affect the quality of the experimental data. …
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The estimation and statistical inferences of the position and orientation of a scanning laser Doppler vibrometer
… and orientation) of the scanning laser Doppler vibrometer (SLDV) with respect to a structural coordinate system. The parameters in the forward model include the pose and the ranges. The parameters in the inverse model include the pose only. The parameters of those models are obtained by using …
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Reconstruction of 3-D structural dynamic response fields: an experimental, laser-based approach with statistical emphasis
… a set of 3-D projections based on Laser-Doppler-Vibrometer (LDV) localized instantaneous velocity measurements. Included along with an estimate of the 3-D velocity field, are its statistical characteristics and the inferential tools required to test the quality of the estimation. This …
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Development of the Velocity Transformation Function of Damped Flat Shell Finite Element for the Experimental Spatial Dynamics Modeling
… data obtained from a Scanning Laser Doppler Vibrometer (SLDV). In ESDM process, a finite element formulation is used to construct a numerical model of a structure. A conventional finite element such as rod, beam, or plate element, can be used to construct the numerical model of a structure …
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Three-dimensional velocity extraction using laser Doppler vibrometry
… be measured. Now with the use of a Laser Doppler Vibrometer the development of a method to measure three-dimensional velocities has provided the ability to measure in-plane velocities accurately. This thesis outlines the methods used for such three-dimensional extraction and gives an example of …
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Vibrations of high-speed dental handpieces measured using laser vibrometry
… conditions using a non-contact Scanning Laser Vibrometer (SLV). Methods: Five turbines (two KaVo, three W&H) and two speed-increasing handpieces (one KaVo and one W&H) were investigated using a Polytec SLV (PSV-300). Handpieces were operated under various conditions which included equipping …
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Vehicle Engine Classification Using of Laser Vibrometry Feature Extraction
… and remote sensor, the laser Doppler vibrometer (LDV) has been used in many different applications, such as inspection of aircrafts, bridge and structure and remote voice acquisition. However, using LDV as a vehicle surveillance device has not been feasible due to the lack of …
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Using a non-modal method for system identification of highly damped and high modal density mechanical structures
… recent development of the scanning laser Doppler vibrometer (SLDV) technology that provides efficient and massive dynamic data acquisition with high spatial density makes the new non-modal system identification techniques feasible. The proposed non-modal system identification method is based on …
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Effect of Vibration of Unconsolidated Sand on the Performance of Interferometric Vibration Sensors
… contact sensors are not desired. Laser Doppler vibrometers (LDV) and digital speckle pattern interferometers are studied in this thesis. The working principle of laser Doppler vibrometry and digital shearography is described. The effect of vibration of the unconsolidated sand on the performance …
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Detection of defects in FRP-reinforced concrete with the acoustic-laser vibrometry method
… system consisting of a commercial laser vibrometer system and conventional loudspeaker was used to perform tests with fabricated FRP-reinforced concrete specimens. The measurement results in the form of resonant frequencies were compared to those determined from theoretical and finite …
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An Experimental Evaluation of the Experimental Spatial Dynamics Modeling (ESDM) Technique
… such transducers is the scanning laser Doppler vibrometer (LDV). A scanning LDV can measure velocity at many structure locations. An important new technique, Experimental Spatial Dynamics Modeling (ESDM), utilizes such spatially dense velocity data. ESDM models continuous, three-dimensional …
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Radial-turbine mistuning
… to contribute to this failure mode. A laser vibrometer is used to characterize mistuning for a population of turbine wheels through the analysis of the blade-response to piezo-speaker induced noise. The turbine-wheel design under investigation is radial and is typically used in 6-12L diesel …
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A method for the spatial functionalization of the dynamic response of a structure with structural stability considerations
The scanning Laser Doppler Vibrometer (LDV) has developed into a useful tool for rapidly acquiring spatially dense structural dynamic response information in a noncontacting manner. The research presented in this paper is part of a larger project at the Structural Imaging and Modal Analysis …
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Active structural acoustic control smart panel with small scale proof mass actuators
… averaged vibration measured with a laser vibrometer and the reduction of the total sound power radiation measured in an anechoic room are presented.
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Vibration Extraction Using Rolling Shutter Cameras
… either direct contact with the object or a laser vibrometer. Although computer vision methods have been applied to solve this problem, high speed cameras are usually preferred. This study employs a consumer level rolling shutter camera for extracting main frequency components of small vibrations. …
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Remote nondestructive evaluation of composite-steel interface by acoustic laser vibrometry
… the target vibration is measured using a laser vibrometer. To study the acoustic laser method, a defect specimen was created from a plate of AL6XN stainless steel and a plate of glass FRP adhesively bonded on their faces with a purposely placed elliptical debonding defect. A number of parameters …
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