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Title: A novel imaging technique for measuring kinematics of light-weight flexible structures

Abstract

A new imaging algorithm is proposed to capture the kinematics of flexible, thin, light structures including frequencies and motion amplitudes for real time analysis. The studied case is a thin flexible beam that is preset at different angles of attack in a wind tunnel. As the angle of attack is increased beyond a critical value, the beam was observed to undergo a static deflection that is ensued by limit cycle oscillations. Imaging analysis of the beam vibrations shows that the motion consists of a superposition of the bending and torsion modes. The proposed algorithm was able to capture the oscillation amplitudes as well as the frequencies of both bending and torsion modes. The analysis results are validated through comparison with measurements from a piezoelectric sensor that is attached to the beam at its root.

Authors:
 [1];  [2];  [3];  [4]
  1. Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA and Department of Aerospace Engineering, Military Technical College, Cairo 11241 (Egypt)
  2. Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627 (United States)
  3. Department of Aerospace and Ocean Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)
  4. Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)
Publication Date:
OSTI Identifier:
22597840
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALGORITHMS; AMPLITUDES; BEAMS; BENDING; CAPTURE; COMPARATIVE EVALUATIONS; IMAGES; LIMIT CYCLE; PIEZOELECTRICITY; REAL TIME SYSTEMS; SENSORS; WIND TUNNELS

Citation Formats

Zakaria, Mohamed Y., E-mail: zakaria@vt.edu, Eliethy, Ahmed S., Canfield, Robert A., and Hajj, Muhammad R. A novel imaging technique for measuring kinematics of light-weight flexible structures. United States: N. p., 2016. Web. doi:10.1063/1.4955442.
Zakaria, Mohamed Y., E-mail: zakaria@vt.edu, Eliethy, Ahmed S., Canfield, Robert A., & Hajj, Muhammad R. A novel imaging technique for measuring kinematics of light-weight flexible structures. United States. doi:10.1063/1.4955442.
Zakaria, Mohamed Y., E-mail: zakaria@vt.edu, Eliethy, Ahmed S., Canfield, Robert A., and Hajj, Muhammad R. Fri . "A novel imaging technique for measuring kinematics of light-weight flexible structures". United States. doi:10.1063/1.4955442.
@article{osti_22597840,
title = {A novel imaging technique for measuring kinematics of light-weight flexible structures},
author = {Zakaria, Mohamed Y., E-mail: zakaria@vt.edu and Eliethy, Ahmed S. and Canfield, Robert A. and Hajj, Muhammad R.},
abstractNote = {A new imaging algorithm is proposed to capture the kinematics of flexible, thin, light structures including frequencies and motion amplitudes for real time analysis. The studied case is a thin flexible beam that is preset at different angles of attack in a wind tunnel. As the angle of attack is increased beyond a critical value, the beam was observed to undergo a static deflection that is ensued by limit cycle oscillations. Imaging analysis of the beam vibrations shows that the motion consists of a superposition of the bending and torsion modes. The proposed algorithm was able to capture the oscillation amplitudes as well as the frequencies of both bending and torsion modes. The analysis results are validated through comparison with measurements from a piezoelectric sensor that is attached to the beam at its root.},
doi = {10.1063/1.4955442},
journal = {Review of Scientific Instruments},
number = 7,
volume = 87,
place = {United States},
year = {Fri Jul 15 00:00:00 EDT 2016},
month = {Fri Jul 15 00:00:00 EDT 2016}
}
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