Optical fibres contactless sensor for dynamic testing of lightweight structures

Issue title: The International Conference on Engineering Dynamics 2007

Article type: Research Article

Authors: Bregant, L. | Bressanutti, M.

Affiliations: Dipartimento Ingegneria Meccanica, Università di Trieste Via Valerio 10, 34127 Trieste, Italy | APE Research, Area Science Park Basovizza, Trieste, Italy

Note: [] Corresponding author. E-mail: [email protected]

Abstract: With dynamic testing, engineers describe activities focused on the identification of some properties of vibrating structures. This step requires for the measurements of excitations and responses signals, applying appropriate sensors directly on the test article. These instruments modify the system's mass and stiffness distributions and eventually the eigen-properties of the structure. These errors become unacceptable especially when testing lightweight structures. This paper shows the results of some tests performed on a small compressor with the purpose of identifying the blades' natural frequencies and modes. It compares the acquisitions performed with standard accelerometers and two different contact-less systems using as exciters either a micro-hammer or a micro inertial shaker. The paper shows how the contact-less sensors provide good quality data and consistent results in the mode identification phase.

Keywords: Contact-less sensors, dynamic testing, vibration, mass loading

Journal: Shock and Vibration, vol. 15, no. 3-4, pp. 413-424, 2008