Experimental Measurement of Mode Shapes and Frequencies for Vibration of Plates by Optical Interferometry Method

Abstract

Most of the published literature for vibration mode shapes of plates is concerned with analytical and numerical results. There are only very few experimental results available for the full field configuration of mode shapes for vibrating plates. In this study, an optical system called the AF-ESPI method with the out-of-plane displacement measurement is employed to investigate experimentally the vibration behavior of square isotropic plates with different boundary conditions. The edges of the plates may either be clamped or free. As compared with the film recording and optical reconstruction procedures used for holographic interferometry, the interferometric fringes of AF-ESPI are produced instantly by a video recording system. Based on the fact that clear fringe patterns will appear only at resonant frequencies, both resonant frequencies and corresponding mode shapes can be obtained experimentally at the same time by the proposed AF-ESPI method. Excellent quality of the interferometric fringe patterns for the mode shapes is demonstrated.

Experimental Investigation of Vibrating Laminated Composite Plates by Optical Interferometry Method

“…Extensive experimental results of the resonant frequenciesand mode shape for isotropic plates with two different types of boundary conditions were obtained by Huang and Ma. 13 A digital speckle pattern interferometry technique was developed by Slangen et al 14 and was applied to study the resonant frequencies and mode shapes of a cantilever aluminum plate.…”

Full-Field Experimental Investigations on Resonant Vibration of Cracked Rectangular Cantilever Plates

“…A complete discussion of out-of-plane vibration mode shapes for different boundary conditions of isotropic plates without cracks was presented by Huang and Ma. 7 The vibrating mode shapes of the rst and the second modes shown in Figs. 3-5 are pure bending and torsion modes, respectively.The mode shapes for long cracks (Figs.…”

Continuous video stream pixel sensor: A CNN‐LSTM based deep learning approach for mode shape prediction

“…Non‐contact vibration measurement techniques attempt to address issues associated with contact‐type measurement techniques. Huang et al 23 put forward the optical system called the AF‐ESPI method, where the out‐of‐plane displacement estimation technique is employed to investigate the vibrational behavior of square‐shaped isotropic plates. Ruan et al 24 introduced a vibration displacement measurement system based on the photoelectric method, which consists of a laser source, a linear charge‐coupled device, and a corresponding software platform.…”