The Experimental Study by Electronic Speckle Pattern Interferometry of Resonant Frequencies and Mode Shapes for Square Laminate Plates with Rounded Corners and Chamfers

Electronic speckle pattern interferometry (ESPI) was used for tuning and visualization of natural frequencies of a square laminate plate with rounded corners and chamfers. The plate was excited to resonant vibration by a sinusoidal acoustical source, which provided a continuous range of audio frequencies. Numerical calculations of resonant frequencies and mode shapes based on a finite element package are also performed and good agreements are obtained if compared with experimental measurements. The influence of shaped of corners, which include rounded corners and chamfers, on the vibration analysis of square plates is discussed in detail. It is interesting to note that the mode number sequences for some resonant modes are changed. The transition of mode shapes from the square plate to the circular plate is also discussed.