Technique for compensating excessive rigid body motion in nondestructive testing of large structures using shearography

Obtaining four-dimensional vibration information for vibrating surfaces with a Kinect sensor

“…Further discussions of holographic interferometry were presented in many references [9][10][11]. Shearography has been shown to be more resilient to rigid body motion than ESPI or holographic interferometry and may be better suited for industrial applications [12], such as the production and development in the areas of aerospace, wind rotor blades, automation and materials research. But the holographic interferometry and shearography share the weakness of directly providing only relative displacements and describing obtained vibration data with one dimension only.…”

“…(12) can be obtained by the Matlab Curve Fitting Tool, and then the parameters in Eq. (11) are all determined by the following equations:…”

3D digital image correlation methods for full-field vibration measurement

“…In addition to stationary testing, ESPI using a pulsed-laser source can measure in-plane heat-and centrifugally-induced displacements of components rotating with tangential velocities up to 300 ms À 1 [16]. For rotating structures, shearography has been shown to be more resilient to rigid body motion than ESPI or holographic interferometry and may be better suited for industrial applications [17,18]. A drawback for the optical techniques mentioned is that they only directly provide relative displacements and are limited to measurement along a single axis.…”

Measurements of Electron Drift Velocity in 3He Gas

“…The technique is similar to electronic speckle pattern interferometry (ESPI), but has a considerable advantage in that it is inherently more resilient to relative movement between the test object and optical instrument and is therefore more suitable for use in industrial environments [4].…”