Dynamic Line Scan Thermography Optimisation Using Response Surfaces Implemented on PVC Flat Bottom Hole Plates

Abstract

Nowadays, performing dynamic line scan thermography (DLST) is very challenging, and therefore an expert is needed in order to predict the optimal set-up parameters. The parameters are mostly dependent on the material properties of the object to be inspected, but there are also correlations between the parameters themselves. The interrelationship is not always evident even for someone skilled in the art. Therefore, optimisation using response surface can give more insights in the interconnections between parameters, but also between the material properties and the variables. Performing inspections using an optimised parameter set will result in high contrast thermograms showing the size and shape of the defect accurately. Using response surfaces to predict the optimal parameter set enables to perform fast measurements without the need of extensive testing to find adequate measurement parameters. Differing from the optimal parameters will result in contrast loss or detail loss of the size and shape of the detected defect.

A Novel Line-Scan Algorithm for Unsynchronised Dynamic Measurements

“…Small defects may not be visible due to insufficient resolution. For example, in thermography, the rule of thumb is that the diameter of a defect must be at least the area of 3 × 3 pixels [22]. Dynamic line thermography (DLST) is often used when inspecting large surfaces or surfaces in a continuous process such as cold-rolled steel fabrication [22].…”

“…For example, in thermography, the rule of thumb is that the diameter of a defect must be at least the area of 3 × 3 pixels [22]. Dynamic line thermography (DLST) is often used when inspecting large surfaces or surfaces in a continuous process such as cold-rolled steel fabrication [22]. This technique uses a linear heat source and a thermal imaging camera at a specific distance from that heat source.…”

Infrared Imaging and NDT

“…The last paper of this special issue presents a methodology to optimize dynamic linescan thermography [13]. The authors of this work include Prof. Maldague, one of the most prolific and influential researchers in the field of infrared thermography.…”