Comparative study of Line Scan and Flying Line Active IR Thermography operated with a 6-axis robot

In this paper, two Non Destructive Testing approaches by active infrared thermography mounted on a 6-axis robot are presented and studied. Data acquisition and thermal excitation is carried out dynamically over various CFRP specimens with increasing geometry complexity, from planar, to convex and concave shapes. An automated procedure is proposed to reconstruct thermal image sequences issued from the two scanning procedure studied: Line Scan and Flying Line procedures. Defective area detection is performed by image processing and an inverse technique based on thermal quadrupole method is used to map the depth of flaws. Results obtained are discussed and perspectives are addressed.

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