Intrusive laser triangulation method for non-contact detection of voids in translucent composites

Bračun, Drago (author), Selak, Luka (author), Klobčar, Damjan (author), Katić, Marko (author), Markučić, Damir (author)

A non-contact optical inspection method for detecting voids in translucent composites is presented. Structured laser light is used to illuminate the inspected part. As the light penetrates the matrix, it scatters and is reflected from internal structures, rendering them perceptible in close proximity of the laser illumination. A systematic image acquisition and scanning approach is employed along with image processing to reconstruct and visually represent the internal composition of the inspected part. Experiments involving translucent epoxy and polyester based composites demonstrate capability to detect voids with depths reaching up to 5 mm. The detection depth is predominantly influenced by the light transmittance properties of the matrix, as well as the density and quantity of fiber layers. The arrangement of the camera and laser on the same side of the inspected part facilitates the examination of parts with varying thicknesses. The presented method is intended for automated inspection in mass production by leveraging its non-contact characteristics and high operational velocity.

• Language: English
• Keywords: resin transfer moulding, non-destructive testing, defects, optical properties, laser triangulation
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 9 str.
• Numbering: Vol. 145, art. 103143
• PID: 20.500.12556/RUL-158174
• UDC: 620.179.1:535
• ISSN on article: 0963-8695
• DOI: 10.1016/j.ndteint.2024.103143
• COBISS.SI-ID: 196899075
• Publication date in RUL: 28.05.2024

BRAČUN, Drago, SELAK, Luka, KLOBČAR, Damjan, KATIĆ, Marko and MARKUČIĆ, Damir, 2024, Intrusive laser triangulation method for non-contact detection of voids in translucent composites. NDT & E International [online]. 2024. Vol. 145,  103143. [Accessed 8 April 2025]. DOI 10.1016/j.ndteint.2024.103143. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=158174

Record is a part of a journal

• Title: NDT & E International
• Shortened title: NDT E int.
• Publisher: Elsevier
• ISSN: 0963-8695
• COBISS.SI-ID: 12515845

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: oblikovanje s prenosom smole, nedestruktivno testiranje, defekti, optične lastnosti, laserska triangulacija

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P2-0270
• Name: Proizvodni sistemi, laserske tehnologije in spajanje materialov