3D Scanning of specular and diffuse metallic surfaces using an infrared technique

Alban Bajard (1) , Olivier Aubreton (1) , Youssef Bokhabrine (1) , Benjamin Verney (1) , Gönen Eren (1) , Aytul Ercil (2) , Frederic Truchetet (1)

1 Le2i - Laboratoire Electronique, Informatique et Image [UMR6306]
2 VPA Laboratory

For the past two decades, the need for 3D Scanning of industrial objects has increased significantly. Therefore, many experimental techniques and commercial solutions have been proposed. However, difficulties remain for the acquisition of optically non-cooperative surfaces, such as transparent or specular surfaces. To address highly reflective metallic surfaces, we propose the extension of a technique that was originally dedicated to glass objects. In contrast to conventional active triangulation techniques that measure the reflection of visible radiation, we measure the thermal emission of a surface, which is locally heated by a laser source. Considering the thermophysical properties of metals, we present a simulation model of heat exchanges that are induced by the process, helping to demonstrate its feasibility on specular metallic surfaces and predicting the settings of the system. With our experimental device, we have validated the theoretical modeling and computed some 3D point clouds from specular surfaces of various geometries. Furthermore, a comparison of our results with those of a conventional system on specular and diffuse parts will highlight that the accuracy of the measurement no longer depends on the roughness of the surface.

Domaines: Vision par ordinateur et reconnaissance de formes [cs.CV]

Alban Bajard, Olivier Aubreton, Youssef Bokhabrine, Benjamin Verney, Gönen Eren, et al.. 3D Scanning of specular and diffuse metallic surfaces using an infrared technique. Optical Engineering, 2012, 51 (06), pp.0091-3286. ⟨hal-00690709⟩