22 May 2018 Virtual projective shape matching in targetless CAD-based close-range photogrammetry for efficient estimation of specific deviations
Author Affiliations +
Abstract
A concept for targetless, computer-aided design (CAD)-based, close-range photogrammetry for online shape inspection is introduced. The shape of an object, which is arbitrarily located on a conveyor belt, is to be measured and compared with its nominal shape as defined by a CAD model. For most manufactured objects, deviations are only measured at a few given comparison points. These deviations can be estimated using local photogrammetry based on a priori geometrical information given by the CAD model and the comparison points. Our method results in faster output with higher precision, because we do not generate a shape representation of the entire measured object using typical photogrammetric methods. Images depicting the object from convergent angles are captured by an array of cameras in a precalibrated network, and the CAD model is matched and aligned, within the projective geometry of the camera network, to the depicted object in the images without the use of targets. An algorithm for solving this virtual projective targetless shape matching problem is presented.
© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
Per Bergström, Michael Fergusson, Mikael Sjödahl, "Virtual projective shape matching in targetless CAD-based close-range photogrammetry for efficient estimation of specific deviations," Optical Engineering 57(5), 053110 (22 May 2018). https://doi.org/10.1117/1.OE.57.5.053110 . Submission: Received: 16 February 2018; Accepted: 7 May 2018
Received: 16 February 2018; Accepted: 7 May 2018; Published: 22 May 2018
JOURNAL ARTICLE
11 PAGES


SHARE
Back to Top