Displacement uncertainties with multiview correlation schemes

François Hild (1) , Stéphane Roux (1)

1 LMT - Laboratoire de Mécanique et Technologie

Multiview correlation is based on the use of explicitly parameterizing surfaces whose deformation is to be measured. In the present analyses, the surfaces are modeled as triangular facets (for local approaches), and with finite element meshes (for global approaches) using a linear interpolation between nodal displacements. Displacement uncertainty due to the presence of noise in the images is considered. The noise floor levels of the latter are compared for both local and global cases with two different sets of pictures. A priori estimates based upon the Hessian of the registration procedure are derived analytically, and a simplified expression is provided that is shown to be in very good agreement with their a posteriori evaluations. The uncertainty difference between local and global approaches is interpreted from their different spatial resolutions.

Mots clés: Uncertainty quantication; Covariance matrix; Noise floor level; Stereocorrelation

Domaines: Mécanique des matériaux [physics.class-ph]

François Hild, Stéphane Roux. Displacement uncertainties with multiview correlation schemes. Journal of Strain Analysis for Engineering Design, 2020, 55 (7-8), pp.199-211. ⟨10.1177/0309324720927102⟩. ⟨hal-02555887⟩