Finite Element based sequential Bayesian Non-Rigid Structure from Motion

Navier’s equations modelling linear elastic solid deformations are embedded within an Extended Kalman Filter (EKF) to compute a sequential Bayesian estimate for the Non-Rigid Structure from Motion problem. The algorithm processes every single frame of a sequence gathered with a full perspective camera. No prior data association is assumed because matches are computed within the EKF prediction-match-update cycle. Scene is coded as a Finite Element Method (FEM) elastic thin-plate solid, where the discretization nodes are the sparse set of scene points salient in the image. It is assumed a set of Gaussian forces acting on solid nodes to cause scene deformation. The EKF combines in a feedback loop an approximate FEM model and the frame rate measurements from the camera, resulting in an efficient method to embed Navier’s equations without resorting to expensive non-linear FEM models. Classical FEM modelling has implied an interactive identification of boundary points to constrain the...

• Type: Journal
• Year: 2012
• Where: CVPR
• Authors: Antonio Agudo, Begoña Calvo, J. M. M. Montiel
• Keywords: Computer Vision, Cvpr 2012, Extended Kalman Filter, Finite Element Method, Stiffness Matrix