Motion estimation from points without correspondences from orthographic projections

The authors present a novel algorithm for recovering motion parameters of the 3D point sets given point coordinates in three orthographic projections before and after motion. The algorithm requires no correspondences between two time instants and only a few correspondences in projections at the second time instant. The 3S scatter matrix of the 3D sets is calculated from 2D scatter matrices of projections. The algorithm uses matrix-eigendecomposition of the 3D scatter matrix to determine four candidate solutions for the rotation matrix