Structure from Constrained Motion Using Point Correspondences

T. N. Tan, G. D. Sullivan and K. D. Baker

Department of Computer Science,

University of Reading, RG6 6AY, UK



Mobile objects are frequently confined to move on a ground surface which, locally at least, is approximately flat. Existing structure-from-motion (SFM) algorithms make no use of real-world motion constraints of this kind. In this paper we present a simple novel SFM algorithm whereby the above motion constraints can be conveniently incorporated into the constraint equations on the relative depths of rigid points. The simplicity and homogeneity of the constraint equations allow simple and robust direct solutions of the relative depths. The proposed algorithm is non-iterative, and in general requires a minimum of three points in two frames. It is superior to general linear SFM algorithms not only in computational cost but also in accuracy and noise robustness..

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Last Modified: 10:57am GMT, February 26, 1998