A LOW-COST SYSTEM USING SPARSE VISION FOR NAVIGATION IN THE URBAN-ENVIRONMENT

Established mobility aids, such as the long cane, enable visually impa ired users to travel safely in urban environments. This paper describe s continuing work to enhance this mobility by providing a series of hi gh-level navigational goals. In particular, we describe algorithms to detect doorways and to facilitate centre-path travel. To maintain high performance at low cost, both algorithms use sparsely-sampled images from a single camera. Doorway detection is achieved by tile detection of characteristic patterns of near-vertical and near-horizontal lines. The direction of travel along a path is determined by locating the do minant vanishing point of the lines in the image. Experimental results are presented for both algorithms. (C) 1998 Elsevier Science B.V.