Extracting topographic features for outdoor mobile robots

Methods are presented for building high-level terrain descriptions, referred as topographic maps, by extracting terrain features like peaks, pits, ridges, and ravines from the contour map. The resulting topographic map contains the location and type of terrain features as well as the ground topography. The authors develop new definitions for those topographic features based on the contour map. They build a contour map from an elevation map and generate the connectivity tree of all regions separated by the contours. The authors use this connectivity tree, called a topographic change tree, to extract the topographic features. Experimental results on a digital elevation model support the definitions for topographic features and the approach