Patrick Pfaff, Rudolph Triebel, and Wolfram Burgard
An Efficient Extension to Elevation Maps for Outdoor Terrain
Mapping and Loop Closing
abstract:
Elevation maps are a popular data structure for representing the
environment of a mobile robot operating outdoors or on not-flat
surfaces. Elevation maps store in each cell of a discrete grid the
height of the surface at the corresponding place in the environment.
The use of this 2 1/2 - dimensional representation, however,
is disadvantageous when utilized for mapping with mobile robots
operating on the ground, since vertical or overhanging objects
cannot be represented appropriately. Furthermore, such objects can
lead to registration errors when two elevation maps have to be
matched. In this paper, we propose an approach that allows a mobile
robot to deal with vertical and overhanging objects in elevation
maps. Our approach classifies the points in the environment
according to whether they correspond to such objects or not. We
also present a variant of the ICP algorithm that utilizes the
classification of cells during the data association. Additionally,
we describe how the constraints computed by the ICP algorithm can be
applied to determine globally consistent alignments. Experiments
carried out with a real robot in an outdoor environment demonstrate
that our approach yields highly accurate elevation maps even in the
case of loops. We furthermore present experimental results
demonstrating that our classification increases the robustness of
the scan matching process.
Bibtex:
@InProceedings{pfaff06euros,
AUTHOR = {Pfaff, P. , Triebel R., and Burgard, W.},
TITLE = {An Efficient Extension to Elevation Maps for Outdoor Terrain
Mapping and Loop Closing},
BOOKTITLE = International Journal of Robotics Research (IJRR) - Special Issue of International Conference on Field and Service Robotics (FSR),
YEAR = 2005,
NOTE = "To appear"
}
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