Lab Meeting March 9th (Andi): Multilevel Surface Maps

An Efficient Extension to Elevation Maps for Outdoor Terrain Mapping and Loop Closing
Authors: Patrick Pfaff, Rudolph Triebel and Wolfram Burgard

and

Monte Carlo Localization in Outdoor Terrains Using Multilevel Surface Maps
Authors: Rainer Kuemmerle, Patrick Pfaff, Rudolph Triebel and Wolfram Burgard

Abstract: We propose a novel combination of techniques for robustly estimating the position of a mobile robot in outdoor environments using range data. Our approach applies a particle filter to estimate the full six-dimensional state of the robot and utilizes multilevel surface maps, which, in contrast to standard elevation maps, allow the robot to represent vertical structures and multiple levels in the environment. We describe probabilistic motion and sensor models to calculate the proposal distribution and to evaluate the likelihood of observations. We furthermore describe an active localization approach that actively selects the sensor orientation of the two-dimensional laser range scanner to improve the localization results. To efficiently calculate the appropriate orientation, we apply a clustering operation on the particles and evaluate potential orientations on the basis of these clusters.
Experimental results obtained with a mobile robot in large-scale outdoor environments indicate that our approach yields robust and accurate position estimates. The experiments also demonstrate that multilevel surface maps lead to a significantly better localization performance than standard elevation maps. They additionally show that further accuracy is obtained from the active sensing approach.

Links:
paper1
paper2