Building Globally Consistent Gridmaps from Topologies

T. Duckett and A. Saffiotti

This paper addresses the problem of recovering metric consistency in a global gridmap for mobile robot navigation. Gridmaps can only be updated consistently using exact estimates of the robot position, a requirement which is very hard to fulfil in real world environments because the same sensor data must be used for both map building and self-localisation. To overcome this problem, we use a hierarchy of robot maps which integrates topological and grid-based representations. The consistency problem is solved at the topological level, by applying a relaxation technique to generate coordinates for the places in the robot's map. Consequently, the robot is able to recover a globally consistent gridmap without requiring accurate sensors or high computational costs. Experiments on a Nomad 200 robot are presented which demonstrate the efficacy of our approach.
T. Duckett and A. Saffiotti. Building Globally Consistent Gridmaps from Topologies. Proc. of the 6th Int. IFAC Symp. on Robot Control (SYROCO) pp. 357-361. Wien, Austria, 2000.
BibTeX entry
Email Tom Duckett
Email Alessandro Saffiotti
Availability (©)
PS PostScript file (1.6 Mb)
Compressed PostScript file (457 Kb)
PDF PDF file (914 Kb)
Page hosted by  AASS Designed and maintained by Alessandro Saffiotti