[Tyler]

Localizing Outdoor Mobile Robots in the Absence of GPS
     

Many mobile robots rely on a combination of dead-reckoning and GPS for
outdoor navigation. Dead-reckoning is prone to inaccuracies and GPS
signals can vary and be lost altogether. What's a robot to do?
Traditional solutions have focused on localizing from overhead maps or
images, which works fine if the robot is a cruise missle but not so well
for ground robots. A tree in overhead images is big and green but a
ground robot sees a tree trunk. In a new paper, "Cost-based
Registration using A Priori Data for Mobile Robot Localization" (PDF
format) CMU researchers Ling Xu and Anthony Stentz present a
cost-based
algorithm that relies on kalman filters and particle filters to produce
position estimates. They've field-tested their algorithm on the
six-wheeled
Crusher robot with some success. See also our earlier article on
outdoor navigation research by Anthony Stentz.
   

http://robots.net/article/2447.html