A mobile robot iconic position estimator using a radial laser scanner

Position determination for a mobile robot is an important part of autonomous navigation. In many cases, dead reckoning is insufficient because it leads to large inaccuracies over time. Beacon- and landmark-based estimators require the emplacement of beacons and the presence of natural or man-made structure respectively in the environment. In this paper, we present a new algorithm for efficiently computing accurate position estimates based on a radially-scanning laser rangefinder that does not require structure in the environment. The algorithm employs a connected set of short line segments to approximate the shape of any environment and can easily be constructed by the rangefinder itself. We describe techniques for efficiently managing the environment map, matching the sensor data to the map, and computing the robot's position. We present accuracy and runtime results for our implementation.A portion of this paper was presented at the IEEE Int. Conference on Robotics and Automation, Nice, France, May 1992.This work was carried out during the stay of the first and third authors in the Field Robotics Center, The Robotics Institute, Carnegie Mellon University, under grant of the Spanish Government. The research was sponsored in part by the United States Bureau of Mines, contract No. 358021.