A System for Three-Dimensional Robotic Mapping of Underground Mines

We describe two robotic systems [6] for acquiring high-resolution volumetric maps of underground mines. Our systems have been deployed in an operational coal mine in Bruceton, Pennsylvania, where they have been used to generate interactive 3-D maps. Our approach includes a novel sensor head, assembled from multiple SICK laser range finders, and a real-time algorithm for scan matching that generates accurate volumetric maps. The scan matching algorithm performs horizontal and vertical simultaneous localization and mapping (SLAM). Data from the horizontal scans is used to remove artifacts in the vertical scans, and vice versa. The system can construct full 3-D volumetric maps hundreds of meters in diameter, even when no odometry information is available.