Terrain Model Acquisition By Mobile Robot Teams and n-Connectivity
The connectivity of the configuration space has been a valuable concept in the motion planning for single robots in both known and unknown terrains. We show here that n-connectivity plays a similar role for mobile robot teams in providing algorithms for terrain model acquisition in unknown terrains. A bound on the connectivity degree of the free-space, reflected in that of a navigation course, provides us an estimate of the size of a robot team that is effective for the terrain. We consider an unknown planar polygonal terrain. The robots are point-sized and equipped with visual sensors which acquire all visible parts of the terrain by scan operations executed from their locations. The performance is measured by the number of sensor (scan) operations which are assumed to be the most time-consuming of all the robot operations. We show that the Voronoi diagrams and trapezoidal decomposition methods yield solutions for efficient terrain model acquisition by a 2- and 3-robot team using visual sensors.
KeywordsMobile Robot Voronoi Diagram Visibility Graph Single Robot Robot Team
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- 1.G. Chartrand and L. Lesniak. Graphs and Digraphs. Wadsworth and Brooks/Cole Advaced Books and Software, 1986.Google Scholar
- 2.H. Choset and J. Burdick. Sensor based motion planning: The hierarchical generalized Voronoi diagram. In Workshop on Algorithmic Foundations of Robotics. 1996.Google Scholar
- 3.G. Dudek, M. Jenkins, E. Milios, and D. Wilkes. Robust positioning with a multi-agent robotic system. In 1993 IJCAI Workshop Series: Dynamically Interacting Robots ,pages 118–123, 1993. Working Notes.Google Scholar
- 4.F. Harary. Graph Theory. Addison-Wesley Pub., 1969.Google Scholar
- 5.K. R. Harinarayan and V. J. Lumelsky. Sensor-based motion planning for multiple mobile robots in an uncertain environment. In Proceedings of IEEE/RSJ/GI Int. Conf. on Intelligent Robots and Systems ,pages 1485–1492, 1994.Google Scholar
- 6.K. Inoue, J. Ota, T. Hirano, D. Kurabayashi, and T. Arai. Iterative transportation by cooperative mobile robots in unknown environments. In Distributed Autonomous Robotic Systems 3 ,pages 2–12. Springer-Verlag, 1998.Google Scholar
- 7.K. Ishioka, K. Hiraki, and Y. Anzai. Cooperative map generation by heterogeneous autonomous mobile robots. In 1993 IJCAI Workshop Series: Dynamically Interacting Robots ,pages 57–67, 1993. Working Notes.Google Scholar
- 8.Y. Ishiwata, M. Inaba, and H. Inoue. Cooperative recognition of environments by multiple robots. In Proc. of JSME Annual Conf. on Robotics and Mechatronics ,pages 79–84, 1992.Google Scholar
- 15.N. S. V. Rao, S. Kareti, W. Shi, and S. S. Iyengar. Robot navigation in unknown terrains: An introductory survey of non-heuristic algorithms. Technical Report ORNL/TM-12410, Oak Ridge National Laboratory, Oak Ridge, TN, 1993.Google Scholar
- 17.N. S. V. Rao, N. Manickam, and V. Protopopescu. Cooperative terrain model acquisition by a team of two or three point-robots. In Proc. Int. Conf. on Robotics and Automation ,pages 1427–1433, 1996.Google Scholar