Collaborative Exploration by Energy-Constrained Mobile Robots

  • Shantanu Das
  • Dariusz Dereniowski
  • Christina Karousatou
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9439)


We study the problem of exploration of a tree by mobile agents (robots) that have limited energy. The energy constraint bounds the number of edges that can be traversed by a single agent. Thus we need a team of agents to completely explore the tree and the objective is to minimize the size of this team. The agents start at a single node, the designated root of the tree and the height of the tree is bounded by the energy bound B. We provide an exploration algorithm without any knowledge about the tree and we compare our algorithm with the optimal offline algorithm that has complete knowledge of the tree. Our algorithm has a competitive ratio of O(logB), independent of the number of nodes in the tree. We also show that this is the best possible competitive ratio for exploration of unknown trees.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Shantanu Das
    • 1
  • Dariusz Dereniowski
    • 2
  • Christina Karousatou
    • 1
  1. 1.LIFAix-Marseille University and CNRSMarseilleFrance
  2. 2.Faculty of Electronics, Telecommunications and InformaticsGdańsk University of TechnologyGdańskPoland

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