Constant-Time Complete Visibility for Asynchronous Robots with Lights

  • Gokarna Sharma
  • Ramachandran Vaidyanathan
  • Jerry L. Trahan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10616)


We consider the distributed setting of N autonomous mobile robots that operate in Look-Compute-Move cycles and communicate with other robots using colored lights following the robots with lights model. We study the fundamental Complete Visibility problem of repositioning N autonomous robots on a plane so that each robot is visible to all others in this model. We assume obstructed visibility where a robot cannot see another robot if a third robot is positioned between them on the straight line connecting them. There exists an \(\mathcal{O}(\log N)\) time, \(\mathcal{O}(1)\) color algorithm for this problem in the asynchronous setting. In this paper, we provide the first, asymptotically optimal, \(\mathcal{O}(1)\) time, \(\mathcal{O}(1)\) color algorithm for this problem in the asynchronous setting. The proposed algorithm is collision-free – robots do not share positions and their paths do not cross. We also introduce a technique, called Beacon-Directed Curve Positioning, for moving robots in an asynchronous setting, that may be of independent interest.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Gokarna Sharma
    • 1
  • Ramachandran Vaidyanathan
    • 2
  • Jerry L. Trahan
    • 2
  1. 1.Department of Computer ScienceKent State UniversityKentUSA
  2. 2.School of Electrical Engineering and Computer ScienceLouisiana State UniversityBaton RougeUSA

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