Asynchronous Gathering in Rings with 4 Robots

  • François BonnetEmail author
  • Maria Potop-Butucaru
  • Sebastien Tixeuil
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9724)


In this paper we consider the gathering of oblivious mobile robots in a n-node ring. In this context, the single class of configurations left open in the most recent study [2] is \(\mathcal {SP}4\) (a special class of configurations with only four robots).

We present an algorithm to solve some of the most intricate configurations in \(\mathcal {SP}4\), those that can lead to a change of the axis of symmetry. Our approach lays the methodological bases for closing the remaining open cases for \(\mathcal {SP}4\) solvability.



This work was supported in part by LINCS and by JSPS KAKENHI Grant Number 26870228. The authors would like to thank the anonymous reviewers for their constructive comments.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • François Bonnet
    • 1
    Email author
  • Maria Potop-Butucaru
    • 2
    • 3
  • Sebastien Tixeuil
    • 2
    • 3
    • 4
  1. 1.Graduate School of Advanced Science and TechnologyJAISTNomiJapan
  2. 2.UPMC Sorbonne Universités, LIP6-CNRSParisFrance
  3. 3.CNRS, LIP6-CNRSParisFrance
  4. 4.Institut Universitaire de FranceParisFrance

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