Fault-Induced Dynamics of Oblivious Robots on a Line

  • Jean-Lou De CarufelEmail author
  • Paola Flocchini
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10616)


The study of computing in presence of faulty robots in the Look-Compute-Move model has been the object of extensive investigation, typically with the goal of designing algorithms tolerant to as many faults as possible. In this paper, we initiate a new line of investigation on the presence of faults, focusing on a rather different issue. We are interested in understanding the dynamics of a group of robots when they execute an algorithm designed for a fault-free environment, in presence of some undetectable crashed robots. We start this investigation focusing on the classic point-convergence algorithm by Ando et al. [2] for robots with limited visibility, in a simple setting (which already presents serious challenges): the robots operate fully synchronously on a line, and at most two of them are faulty. Interestingly, and perhaps surprisingly, the presence of faults induces the robots to perform some form of scattering, rather than point-convergence. In fact, we discover that they arrange themselves inside the segment delimited by the two faults in interleaved sequences of equidistant robots.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.University of OttawaOttawaCanada

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