Asynchronous Rendezvous with Different Maps

  • Serafino CiceroneEmail author
  • Gabriele Di Stefano
  • Leszek Gąsieniec
  • Alfredo Navarra
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11639)


This paper provides a study on the rendezvous problem in which two anonymous mobile entities referred to as robots \(r_A\) and \(r_B\) are asked to meet at an arbitrary node of a graph \(G = (V,E)\). As opposed to more standard assumptions robots may not be able to visit the entire graph G. Namely, each robot has its own map which is a connected subgraph of G. Such mobility restrictions may be dictated by the topological properties combined with the intrinsic characteristics of robots preventing them from visiting certain edges in E.

We consider four different variants of the rendezvous problem introduced in [Farrugia et al. SOFSEM’15] which reflect on restricted maneuverability and navigation ability of \(r_A\) and \(r_B\) in G. In the latter, the focus is on models in which robots’ actions are synchronised. The authors prove that one of the maps must be a subgraph of the other. I.e., without this assumption (or some extra knowledge) the rendezvous problem does not have a feasible solution. In this paper, while we keep the containment assumption, we focus on asynchronous robots and the relevant bounds in the four considered variants. We provide some impossibility results and almost tight lower and upper bounds when the solutions are possible.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Serafino Cicerone
    • 1
    Email author
  • Gabriele Di Stefano
    • 1
  • Leszek Gąsieniec
    • 2
  • Alfredo Navarra
    • 3
  1. 1.Department of Information Engineering, Computer Science and MathematicsUniversity of L’AquilaL’AquilaItaly
  2. 2.Department of Computer ScienceUniversity of LiverpoolLiverpoolUK
  3. 3.Department of Mathematics and Computer ScienceUniversity of PerugiaPerugiaItaly

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