Patrolling a Path Connecting a Set of Points with Unbalanced Frequencies of Visits

  • Huda Chuangpishit
  • Jurek Czyzowicz
  • Leszek Gąsieniec
  • Konstantinos Georgiou
  • Tomasz Jurdziński
  • Evangelos Kranakis
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10706)


Patrolling consists of scheduling perpetual movements of a collection of mobile robots, so that each point of the environment is regularly revisited by any robot in the collection. In previous research, it was assumed that all points of the environment needed to be revisited with the same minimal frequency.

In this paper we study efficient patrolling protocols for points located on a path, where each point may have a different constraint on frequency of visits. The problem of visiting such divergent points was recently posed by Gąsieniec et al. in [14], where the authors study protocols using a single robot patrolling a set of n points located in nodes of a complete graph and in Euclidean spaces.

The focus in this paper is on patrolling with two robots. We adopt a scenario in which all points to be patrolled are located on a line. We provide several approximation algorithms concluding with the best currently known \(\sqrt{3}\)-approximation.


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Huda Chuangpishit
    • 1
  • Jurek Czyzowicz
    • 2
  • Leszek Gąsieniec
    • 3
  • Konstantinos Georgiou
    • 1
  • Tomasz Jurdziński
    • 4
  • Evangelos Kranakis
    • 5
  1. 1.Department of MathematicsRyerson UniversityTorontoCanada
  2. 2.Département d’informatiqueUniversité du Québec en OutaouaisGatineauCanada
  3. 3.Department of Computer ScienceUniversity of LiverpoolLiverpoolUK
  4. 4.Instytut InformatykiUniwersytet WrocławskiWrocławPoland
  5. 5.School of Computer ScienceCarleton UniversityOttawaCanada

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