Group Search and Evacuation

  • Jurek Czyzowicz
  • Kostantinos Georgiou
  • Evangelos KranakisEmail author
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11340)


Group search and evacuation are fundamental tasks performed by a set of co-operating, autonomous mobile agents. The two tasks are similar in that they both aim to search a given domain so as to locate a target which has been placed at an unknown location in the domain. However they also differ in that the former terminates when the first searcher in the group reaches the target while the latter when the last searcher in the group reaches the target. Variations where termination is determined by some designated agent have also been considered. Depending on the domain being explored we distinguish linear search when the target is placed on the infinite line and circular search when the target is placed on the perimeter of a disk. The agents move with their own maximum speed, and the goal is to design algorithms that minimize the worst case termination time. Two communication models between the robots are being considered: in the non-wireless (or face-to-face) communication model, robots exchange information only when simultaneously located at the same point, and wireless communication in which robots can communicate with one another anywhere at any time. In this paper we survey some of the most interesting recent algorithmic results on search and evacuation concerning mobile agents with and without faults.


Autonomous agents Cycle Evacuation Exit Line Search 



We would like to express our deepest appreciation to our colleagues Stefan Dobrev, Leszek Gasieniec, Maxime Godon, Danny Krizanc, Fraser MacQuarrie, Russell Martin, Dominik Pajak, Oscar Morales Ponce, Lata Narayanan, and Jarda Opatrny for numerous interesting conversations that excited our interests on all aspects of search and evacuation.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Jurek Czyzowicz
    • 1
  • Kostantinos Georgiou
    • 2
  • Evangelos Kranakis
    • 3
    Email author
  1. 1.Dépt. d’informatiqueUniv. du Québec en OutaouaisGatineauCanada
  2. 2.Department of MathematicsRyerson UniversityTorontoCanada
  3. 3.School of Computer ScienceCarleton UniversityOttawaCanada

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