Logic-Based Encodings for Ricochet Robots

  • Filipe Gouveia
  • Pedro T. Monteiro
  • Vasco Manquinho
  • Inês Lynce
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10423)


Studying the performance of logic tools on solving a specific problem can bring new insights on the use of different paradigms. This paper provides an empirical evaluation of logic-based encodings for a well known board game: Ricochet Robots. Ricochet Robots is a board game where the goal is to find the smallest number of moves needed for one robot to move from the initial position to a target position, while taking into account the existing barriers and other robots. Finding a solution to the Ricochet Robots problem is NP-hard. In this work we develop logic-based encodings for the Ricochet Robots problem to feed into Boolean Satisfiability (SAT) solvers. When appropriate, advanced techniques are applied to further boost the performance of a solver. A comparison between the performance of SAT solvers and an existing ASP solution clearly shows that SAT is by far the more adequate technology to solve the Ricochet Robots problem.


Ricochet Robots Encodings Boolean Satisfiability Answer Set Programming 


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Filipe Gouveia
    • 1
  • Pedro T. Monteiro
    • 1
  • Vasco Manquinho
    • 1
  • Inês Lynce
    • 1
  1. 1.INESC-ID/Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal

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