A Fuzzy Set Semantics for Qualitative Fluents in the Situation Calculus

  • Alexander Ferrein
  • Stefan Schiffer
  • Gerhard Lakemeyer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5314)


Specifying the behavior of an intelligent autonomous robot or agent is a non-trivial task. The question is: how can the knowledge of the domain expert be encoded in the agent program? Qualitative representations in general facilitate to express the knowledge of a domain expert. In this paper, we propose a semantics for qualitative fluents in the situation calculus. Our semantics is based on fuzzy sets. Membership functions define to which degree a qualitative fluent belongs to a particular category. Especially intriguing about a fuzzy set semantics for qualitative fluents is that the qualitative ranges may overlap, and a value can, at the same time, fall into several categories.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Alexander Ferrein
    • 1
  • Stefan Schiffer
    • 1
  • Gerhard Lakemeyer
    • 1
  1. 1.Knowledge-Based Systems GroupRWTH Aachen UniversityAachenGermany

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