Dynagent: An Incremental Forward-Chaining HTN Planning Agent in Dynamic Domains

  • Hisashi Hayashi
  • Seiji Tokura
  • Tetsuo Hasegawa
  • Fumio Ozaki
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3904)


HTN planning, especially forward-chaining HTN planning, is becoming important in the areas of agents and robotics, which have to deal with the dynamically changing world. Therefore, replanning in “forward-chaining” HTN planning has become an important subject for future study. This paper presents the new agent algorithm that integrates forward-chaining HTN planning, execution, belief updates, and plan modifications. Also, through combination with an A*-like heuristic search strategy, we show that our agent algorithm is effective for the replanning problem of museum tour guide robots, which is similar to the replanning problem of a traveling salesman.


Planning Algorithm Action Execution Protected Condition Plan Execution Action Rule 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Hisashi Hayashi
    • 1
  • Seiji Tokura
    • 2
  • Tetsuo Hasegawa
    • 1
  • Fumio Ozaki
    • 2
  1. 1.Knowledge Media Laboratory, R&D CenterToshiba CorporationKawasakiJapan
  2. 2.Humancentric Laboratory, R&D CenterToshiba CorporationKawasakiJapan

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