The FF Planning System: Fast Plan Generation Through Heuristic Search

@article{Hoffmann2001TheFP,
  title={The FF Planning System: Fast Plan Generation Through Heuristic Search},
  author={J{\"o}rg Hoffmann and Bernhard Nebel},
  journal={J. Artif. Intell. Res.},
  year={2001},
  volume={14},
  pages={253-302}
}
We describe and evaluate the algorithmic techniques that are used in the FF planning system. Like the HSP system, FF relies on forward state space search, using a heuristic that estimates goal distances by ignoring delete lists. Unlike HSP's heuristic, our method does not assume facts to be independent. We introduce a novel search strategy that combines hill-climbing with systematic search, and we show how other powerful heuristic information can be extracted and used to prune the search space… 

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