On the Benefit of Fusing DL-Reasoning with HTN-Planning

Keeping planning problems as small as possible is a must in order to cope with complex tasks and environments. Earlier, we have described a method for cascading Description Logic (dl) representation and reasoning on the one hand, and Hierarchical Task Network (htn) action planning on the other. The planning domain description as well as the fundamental htn planning concepts are represented in dl and can therefore be subject to dl reasoning. From these representations, concise planning problems are generated for htn planners. We show by way of case study that this method yields significantly smaller planning problem descriptions than regular representations do in htn planning. The method is presented through a case study of a robot navigation domain and the blocks world domain. We present the benefits of using this approach in comparison with a pure htn planning approach.