Review of replanning in hierarchical task network.

As an important part of the intelligent planning technology, hierarchical task network (HTN) is successfully applied to the task planning in unmanned aerial vehicle platform, emergency plan formulation and other fields. Due to effect the increasing uncertain factors on the implementation the influence of the plan, it is urgent to use replanning technology, thus the replanning technology based on HTN has become a hotspot in recent years. First of all, a three-layer replan framework based on HTN is proposed by summarizing the current research status. Then, the corresponding technical route and implementation details are represented from three levels of plan repair, local replanning and global replanning in the framework respectively, and the advantages and disadvantages of the current method are pointed out for different levels. Finally, the future research direction of this problem is prospected, and the key problems to be solved and the solutions are putting forward. [ABSTRACT FROM AUTHOR]