Towards real-world HTN planning agents

Abstract

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. This chapter first presents an online planning agent algorithm that integrates forward-chaining HTN planning, execution, belief updates, and plan modifications. In stratified multi-agent planning, the parent planning agent and its child planning agents work together to achieve a goal. The parent planning agent executes a rough plan for a goal, and the child planning agents execute detailed plans for subgoals. Although this stratified multi-agent planning is efficient, it is difficult for the parent planning agent to change the plan while a child planning agent is working. This chapter also shows how to realize online planning in stratified multi-agent planning. © 2009 Springer-Verlag Berlin Heidelberg.