Temporal Planning using Subgoal Partitioning and Resolution in SGPlan

In this paper, we present the partitioning of mutual-exclusion (mutex) constraints in temporal planning problems and its implementation in the SGPlan4 planner. Based on the strong locality of mutex constraints observed in many benchmarks of the Fourth International Planning Competition (IPC4), we propose to partition the constraints of a planning problem into groups based on their subgoals. Constraint partitioning leads to significantly easier subproblems that are similar to the original problem and that can be efficiently solved by the same planner with some modifications to its objective function. We present a partition-and-resolve strategy that looks for locally optimal subplans in constraint-partitioned temporal planning subproblems and that resolves those inconsistent global constraints across the subproblems. We also discuss some implementation details of SGPlan4, which include the resolution of violated global constraints, techniques for handling producible resources, landmark ...

• Type: Journal
• Year: 2006
• Where: JAIR
• Authors: Yixin Chen, Benjamin W. Wah, Chih-Wei Hsu
• Keywords: Global Constraints, JAIR 2006, Planning Problem, Temporal Planning