Enriching a Temporal Planner with Resources and a Hierarchy-Based Heuristic

A key enabling feature to deploy a plan-based application for solving real world problems is the capability to integrate Planning and Scheduling (P&S) in the solving approach. Flexible Timeline-based Planning has been successfully applied in several real contexts to solve P&S problems. In this regard, we developed the Extensible Planning and Scheduling Library (Epsl) aiming at supporting the design of P&S applications. This paper describes some recent advancements in extending the Epsl framework by introducing the capability to reason about different types of "components", i.e., state variables and renewable resources, and allowing a tight integration of Planning and Scheduling techniques. Moreover, we present a domain independent heuristic function supporting the solving process by exploiting the hierarchical structure of the set of timelines making up the flexible plan. Some empirical results are reported to show the feasibility of deploying an Epsl-based P&S application in a real-world manufacturing case study.