PIPES: A heuristic search model for pipeline schedule generation

Resource scheduling problems are increasingly being solved using Al techniques. Solving real-life versions of these problems demands the ability to model a range of constraints and, at the same time, to be flexible enough to make revisions to these constraints. In this paper, we outline the pipeline schedule generation problem, where the task is to generate a pumping schedule for a single-source multiple-destinations oil pipeline carrying multiple products. The schedule must take into account product availability and requirements while satisfying a wide variety of domain constraints, including tankage constraints, product sequencing constraints, quality control constraints, delivery constraints, etc. We describe an approach based on heuristic search, which we have adopted for solving it. The system has been successfully implemented and is in use. (C) 1997 Elsevier Science B.V.