Temporal Planning with Mutual Exclusion Reasoning

Many planning domains require a richer notion of time in which actions can overlap and have di erent durations. The key to fast performance in classical planners (e.g., Graphplan, ipp, and Blackbox) has been the use of a disjunctive representation with powerful mutual exclusion reasoning. This paper presents tgp, a new algorithm for temporal planning. tgp operates by incrementally expanding a compact planning graph representation that handles actions of di ering duration. The key to tgp performance is tight mutual exclusion reasoning which is based on an expressive language for bounding mutexes and includes mutexes between actions and propositions. Our experiments demonstrate that mutual exclusion reasoning remains valuable in a rich temporal setting.