Visualizing Actions in a Plan Graph Persistence actions ( Noops) Every literal has a no-op action, which maintains it from time i to i+l E. g, ( operator noop-P: precondition(P): effect(P)) A Plan in GraphPlan <Actions[> ets of concurrent actions performed at each time il Concurrent actions can be interleaved in any order If actions a and b occur at time i. then it must be valid to perform either a followed by b, OR b followed by a noGarb clean carry. clean cook noop-dinner nner dinne noop-present present present Prop at 1 Action at 1 Prop at 2 Action at 2 Prop at 217 • Persistence actions (Noops) • • E.g., (:operator noop-P (P) :effect (P)) Noop-P P P Visualizing Actions in a Plan Graph dinner present cook wrap cleanH carry quiet noGarb cleanH dinner present Prop at 1 Action at 1 Prop at 2 Action at 2 Prop at 2 noop-dinner noop-present • Sets of concurrent actions performed at each time [i] • Concurrent actions can be interleaved in any order. • If actions a and b occur at time i, then it must be valid to Actions[i] > :precondition A Plan in GraphPlan < Every literal has a no-op action, which maintains it from time i to i+1. perform either a followed by b, OR b followed by a