Real-Time Reasoning in Deadline Situations,

Abstract : In deadline situations the salient resource is time: all preparations must be carried out in advance of the deadline. If action is called for, an appropriate plan must be formulated and enacted before the deadline. This puts interesting constraints on the reasoning that goes into forming the plan and its simultaneous or subsequent execution. Step-logics were introduced as a mechanism for reasoning situated in time. We first describe them in brief. We then show their application to creating a step-logic planner that lets a time-situated reasoner keep track of an approaching deadline as she/he makes (and enacts) her/his plan, thereby treating all facets of planning (including plan-formation and its simultaneous or subsequent execution) as deadline-coupled. We use a key example of a tight deadline situation to illustrate the problem and our approach.