Combining Strategical and Tactical Decisions in Scheduling Office Delivery Activities

This paper investigates a novel approach to integrating tactical and strategical decision making and applies it to scheduling the operation of autonomous robot office couriers. In this approach the robot makes strategical (farsighted) decisions while it executes a plan using tactical (immediate) decisions and overwrites tactical decisions after strategical decisions have been reached (if necessary). The novel features of this approach are that tactical and strategical decision making is implemented as plan transformation and specified using declarative plan transformation rules. The advantages are that (1) decisions are represented explicitly so that they can be revised again and (2) that all decision making is specified within the plan and not hidden in a separate execution system. We present experiments in which the approach is used to control two autonomous mobile robots. In one of them it controlled the course of action of a museums tourguide robot that has operated for thirteen days, more than 94 hours, and presented 2668 exhibits.