A game-theoretic approach to timeline-based planning with uncertainty

TL;DR

This paper introduces a game-theoretic framework for timeline-based planning that handles both temporal uncertainty and nondeterminism, expanding the capabilities of existing planning methods.

Contribution

It generalizes the concept of control strategies to include winning strategies in timeline-based games, addressing more complex uncertainties.

Findings

Winning strategies are more general than control strategies.

Existence of winning strategies is decidable with doubly exponential space.

The approach unifies handling of temporal uncertainty and nondeterminism.

Abstract

In timeline-based planning, domains are described as sets of independent, but interacting, components, whose behaviour over time (the set of timelines) is governed by a set of temporal constraints. A distinguishing feature of timeline-based planning systems is the ability to integrate planning with execution by synthesising control strategies for flexible plans. However, flexible plans can only represent temporal uncertainty, while more complex forms of nondeterminism are needed to deal with a wider range of realistic problems. In this paper, we propose a novel game-theoretic approach to timeline-based planning problems, generalising the state of the art while uniformly handling temporal uncertainty and nondeterminism. We define a general concept of timeline-based game and we show that the notion of winning strategy for these games is strictly more general than that of control strategy for dynamically controllable flexible plans. Moreover, we show that the problem of establishing the existence of such winning strategies is decidable using a doubly exponential amount of space.