Section: New Results

Searching for Cost-Optimized Strategies. Application to Temporal Planning and Agricultural System

Participants : Christine Largouët, Marie-Odile Cordier.

We consider a system modeled as a set of interacting components evolving along time according to explicit timing constraints. The decision making problem consists in selecting and organizing actions in order to reach a goal state in a limited time and in an optimal manner, assuming actions have a cost. We propose to reformulate the planning problem in terms of model-checking and controller synthesis such that the state to reach is expressed using a temporal logic. We have chosen to represent each agent using the formalism of Priced Timed Game Automata (PTGA) and a set of knowledge. PTGA is an extension of Timed Automata that allows the representation of cost on actions and the definition of a goal (to reach or to avoid). A first paper describes two algorithms designed to address the planning problem on a network of agents and proposes a practical implementation using model-checking tools that shows promising results on an agricultural application: a grassland based dairy production system [9]. Another paper describes the expressivity of this approach on the classical Transport Domain which is extended in order to include timing constraints, cost values and uncontrollable actions. This work has been implemented and performances evaluated on benchmarks [8].