cost-optimal plan
Planning with Minimal Disruption
Pozanco, Alberto, Morales, Marianela, Borrajo, Daniel, Veloso, Manuela
In many planning applications, we might be interested in finding plans that minimally modify the initial state to achieve the goals. We refer to this concept as plan disruption. In this paper, we formally introduce it, and define various planning-based compilations that aim to jointly optimize both the sum of action costs and plan disruption. Experimental results in different benchmarks show that the reformulated task can be effectively solved in practice to generate plans that balance both objectives.
On Computing Plans with Uniform Action Costs
Pozanco, Alberto, Borrajo, Daniel, Veloso, Manuela
In many real-world planning applications, agents might be interested in finding plans whose actions have costs that are as uniform as possible. Such plans provide agents with a sense of stability and predictability, which are key features when humans are the agents executing plans suggested by planning tools. This paper adapts three uniformity metrics to automated planning, and introduce planning-based compilations that allow to lexicographically optimize sum of action costs and action costs uniformity. Experimental results both in well-known and novel planning benchmarks show that the reformulated tasks can be effectively solved in practice to generate uniform plans.
Solving Delete Free Planning with Relaxed Decision Diagram Based Heuristics
Castro, Margarita Paz (University of Toronto) | Piacentini, Chiara (Autodesk Research) | Cire, Andre Augusto (Dept. of Management, University of Toronto Scarborough and Rotman School of Management) | Beck, J. Christopher (Department of Mechanical and Industrial Engineering, University of Toronto)
We investigate the use of relaxed decision diagrams (DDs) for computing admissible heuristics for the cost-optimal delete-free planning (DFP) problem. Our main contributions are the introduction of two novel DD encodings for a DFP task: a multivalued decision diagram that includes the sequencing aspect of the problem and a binary decision diagram representation of its sequential relaxation. We present construction algorithms for each DD that leverage these different perspectives of the DFP task and provide theoretical and empirical analyses of the associated heuristics. We further show that relaxed DDs can be used beyond heuristic computation to extract delete-free plans, find action landmarks, and identify redundant actions. Our empirical analysis shows that while DD-based heuristics trail the state of the art, even small relaxed DDs are competitive with the linear programming heuristic for the DFP task, thus, revealing novel ways of designing admissible heuristics.
Planning Games
Brafman, Ronen I. (Ben-Gurion University) | Domshlak, Carmel (Technion - Israel Institute of Technology) | Engel, Yagil (Technion - Israel Institute of Technology) | Tennenholtz, Moshe (Microsoft Israel R&D Center)
We introduce planning games, a study of interactions of self-motivated agents in automated planning settings. Planning games extend STRIPS-like models of single-agent planning to systems of multiple self-interested agents, providing a rich class of structured games that capture subtle forms of local interactions. We consider two basic models of planning games and adapt game-theoretic solution concepts to these models. In both models, agents may need to cooperate in order to achieve their goals, but are assumed to do so only in order to increase their net benefit. For each model we study the computational problem of finding a stable solution and provide efficient algorithms for systems exhibiting acyclic interaction structure.