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Multi-agent Path Finding with Capacity Constraints

  • Pavel SurynekEmail author
  • T. K. Satish Kumar
  • Sven Koenig
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11946)

Abstract

In multi-agent path finding (MAPF) the task is to navigate agents from their starting positions to given individual goals. The problem takes place in an undirected graph whose vertices represent positions and edges define the topology. Agents can move to neighbor vertices across edges. In the standard MAPF, space occupation by agents is modeled by a capacity constraint that permits at most one agent per vertex. We suggest an extension of MAPF in this paper that permits more than one agent per vertex. Propositional satisfiability (SAT) models for these extensions of MAPF are studied. We focus on modeling capacity constraints in SAT-based formulations of MAPF and evaluation of performance of these models. We extend two existing SAT-based formulations with vertex capacity constraints: MDD-SAT and SMT-CBS where the former is an approach that builds the model in an eager way while the latter relies on lazy construction of the model.

Keywords

Multi agent path finding propositional satisfiability (SAT) Capacity constraints Cardinality constraints 

Notes

Acknowledgements

This research has been supported by GAČR - the Czech Science Foundation, grant registration number 19-17966S.

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Faculty of Information TechnologyCzech Technical University in PraguePraha 6Czechia
  2. 2.Henry Salvatori Computer Science CenterUniversity of Southern CaliforniaLos AngelesUSA
  3. 3.Information Sciences InstituteUniversity of Southern CaliforniaMarina del ReyUSA

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