Conflict-Based Search For Optimal Multi-Agent Path Finding


  • Guni Sharon Ben-Gurion University
  • Roni Stern Ben-Gurion University
  • Ariel Felner Ben-Gurion University
  • Nathan Sturtevant University of Denver



Heuristic Search, Multiagent pathfinding


In the multi agent path finding problem (MAPF) paths should be found for several agents, each with a different start and goal position such that agents do not collide. Previous optimal solvers applied global A*-based searches. We present a new search algorithm called Conflict Based Search (CBS). CBS is a two-level algorithm. At the high level, a search is performed on a tree based on conflicts between agents. At the low level, a search is performed only for a single agent at a time. In many cases this reformulation enables CBS to examine fewer states than A* while still maintaining optimality. We analyze CBS and show its benefits and drawbacks. Experimental results on various problems shows a speedup of up to a full order of magnitude over previous approaches.




How to Cite

Sharon, G., Stern, R., Felner, A., & Sturtevant, N. (2021). Conflict-Based Search For Optimal Multi-Agent Path Finding. Proceedings of the AAAI Conference on Artificial Intelligence, 26(1), 563-569.



Constraints, Satisfiability, and Search