{"type":"ScholarlyArticle","title":"Improved Heuristics for Multi-Agent Path Finding with Conflict-Based Search","authors":[{"name":"Jiaoyang Li","slug":"jiaoyang-li","given":"Jiaoyang","family":"Li","affiliation":"University of Southern California"},{"name":"Ariel Felner","slug":"ariel-felner","given":"Ariel","family":"Felner","affiliation":"Ben Gurion University of the Negev"},{"name":"Eli Boyarski","slug":"eli-boyarski","given":"Eli","family":"Boyarski","affiliation":"Ben Gurion University of the Negev"},{"name":"Hang Ma","slug":"hang-ma","given":"Hang","family":"Ma","affiliation":"University of Southern California"},{"name":"Sven Koenig","slug":"sven-koenig","given":"Sven","family":"Koenig","affiliation":"University of Southern California"}],"abstract":"Conflict-Based Search (CBS) and its enhancements are among the strongest algorithms for Multi-Agent Path Finding. Recent work introduced an admissible heuristic to guide the high-level search of CBS. In this work, we prove the limitation of this heuristic, as it is based on cardinal conflicts only. We then introduce two new admissible heuristics by reasoning about the pairwise dependencies between agents. Empirically, CBS with either new heuristic significantly improves the success rate over CBS with the recent heuristic and reduces the number of expanded nodes and runtime by up to a factor of 50.","doi":"10.24963/ijcai.2019/63","url":"https://ijcai.org/proceedings/2019/63","pdf":"https://ijcai.org/proceedings/2019/0063.pdf","markdown":"https://ijcai.org/proceedings/2019/63.md","bibtex":"https://ijcai.org/proceedings/2019/bibtex/63","volume":{"slug":"2019","title":"Proceedings of the Twenty-Eighth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2019","url":"https://ijcai.org/proceedings/2019/","year":2019,"location":"Macao","dates":"10-16 August 2019","editors":"Sarit Kraus","isbn":"978-0-9992411-4-1","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2019"},"section":"Agent-based and Multi-agent Systems","track":"Main track","number":63,"pages":{"first":442,"last":449},"keywords":["Agent-based and Multi-agent Systems: Multi-agent Planning","Planning and Scheduling: Search in Planning and Scheduling","Heuristic Search and Game Playing: Heuristic Search","Heuristic Search and Game Playing: Combinatorial Search and Optimisation"],"videos":[],"references":[{"position":1,"raw":"[Barer et al., 2014] Max Barer, Guni Sharon, Roni Stern, and Ariel Felner. 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