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Traditional multi-agent path finding (MAPF) methods try to compute entire collision free start-goal paths, with several algorithms offering completeness guarantees. However, computing partial paths offers significant advantages including faster planning, adaptability to changes, and enabling decentralized planning. Methods that compute partial paths employ a windowed approach and only try to find collision free paths for a limited timestep horizon. While this improves flexibility, this adaptation introduces incompleteness; all existing windowed approaches can become stuck in deadlock or livelock. Our main contribution is to introduce our framework, WinC-MAPF, for Windowed MAPF that enables completeness. Our framework leverages heuristic update insights from single-agent real-time heuristic search algorithms and agent independence ideas from MAPF algorithms. We also develop Single-Step Conflict Based Search (SS-CBS), an instantiation of this framework using a novel modification to CBS. We show how SS-CBS, which only plans a single step and updates heuristics, can effectively solve tough scenarios where existing windowed approaches fail.
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This content will become publicly available on July 20, 2026
Real-time Cost-algebraic Heuristic Search
Planning under time pressure arises in many situations. Real-time heuristic search, in which an agent must compute its next action within a prespecified time bound, has proven to be a useful model of real-time planning. However, it is laborious to prove the completeness of new real-time search algorithms. In this paper, we provide a general proof of the completeness of a standard real-time heuristic search algorithm in any problem domain that obeys the axioms of a cost algebra. The proof includes additional detail on how h values change as the algorithm learns. This foundation clarifies the dependence of the proof on domain and algorithm properties and will ease future applications of real-time planning.
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- Award ID(s):
- 2008594
- PAR ID:
- 10654181
- Publisher / Repository:
- AAAI Press
- Date Published:
- Journal Name:
- Proceedings of the International Symposium on Combinatorial Search
- Volume:
- 18
- ISSN:
- 2832-9171
- Page Range / eLocation ID:
- 162 to 170
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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