On the Completeness of Conflict-Based Search: Temporally-Relative Duplicate Pruning
<|reference_start|>On the Completeness of Conflict-Based Search: Temporally-Relative Duplicate Pruning: Conflict-Based Search (CBS) algorithm for the multi-agent pathfinding (MAPF) problem is that it is incomplete for problems which have no solution; if no mitigating procedure is run in parallel, CBS will run forever when given an unsolvable problem instance. In this work, we introduce Temporally-Relative Duplicate Pruning (TRDP), a technique for duplicate detection and removal in both classic and continuous-time MAPF domains. TRDP is a simple procedure which closes the long-standing theoretic loophole of incompleteness for CBS by detecting and avoiding the expansion of duplicate states. TRDP is shown both theoretically and empirically to ensure termination without a significant impact on runtime in the majority of problem instances. In certain cases, TRDP is shown to increase performance significantly<|reference_end|>
@article{walker2024on,
    title={On the Completeness of Conflict-Based Search: Temporally-Relative
  Duplicate Pruning},
    author={Thayne T Walker and Nathan R Sturtevant},
    journal={arXiv preprint arXiv:2408.09028},
    year={2024},
    archivePrefix={arXiv},
    eprint={2408.09028},
    primaryClass={cs.AI cs.RO}
}