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Multi-Agent Path Finding with Tasks Under Time Uncertainty

Authors Alexandre Albore , Christophe Grand , Noëlie Ramuzat , Ajdin Sumic

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Subject Classification

ACM Subject Classification
  • Computing methodologies → Multi-agent planning
  • Computing methodologies → Planning under uncertainty
  • Computing methodologies → Temporal reasoning
Keywords
  • Multi-Agent Path Finding
  • Temporal Uncertainty
  • Conflict Based Search
  • Simple Temporal Network

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Abstract

Multi-Agent Path Finding under Time Uncertainty (MAPF-TU) extends classical MAPF by considering uncertain traversal duration. However, existing approaches, such as the Conflict Based Search with Time Uncertainty (CBS_TU) method, assume that uncertainty only arises while agents move between locations, overlooking uncertainty induced by executing tasks. In many real-world applications, agents must not only navigate but also perform tasks of uncertain duration at specific locations, leading to additional temporal dependencies.
In this paper, we introduce Multi-Agent Path Finding with Tasks under Time Uncertainty (MAPF-TTU), a new extension of MAPF-TU in which agents must execute tasks of uncertain duration at intermediate goals. We first analyze the computational complexity of MAPF-TU and MAPF-TTU. We then propose two complementary solution approaches. The first extends CBS_TU to explicitly reason about uncertain task execution during planning. The second transforms an MAPF-TU solution into a Simple Temporal Network with Uncertainty (STNU) and computes a robust execution schedule through Strong Controllability.
Finally, we experimentally evaluate both approaches under varying levels of traversal and task time uncertainty, highlighting the tradeoff between solution quality and scalability.

Cite As Get BibTex

Alexandre Albore, Christophe Grand, Noëlie Ramuzat, and Ajdin Sumic. Multi-Agent Path Finding with Tasks Under Time Uncertainty. In 33rd International Symposium on Temporal Representation and Reasoning (TIME 2026). Open Access Series in Informatics (OASIcs), Volume 146, pp. 13:1-13:21, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/OASIcs.TIME.2026.13

Author Details

Alexandre Albore
  • ONERA, University of Toulouse, France
Christophe Grand
  • ONERA, University of Toulouse, France
Noëlie Ramuzat
  • ONERA, University of Toulouse, France
Ajdin Sumic
  • ONERA, University of Toulouse, France

Funding

This work was supported by government funding administered by the French National Research Agency (ANR) under the France 2030 programme, reference number ANR-23-DMRO-0006.

Supplementary Materials

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