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Title: Replanning in Advance for Instant Delay Recovery in Multi-Agent Applications: Rerouting Trains in a Railway Hub
Train routing is sensitive to delays that occur in the network. When a train is delayed, it is imperative that a new plan be found quickly, or else other trains may need to be stopped to ensure safety, potentially causing cascading delays. In this paper, we consider this class of multi-agent planning problems, which we call Multi-Agent Execution Delay Replanning. We show that these can be solved by reducing the problem to an any-start-time safe interval planning problem. When an agent has an any-start-time plan, it can react to a delay by simply looking up the precomputed plan for the delayed start time. We identify crucial real-world problem characteristics like the agent's speed, size, and safety envelope, and extend the any-start-time planning to account for them. Experimental results on real-world train networks show that any-start-time plans are compact and can be computed in reasonable time while enabling agents to instantly recover a safe plan.  more » « less
Award ID(s):
2008594
PAR ID:
10546018
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AAAI Press
Date Published:
Journal Name:
Proceedings of the International Conference on Automated Planning and Scheduling
Volume:
34
ISSN:
2334-0835
Page Range / eLocation ID:
258 to 266
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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