Title
Receding Horizon Re-Ordering of Multi-Agent Execution Schedules
Author
Berndt, Alexander (Overstory B.V.)
Van Duijkeren, Niels (Robert Bosch GmbH)
Palmieri, Luigi (Robert Bosch GmbH)
Kleiner, Alexander (Robert Bosch GmbH)
Keviczky, T. (TU Delft Team Tamas Keviczky) 
Date
2024
Abstract
The trajectory planning for a fleet of automated guided vehicles (AGVs) on a roadmap is commonly referred to as the multi-agent path finding (MAPF) problem, the solution to which dictates each AGV's spatial and temporal location until it reaches its goal without collision. When executing MAPF plans in dynamic workspaces, AGVs can be frequently delayed, e.g., due to encounters with humans or third-party vehicles. If the remainder of the AGVs keeps following their individual plans, synchrony of the fleet is lost and some AGVs may pass through roadmap intersections in a different order than originally planned. Although this could reduce the cumulative route completion time of the AGVs, generally, a change in the original ordering can cause conflicts, such as deadlocks. In practice, synchrony is therefore often enforced by using a MAPF execution policy employing, e.g., an action dependency graph (ADG) to maintain ordering. To safely re-order without introducing deadlocks, we present the concept of the switchable action dependency graph (SADG). Using the SADG, we formulate a comparatively low-dimensional mixed-integer linear program that repeatedly re-orders AGVs in a recursively feasible manner, thus maintaining deadlock-free guarantees, while dynamically minimizing the cumulative route completion time of all AGVs. Various simulations validate the efficiency of our approach when compared to the original ADG method as well as robust MAPF solution approaches.
Subject
Mixed integer programming
multi-agent path finding (MAPF)
robust plan execution
scheduling and coordination
To reference this document use:
http://resolver.tudelft.nl/uuid:98dcc7af-1d83-417f-9909-7308bdad9b9e
DOI
https://doi.org/10.1109/TRO.2023.3344051
Embargo date
2024-06-18
ISSN
1552-3098
Source
IEEE Transactions on Robotics, 40, 1356-1372
Bibliographical note
Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Part of collection
Institutional Repository
Document type
journal article
Rights
© 2024 Alexander Berndt, Niels Van Duijkeren, Luigi Palmieri, Alexander Kleiner, T. Keviczky