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arXiv · 2501.16743

Hierarchical Trajectory (Re)Planning for a Large Scale Swarm

Lishuo Pan·Yutong Wang·Nora Ayanian
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Abstract

We consider the trajectory replanning problem for a large-scale swarm in a cluttered environment. Our path planner replans for robots by utilizing a hierarchical approach, dividing the workspace, and computing collision-free paths for robots within each cell in parallel. Distributed trajectory optimization generates a deadlock-free trajectory for efficient execution and maintains the control feasibility even when the optimization fails. Our hierarchical approach combines the benefits of both centralized and decentralized methods, achieving a high task success rate while providing real-time replanning capability. Compared to decentralized approaches, our approach effectively avoids deadlocks and collisions, significantly increasing the task success rate. We demonstrate the real-time performance of our algorithm with up to 142 robots in simulation, and a representative 24 physical Crazyflie nano-quadrotor experiment.

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Lishuo Pan, Yutong Wang, Nora Ayanian. 2025-01-28. Hierarchical Trajectory (Re)Planning for a Large Scale Swarm. https://arxiv.org/abs/2501.16743

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