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A Complete Algorithm for Generating Safe Trajectories for Multi-robot Teams

Part of the Springer Proceedings in Advanced Robotics book series (SPAR,volume 3)


In this paper, we consider the problem of planning collision-free trajectories to navigate a team of labeled robots from a set of start locations to a set of goal locations, where robots have pre-assigned and non-interchangeable goals. We present a solution to this problem for a centralized team operating in an obstacle-free, two-dimensional workspace. Our algorithm allows robots to follow Optimal Motion Plans (OMPs) to their goals when possible and has them enter Circular HOlding Patterns (CHOPs) to safely navigate congested areas. This OMP\(+\)CHOP algorithm is shown to be safe and complete, and simulation results show scalability to hundreds of robots.


  • Optimal Motion Planning (OMP)
  • Motion Plan
  • Optimal Reciprocal Collision Avoidance (ORCA)
  • Intermediate Waypoints
  • Unmanned Aircraft Systems (UASs)

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  • DOI: 10.1007/978-3-319-60916-4_34
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We gratefully acknowledge the support of ONR grants N00014-09-1-1051 and N00014-09-1-103, NSF grant IIS-1426840, and Exyn Technologies. Sarah Tang is supported by NSF Research Fellowship Grant No. DGE-1321851. The authors would also like to thank Levi Cai from the University of Pennsylvania for his implementation of the M* algorithm.

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Tang, S., Kumar, V. (2018). A Complete Algorithm for Generating Safe Trajectories for Multi-robot Teams. In: Bicchi, A., Burgard, W. (eds) Robotics Research. Springer Proceedings in Advanced Robotics, vol 3. Springer, Cham.

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