Safe Interval Motion Planning for Quadrotors in Dynamic Environments

Songhao Huang; Yuwei Wu; Yuezhan Tao; Vijay Kumar

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arXiv · 2409.10647

Safe Interval Motion Planning for Quadrotors in Dynamic Environments

Songhao Huang·Yuwei Wu·Yuezhan Tao·Vijay Kumar

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Abstract

Trajectory generation in dynamic environments presents a significant challenge for quadrotors, particularly due to the non-convexity in the spatial-temporal domain. Many existing methods either assume simplified static environments or struggle to produce optimal solutions in real-time. In this work, we propose an efficient safe interval motion planning framework for navigation in dynamic environments. A safe interval refers to a time window during which a specific configuration is safe. Our approach addresses trajectory generation through a two-stage process: a front-end graph search step followed by a back-end gradient-based optimization. We ensure completeness and optimality by constructing a dynamic connected visibility graph and incorporating low-order dynamic bounds within safe intervals and temporal corridors. To avoid local minima, we propose a Uniform Temporal Visibility Deformation (UTVD) for the complete evaluation of spatial-temporal topological equivalence. We represent trajectories with B-Spline curves and apply gradient-based optimization to navigate around static and moving obstacles within spatial-temporal corridors. Through simulation and real-world experiments, we show that our method can achieve a success rate of over 95% in environments with different density levels, exceeding the performance of other approaches, demonstrating its potential for practical deployment in highly dynamic environments.

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BibTeX RIS

Songhao Huang, Yuwei Wu, Yuezhan Tao, Vijay Kumar. 2025-03-18. Safe Interval Motion Planning for Quadrotors in Dynamic Environments. https://arxiv.org/abs/2409.10647

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