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arXiv · 2209.15150

Spatio-temporal Motion Planning for Autonomous Vehicles with Trapezoidal Prism Corridors and B\'{e}zier Curves

Srujan Deolasee·Qin Lin·Jialun Li·John M. Dolan
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Abstract

Safety-guaranteed motion planning is critical for self-driving cars to generate collision-free trajectories. A layered motion planning approach with decoupled path and speed planning is widely used for this purpose. This approach is prone to be suboptimal in the presence of dynamic obstacles. Spatial-temporal approaches deal with path planning and speed planning simultaneously; however, the existing methods only support simple-shaped corridors like cuboids, which restrict the search space for optimization in complex scenarios. We propose to use trapezoidal prism-shaped corridors for optimization, which significantly enlarges the solution space compared to the existing cuboidal corridors-based method. Finally, a piecewise B\'{e}zier curve optimization is conducted in our proposed corridors. This formulation theoretically guarantees the safety of the continuous-time trajectory. We validate the efficiency and effectiveness of the proposed approach in numerical and CommonRoad simulations.

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Srujan Deolasee, Qin Lin, Jialun Li, John M. Dolan. 2022-09-30. Spatio-temporal Motion Planning for Autonomous Vehicles with Trapezoidal Prism Corridors and B\'{e}zier Curves. https://arxiv.org/abs/2209.15150

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