Tree-Structured Recursive Arc Spline Approximation of Complex Lane-Level Maps with G1 Continuity
摘要
As autonomous and ADAS technologies evolve, the demand for high definition (HD) lane-level maps has increased. Polyline formats, which represent lane geometry as a sequence of discrete points, are widely used in industrial HD maps due to their simplicity. However, they lack continuous geometric properties such as curvature and heading angle, making them less suitable for trajectory planning and motion control. To address this, curve-based parameterization methods have been introduced to provide a more structured representation of lane geometries. Despite their advantages, existing curve-based approaches struggle to maintain global G1 continuity and effectively model complex road structures, such as densely interconnected intersections. This study proposes an arc spline approximation framework that ensures global G1 continuity while employing a tree-based recursive parameterization approach for efficient handling of large-scale road networks. Validation using lanelet maps from the nuScenes dataset demonstrates that the framework achieves precise approximations across diverse road structures while significantly enhancing geometric fidelity compared to polyline-based formats.