CSR: A Lightweight Crowdsourced Road Structure Reconstruction System for Autonomous Driving

Highly accurate and robust vectorized reconstruc- tion of road structures is crucial for autonomous vehicles. Tra- ditional LiDAR-based methods require multiple processes and are often expensive, time-consuming, labor-intensive, and cum- bersome. In this paper, we propose a lightweight crowdsourced road structure reconstruction system (termed CSR) that relies solely on online perceived semantic elements. Ambiguities and perceptual errors of semantic features and Global Navigation Satellite System (GNSS) global pose errors constitute the predominant challenge in achieving alignment across multi-trip data. To this end, a robust two-phased coarse-to-fine multi-trip alignment method is performed considering local geometric consistency, global topology consistency, intra-trip temporal consistency, and inter-trip consistency. Further, we introduce an incremental pose graph optimization framework with adaptive weight tuning ability to integrate pre-built road structures, currently perceived multi-trip semantic features, odometry, and GNSS, enabling accurate and robust incremental road structure reconstruction. CSR is highly automated, efficient, and scal- able for large-scale autonomous driving scenarios, significantly expediting road structure production. We quantitatively and qualitatively validate the reconstruction performance of CSR in real-world scenes. CSR achieves centimeter-level accuracy commensurate with established LiDAR-based methods, concur- rently boosting efficiency and reducing resource expenditure.