ZHANG Caili, XIANG Longgang, LI Yali, WANG Limei, HOU Shaoyang, YU Qian
[Objectives] The setting of lane-turning signs at planar intersections is a critical measure to achieve orderly vehicle flow on a large scale. These signs not only assist traffic management authorities in controlling traffic at planar intersections, but also help drivers avoid detours caused by selecting the wrong lane. Therefore, lane-level turning relationships provide crucial information for precise navigation services. Setting turning signs at intersection lanes is a fundamental aspect of traffic management that promotes safety, orderliness, and efficiency. Considering the low cost and fast updates possible with crowd-sourced trajectories, this paper presents a study on the recognition of lane-level turning relationships at planar intersections using crowd-sourced data. [Methods] First, the intersection lane space was determined. Road network topology processing, trajectory data cleaning, and map matching were performed to establish connections between trajectory points and their corresponding road segments. Based on processed road network and trajectory data, trajectories within the intersection guide area were extracted, and noise was removed from multiple perspectives. Using a Gaussian mixture model, cluster analysis was then conducted to detect lane information at road segment intersections. Second, intersection lane noise turnings were removed. Horizontal and vertical statistics of lane turning trajectories were analyzed, and trajectories falling below the threshold were identified as noise turnings and removed. Finally, intersection lane-turning identification rules were designed, taking into account the distribution of different lane-turning trajectories. An unsupervised classification method was used to detect lane-turning information based on these rules. [Results] To validate the effectiveness of the method, we selected OpenStreetMap road networks and crowd-sourced trajectories from two areas in Beijing for experiments, focusing on 10 representative intersections on major city thoroughfares. The main findings are as follows: (1) Based on the original trajectory data, lane-level turning relationships were identified using one-day trajectories, peak period trajectories, and off-peak trajectories, with recognition accuracy rates of 74.3%, 72.7%, and 55.7%, respectively; (2) After data encryption and simplification, recognition accuracy gradually improved with increased sampling frequency, reaching a maximum of 77.0% with 3-second encryption; (3) The proposed method demonstrated advantages over the threshold segmentation method, the method without noise turning elimination, and the topological connection method. [Conclusions] This research on lane-level turn relationship recognition based on crowd-sourced trajectories has significant implications for intelligent transportation and autonomous driving. The algorithms, technologies, and research findings in this paper provide a valuable reference for future research and foster continued innovation and application of intelligent transportation systems.