A ship high-precision positioning method in the lock chamber based on LiDAR

Accurate perception of ship position can assist ships in safe navigation in the lock. However, due to the limited space in the lock chamber, the satellite positioning signal is unstable, making it difficult to accurately position the ship in real time. Therefore, a novel ship positioning method based on LiDAR is proposed. Firstly, the preprocessing of point cloud is realized through the steps including point cloud reflection intensity filtering, coordinate transformation, and ship point cloud clustering extraction. Then, different segmentation strategies are proposed to extract the point cloud of each ship with respect to the characteristics of point cloud changes during the ship's navigation upstream and downstream through the lock. Finally, real-time tracking of ships is realized by Kalman filter. The experiments of four ships navigating upstream and downstream through the lock were conducted respectively. The results show that the root mean square error (RMSE) of ship position is about 1 m, which is better than the BeiDou positioning accuracy. The overall processing time of each frame is controlled within 0.1 s, which meets the practical requirements. This present study provides a new solution to the ship positioning problem in locks. •A point cloud preprocessing method is established.•A point cloud segmentation strategy is proposed.•The experiments were conducted with four ships navigating upstream and downstream through the lock.•The proposed method can realize the real-time accurate positioning of each ship.