An improved RRT algorithm based on prior AIS information and DP compression for ship path planning

The slow convergence, excessive turning points and non-smooth path generation are significant challenges in ship path planning by existing RRT-related algorithms. To address these issues, this paper proposes a novel approach called PI-DP-RRT, which combines prior automatic identification system (AIS) information and Douglas-Peucker (DP) compression for ship path planning. Firstly, we cluster the available AIS data to construct guide regions, the guidance region can provide information to guide the target in the RRT algorithm. Next, we improve the algorithm's sampling strategy based on the guide region by using paranoid sampling, which increases convergence rate. Finally, we optimize the path by applying the improved DP algorithm and a new path optimization method to enhance its smoothness and practicability. Comparative simulation experiments are conducted in real scenarios and challenging environments. The results indicate that the proposed PI-DP-RRT algorithm outperforms other RRT-related algorithms in terms of efficiency, achieving a good balance between algorithm efficiency and accuracy. The planned path reduces the turning range and improves the smoothness of the path, which promotes the safety and efficiency of ship navigation.