Ship path planning is crucial for the shipping industry, especially for the development of autonomous ships. Many algorithms have been developed over the last few decades to solve the ship path planning problem. However, it is still challenging for ship path planning in an inland waterway. In this paper, an improved RRT algorithm for ship path planning in complex inland waterways is proposed. The improved algorithm has a path shearing and smoothing module, and the function of keeping a safe distance between a moving ship and obstacles. In addition, the algorithm has been tested in two inland waterway scenarios, and the results have confirmed its feasibility and reliability. The path planning algorithm proposed in this research seeks to reduce the risks faced by ship navigation in inland water. It has theoretical and practical significance in improving navigation safety in complex inland waters.

The shipping volume in inland waterways has been rapidly increasing in recent years. However, it is still challenging to trace oil spills caused by maritime accidents. In this study, the oil spill dispersion trajectory in inland rivers was obtained by simulating the trajectory of oil particles under different waterway conditions based on a simulated flow field. Firstly, the flow field was simulated using a volume of fluid (VOF) model and the solution of an open-channel equation. Then, an oil particle diffusion and drift model was established using Python to simulate the diffusion of the oil. Finally, eight oil spill simulation scenarios were conducted with different channel shapes and cross-sections. The results showed that oil spills spread more extensively in a curved channel with a trapezoidal cross-section compared to other channel shapes and cross-sections. The findings of this research could be used to guide inland river environmental protection and oil spill trajectory tracking.