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A Safe Maritime Path Planning Fusion Algorithm for USVs Based on Reinforcement Learning A* and LSTM-Enhanced DWA
Zhenxing Zhang1, Qiujie Wang2, Xiaohui Wang2
1School of Computer Science and Technology, Zhejiang University of Science and Technology, Hangzhou 310023, China.
This study introduces a hybrid path planning method for Unmanned Surface Vehicles (USVs) using reinforcement learning and an improved Dynamic Window Approach (DWA). The approach enhances safety and trajectory smoothness in complex maritime environments.
Area of Science:
- Maritime Robotics
- Artificial Intelligence
- Path Planning Algorithms
Background:
- Path planning for Unmanned Surface Vehicles (USVs) in dynamic maritime environments presents significant safety challenges.
- Existing methods struggle with predictability and trajectory smoothness when encountering dynamic obstacles.
Purpose of the Study:
- To develop a reliable hybrid path planning approach for USVs.
- To improve the safety, predictability, and smoothness of USV trajectories in complex marine settings.
Main Methods:
- A hybrid approach combining a reinforcement learning-enhanced A* algorithm and an improved Dynamic Window Approach (DWA).
- A* algorithm enhancements include dynamic neighborhood search, adaptive weighting, and path post-optimization.
- Dynamic obstacle prediction uses a Kalman Filter (KF) integrated with a Long Short-Term Memory (LSTM) network.
- DWA incorporates International Regulations for Preventing Collisions at Sea (COLREGs) for compliant navigation.
Main Results:
- The enhanced A* algorithm demonstrated better adherence to USV kinematic models.
- The improved DWA significantly reduced collision risks in simulations.
- The hybrid approach resulted in shorter path lengths and smoother trajectories.
Conclusions:
- The proposed hybrid path planning method enhances USV navigation safety and efficiency.
- The integration of RL, KF-LSTM, and COLREGs provides a robust solution for dynamic maritime environments.
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