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An improved A* algorithm for generating four-track trajectory planning to adapt to longitudinal rugged terrain.
Zhi-Guang Liu1, Hai-Nan Yang1, Qin-Cong Wang1
1School of Control and Mechanical Engineering, Tianjin Chengjian University, Tianjin, 300384, China.
Scientific Reports
|February 25, 2025
Summary
This study introduces an improved A* algorithm for a four-wheeled robot to navigate rough terrain by planning paths through longitudinal trenches. The method ensures safe traversal by considering chassis height and roll angle, enabling effective rough terrain navigation.
Area of Science:
- Robotics
- Artificial Intelligence
- Path Planning
Background:
- Autonomous robots require robust navigation in unstructured environments.
- Traversing complex terrains like longitudinal trenches poses significant challenges for wheeled robots.
Purpose of the Study:
- To develop a trajectory planning method for a four-wheeled robot to navigate longitudinal trenches.
- To enhance path planning algorithms for safe and efficient movement in rough terrain.
Main Methods:
- A grid map representing longitudinal trench terrain was created.
- An improved A* algorithm was developed, incorporating robot dimensions and safety constraints (chassis height, roll angle).
- The algorithm plans simultaneous four-wheel straddling paths through ditches.
Main Results:
- Simulation and experimental validation confirmed the method's effectiveness in planning paths for complex terrain.
- The planned path's adaptability to target distance, ground clearance, and roll angle was demonstrated.
- The robot successfully crossed a 10.5m longitudinal ditch in 19.8s at 0.53m/s with a tilt angle under 20°.
Conclusions:
- The improved A* algorithm enables effective and safe path planning for four-wheeled robots in longitudinal trenches.
- The method prioritizes speed and safety, allowing for dynamic path adjustments based on environmental and robot-specific parameters.
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