Online motion planning for underwater inspection

This paper proposes the use of path planning algorithms for AUVs in applications where the robot needs to adapt online its trajectory for inspection or safety purposes. These algorithms generate trajectories under motion constraints, which can be followed without deviations, to ensure the safety even when passing close to obstacles. View planning algorithms are also combined to decide the movements to be executed to discover the unexplored seabed or target and to cover it with a camera or sonar. Online mapping with profiling sonars and online planning with fast sampling-based algorithms, allows the execution of missions without any previous knowledge of the 3D shape of the environment. Real 2D results with a torpedo-shaped AUV with hovering capabilities in an artificial harbour structure and natural rocky canyon demonstrate the feasibility of the approach for avoiding or inspecting the underwater environment. Simulated 3D results also show the capability of the approach to be extended in more real and challenging environments.