Coverage path planning for harbour seabed surveys using an autonomous underwater vehicle

This paper considers offline algorithms for pre-mission path planning to achieve coverage of the seabed of a complex but well-characterised planar area using an autonomous underwater vehicle fitted with side-looking sonar. The vehicle can swim over terrain at constant altitude, but must follow a path constructed from straight line segments. Imagery collected during turns is not used. This paper discusses the preparation of boundaries for the survey area, the introduction of buffer zones for safety of vehicle navigation, the decomposition of the surveyable area into subareas using an approximation to the generalised Voronoi diagram, calculation of paths within sub-areas that allow for incomplete sonar coverage, and connection of sub-area paths with transits to obtain a mission plan.