A hierarchical global path planning approach for AUV

Proposes a hierarchical global path planning approach for an autonomous underwater vehicle in an ocean. This approach consists of successive decomposition of the robot´s workspace and searching for a path at each level of decomposition. In the process of heuristic search, the evaluation function takes into account both the energy cost and the length of paths. The approach proves to be flexible and practicable, and can reduce memory consumption significantly.