Abstract:

Three-dimensional terrain scenes typically possess complex and diverse environment along with jagged terrain features， which poses challenges to path planning. To address this issue， in this paper a highly reliable path planning approach under the influence of non-topographic fluid characteristics and three-dimensional complex terrain is proposed. This method encompasses initial global path planning， path inspection， and re-planning under 3D terrain. For the initial global path， an AHTR algorithm that combines the advantages of Hybrid A* and Theta* is proposed. This algorithm enhances the inter-node sampling and detection methods in accordance with the traits of the 3D terrain scene and introduces in a terrain risk assessment function.to plan a path for the vehicle that can evade rough terrain and comply with kinematic constraints. For path inspection， the path risk test function is designed based on the results of vehicle dynamics analysis considering the characteristics of non-terrestrial fluid， and the impact of non-terrestrial fluid characteristics on path planning is verified. For path re-planning， an enhanced AHTR algorithm is proposed， which takes into account of both 3D terrain features and non-terrain fluid features to guarantee that the planned path can effectively avoid risks. Simulation experiments demonstrate that compared with Hybrid A* and Theta*， the intensity of ground undulation in the path planned by the AHTR algorithm is decreased by 26.54% and 49.04%， with the average pitch angle of the vehicle reduced by 44.39% and 69.40%， the path risk lowered by 26.32% and 41.67%， and the final path safety improved by 58.06% and 88.46%， which effectively ensures path reliability.

Key words: 3D terrains, non-topographic fluid, path risk, global path planning, local path re-planning