Bi-Directional Adaptive A* Algorithm Toward Optimal Path Planning for Large-Scale UAV Under Multi-Constraints

For large-scale Unmanned Aerial Vehicle (UAV), it is a challenging problem to automatically generate an optimal path considering the multi-constraints. In order to improve the efficiency and optimality of conventional A* algorithm, Bi-directional adaptive A* algorithm is proposed in this paper. Regarding to the defect of expansion efficiency for conventional A* algorithm based on multi-direction, directional search strategy is adopted to improve the efficiency of expansion process and guarantee the smooth of the path. Adaptive step strategy and adaptive weight strategy are used to improve the exploration speed and the accuracy of the proposed algorithm. By adopting bi-directional search strategy, the exploration ability of the algorithm can be improved in some complex environment. Finally, rewiring process is introduced to optimize the path length. The simulation for UAV path planning under the multi-constraints conditions is carried out and the simulation results show that Bi-directional adaptive A* algorithm has the superiority in run time and path quality.