Abstract:To address the dual challenges of navigating complex obstacles and managing communication constraints during high-speed, near-ground flight of large-inertia rotor UAVs, this paper proposes an autonomous obstacle avoidance method based on improved navigation map construction and trajectory planning. First, an enhanced mapping strategy integrating the Euclidean Signed Distance Field (ESDF) and OctoMap is developed to satisfy the environmental representation requirements for both global search and local optimization. Subsequently, an improved Batch Informed Trees (BIT*) algorithm is employed for global path search, while B-spline interpolation is utilized for local trajectory refinement. Dynamic constraints, smoothness requirements, and tracking accuracy are embedded within the optimization process to ensure the generated trajectory is trackable for the large-inertia rotor UAV platform. Simulation experiments conducted in the Gazebo environment validate the mapping and navigation capabilities of the proposed algorithm. The results demonstrate that, compared to traditional path planning methods, the average planning speed is improved by approximately 31%, and the obstacle avoidance success rate reaches 100% across ten trials. Furthermore, outdoor flight experiments in a real-world environment confirm the feasibility and practical effectiveness of the algorithm.