## 3 Algorithm Design: Hybrid Voronoi-A* Framework and Pseudocode
However, this method exhibits the following three inherent limitations: (1) it cannot guarantee distance-optimal routes due to discrete DEM-based path planning, particularly in complex terrain; (2) its dependency on pre-existing DEM data restricts deployment in unmapped or dynamically changing environments; (3) the static environment assumption provides no inherent capability to handle unexpected obstacles such as complex weather conditions. ## 6 Future Research

Our preliminary validation in simulation environment has demonstrated the algorithm's effectiveness, and our next step will involve deploying the proposed algorithm to ground control stations in order to command UAVs in mountainous terrain. Through the collection of real flight data, we will further validate the algorithm's adaptability. Additionally, we plan to enhance global planning trajectories by integrating comprehensive environmental information from sensors and data links to advance research on dynamic obstacle avoidance algorithms. For instance, we will explore incorporating local-range mechanisms, such as the APF and Deep Q-Network (DQN), to enable dynamic obstacle avoidance and trajectory replanning. Furthermore, we aim to generalize the framework by modularizing the A* algorithm (used for route segment connection) and implementing it as one of several selectable algorithms (Dijkstra, PRM, APF, etc.). This modular approach will allow for combinatorial testing to improve applicability across diverse flight scenarios. Conceptualization, B.D. and P.Y. ; methodology, B.D. ; resources, B.D. ; software, Y.Y. and S.L. ; supervision, G.Z. ; validation, Y.Y. ; writing--original draft, B.D. ; writing--review and editing, G.Z., P.Y. and S.L. All authors have read and agreed to the published version of the manuscript. This research received no external funding. The data presented in this study are available upon request from the corresponding author due to proprietary constraints related to ongoing product development under institutional intellectual property agreements. Author [PERSON], [PERSON], [PERSON] are employed by AVIC Aviation Electronics Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. ## References

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