Development of a Bearing-Based Distributed Control Method for UAV Formation Tracking and Obstacle Avoidance

Unmanned Aerial Vehicles (UAVs) are playing an increasingly vital role in modern battlefields. Accordingly, considerable research has been devoted to Manned–Unmanned Teaming (MUM-T) systems, with formation flight recognized as a key enabling technology for coordinating multiple UAVs. In MUM-T operations, leader–follower formations are commonly employed, while distributed formation methods have gained increasing attention owing to their stability and scalability. Among these, bearing-based control provides unique advantages for managing dynamic formations involving scaling and rotation. However, conventional bearing-based approaches typically require multiple leaders and encounter inherent limitations in flexibly handling obstacle avoidance. To address these challenges, this study proposes a hierarchical bearing-based leader–follower formation system comprising a single leader and multiple follower UAVs. By introducing the concept of virtual leaders, the proposed method enables the construction of formations with only one leader, thereby simplifying the system architecture while preserving scalability. In addition, a novel obstacle-avoidance strategy is developed, allowing followers to avoid collisions efficiently while maintaining formation integrity. The effectiveness of the proposed framework is demonstrated through numerical simulations of representative formation patterns, including V-shaped and hexagonal configurations, in obstacle-rich environments. The results confirm that follower UAVs successfully tracked the leader, preserved the designated formation, and achieved effective obstacle avoidance, thereby validating the stability and robustness of the proposed approach.