Integrated Guidance Law for Target Tracking and Obstacle Avoidance in Fixed-wing UAVs Based on Composite System Theory

The cooperative tracking of moving ground targets in obstacle environments by multiple fixed-wing Unmanned Aerial Vehicles (UAVs) has broad applications in both military and civilian fields. While extensive research has focused on tracking guidance laws and obstacle avoidance methods, existing approaches typically treat these functions separately. In contrast, this paper proposes a unified guidance design method that simultaneously addresses both target tracking and obstacle avoidance. The method develops a three-dimensional guidance strategy for fixed-wing UAVs under maneuvering constraints, considering the coupling of linear and angular velocities during cooperative tracking and obstacle avoidance. Comprehensive stability theory proofs are provided to ensure global asymptotic stability for the proposed method. To evaluate the effectiveness of the guidance law, simulations were conducted, including a comparative study with the artificial potential field method, where the proposed approach demonstrated superior robustness and coordination. Additionally, six-degree-of-freedom (6-DOF) simulations validated the applicability of the guidance law under realistic UAV dynamics, showing strong adaptability and realtime responsiveness.