A Dual-Layer Event-Triggered Framework for Distributed UAV Swarm Control

The event-triggered synchronization problem for six-degree-of-freedom fixed-wing multiple unmanned aerial vehicles (UAVs) over a directed spanning tree topology is addressed in this work. The primary challenges lie in handling intermittent neighboring state information caused by event-triggered communication. To address this limitation, a smooth auxiliary function is designed to ensure a smooth transition to the triggered value within each triggering interval by updating the maximum state rate. The first-order distributed estimator incorporating the smooth function is directly applied to the backstepping framework for rotational dynamics, guaranteeing the differentiability of the virtual control law. Compared to state-of-the-art methods, the proposed estimator features a lower order and exhibits stronger adaptability to track leader UAV's speed and attitude angles that are either aperiodic or non-zero constant. Additionally, a sign-independent compensation mechanism enhances control accuracy. The proposed method is validated through semi-physical simulation.