Safety flight control for aggressive maneuvering of unmanned autonomous helicopters under multi-class and multi-type constraints

To address the Safety Flight Control (SFC) problem of aggressive maneuvering for Unmanned Autonomous Helicopters (UAH) under multi-constraint coupling environments, this study proposes a coordinated SFC strategy for multiple-type constraints under interval-type and norm-type dual-mode constraints, building upon the advantages of interval constraint processing. By designing a class of saturation-like smooth functions, the proposed method achieves smooth transition of commands at interval constraint boundaries, while constructing quadratic boundaries in norm space to fundamentally expand constraint processing dimensions and effectively alleviate the negative impacts of control saturation on closed-loop stability. Furthermore, a multi-constraint coordination mechanism based on dynamic priority scheduling is established to eliminate the influence of command limitation on closed-loop stability. On this basis, a hierarchical control architecture is constructed to realize decoupled design of position loop and attitude loop. Using such methods as input-to-state stability, closed-loop invariant sets, and Lyapunov functions, the controller parameter design is systematically summarized along with the stability, safety, and steady-state tracking performance of UAH closed-loop systems. Finally, the effectiveness of the proposed strategy is verified through a full-scale nonlinear model of a medium-sized UAH.