Saturation-predictable prescribed performance hierarchical control for fly-around formation via secure distributed and edge-based event-triggered mechanisms

In multiple-spacecraft fly-around observation of noncooperative targets, delayed leader information, false data injection (FDI) attacks, disturbance propagation, limited communication, and input saturation jointly threaten formation rigidity and prescribed performance feasibility. This paper develops a saturation-predictive prescribed performance hierarchical control framework with secure event-triggered estimation and edge-triggered cooperative tracking. In the upper layer, an event-triggered secure leader observer is constructed, where a dynamic multi-reservoir echo state network (DMESN) with online minimum-parameter learning compensates leader-state delays, and a mechanism based on confidence factors isolates links contaminated by FDI attacks to recover a safe topology. Based on the recovered topology, an edge-based event-triggered prescribed performance controller generates virtual commands to preserve formation rigidity while reducing continuous neighbor monitoring. In the lower layer, an extended state observer based on DMESN estimates lumped disturbances, and a saturation-predictive prescribed performance controller expands the performance boundary in advance to avoid singularity risks caused by input saturation. Theoretical analysis establishes closed-loop stability, and numerical simulations together with air-bearing robot experiments demonstrate the effectiveness of the proposed method.