Guidance and control method for dynamic net-recovery of UAV and the flight test verification

This study focuses on the guidance and control technology for shipborne fixed-wing unmanned aerial vehicle (UAV) during dynamic recovery. The guidance system for precise recovery based on a segmented control strategy is proposed. The scheme design and integration test of the system for dynamic net-recovery are completed. Online recovery route planning is achieved by predicting contact time through a numerical iteration method, while a nonlinear guidance algorithm based on guidance points is employed for accurate mid-phase tracking. Based on the classical proportional guidance and the longitudinal/lateral decoupling strategy, a three-dimensional terminal guidance law is designed to achieve accurate control of the impact point in the terminal guidance phase of dynamic recovery. The effectiveness of the segmented guidance strategy with the algorithm in each phase is proved through simulation and flight tests. The results show that the recovery route planning method is simple, effective and adaptable. The tracking deviation of the guidance algorithm for the route is less than 0.5 m, and the steady-state accuracy of altitude control is better than 0.5 m. The terminal guidance accuracy of UAV in the dynamic net-recovery test is better than 0.8 m. The guidance and control accuracy throughout all phases meets UAV net-recovery requirements, making the proposed method suitable for engineering applications.