Research On Flight Control Technology Of The Receiver Aircraft In Probe-and-Drogue Autonomous Aerial Refueling

Aerial refueling technology is playing a very important role in the modern warfare. It canincrease the flight range, cruising duration and payload of the receiver aircraft. This thesis has studiedthe flight control problem of receiver aircraft during docking and tracking phases in theprobe-and-drogue autonomous aerial refueling.First of all, the research focused on the analysis of characteristics and existing main disturbancesin probe-and-drogue autonomous aerial refueling. Several important mathematical models wereestablished in the paper, such as the dynamics model of the receiver, tail vortex field model, thedynamic characteristic model of refueling drogue and atmospheric turbulence model, which had laid asolid foundation for the design of related controllers.Secondly, the docking and tracking controller of receiver aircraft was designed on the basis ofreference observer. The relative position between the receiving probe and refueling drogue wasmeasured and calculated by relative navigation system. In order to realize the smooth tracking anddocking of receiver aircraft, a reference trajectory generation module was designed for calculatingexpected trajectory of receiver aircraft at real-time. The expected state variable and control variablewere estimated according to the real-time observer of receiver aircraft. A full state feedback controllerwas designed for controlling the receiving probe to track the refueling drogue and realize the dockingand keeping the relative position.Thirdly, in order to improve docking and tracking performances in the refueling situation ofuncertain disturbances and actuator failures, the model reference adaptive control method was usedfor the design of docking and tracking controller. A docking and tracking controller based on L1adaptive control was proposed in this foundation, which assured the rapid adaptability of thecontroller and improved tracking performance, stability, and robustness of the closed-loop system.Finally, a flight control simulation system of the receiver aircraft in probe-and-drogueautonomous aerial refueling was established in the numerical simulation environment of MATLAB.The designed docking and tracking controllers of the receiver aircraft were simulated separately andcompared with each other under disturbances of different atmospheric turbulence, tail vortex effect,control failure and other uncertain factors.The simulation results indicate that the designed docking and tracking controllers can realize theaccurate docking and tracking maneuver between the receiving probe and refueling drogue in different aerial refueling disturbance environment. Especially, the docking and tracking controllerbased on L1adaptive control has greatly enhanced the system’s dynamic property and robustness. Theresearch results have provided the theoretical basis for future realization of the autonomous aerialrefueling in our country.