Dynamic Modeling And Control Of The Motion Of The Hose-Drogue

Aerial refueling can extend the flight endurance, range and increase the payload of the aircrafts.The refueling drogue in Probe-Drogue Refueling exhibits unstable motion because of the disturbed airflow. To restrain the shaking motion of the Hose-Drogue, decreasing the difficulty of coupling with a refueling drogue for a receiver aircraft safely and accurately, the research on the dynamic modeling and control of the motion of the Hose-Drogue is conducted.First of all, the kinematics and dynamics analysis of the hose are carried out according to the model of the multi-link system. Then the calculation of the aerodynamic load on the hose and drogue are introduced respectively. The dynamic model of the shaking motion of the aerial refueling Hose-Drogue is built by adding the dynamic model of the controllable drogue to the model of rigid multibody dynamics. Then the whole numerical simulation process of the dynamic model of the motion of the Hose-Drogue is presented.Secondly, the kinetic characteristics of the Hose-Drogue due to the disturbed airflow are simulated and analyzed. The tanker wake model, atmospheric turbulence model, and the bow wave of the receiver aircraft model are built orderly. The kinetic characteristic of the Hose-Drogue due to the atmospheric turbulence, the tanker wake effect, and the bow wave effect are simulated and analyzed respectively.Thirdly, based on the LQR optimal control method, the controller of the controllable drogue is designed. To restrain the shaking motion of the Hose-Drogue, the no-linear model of the motion of the Hose-Drogue is linearized and reduced to design the LQR controller according to the optimal control theory. Then the simulation of the motion of the Hose-drogue with the control system disturbed by the atmospheric turbulence, the bow wave, and the comprehensive turbulence of both are conducted respectively, the simulation results show the effectiveness of the restriction to the shaking motion of the Hose-Drogue.Finally, the computation of the effective wind components and gradients on the receiver aircraft suffered by the tanker wake is introduced, then the no-linear model of the receiver aircraft in the tanker wake flow field is built, and the LQR controller for the receiver aircraft is designed to achieve a successful aerial refueling. A MATLAB/SIMULINK based simulation environment by integrating the Hose-Drogue control system, the receiver aircraft control system, and the disturbed airflow module has been developed to simulate the docking stage of autonomous aerial refueling, and thesimulation results show that the control to the motion of the Hose-Drogue could reduce the difficulty of aerial refueling docking enhancing the security and the efficiency of autonomous aerial refueling.