Modeling, simulation, analysis and control of close formation flight

Abstract

This paper focuses on the aerodynamic characteristics of aircraft close formation flight. The formation model for small unmanned aircraft is studied, and the disturbance of the wake induced velocity generated by the leader aircraft on the tail aircraft is analyzed. It is found that the lead aircraft has a significant effect on the lift and drag of the tail aircraft. It is also demonstrated that the aerodynamic characteristics of the tail plane can be improved when the following plane is in the proper position of the leader in formation flight. Precise position control of the tail plane in general flight operations is achieved under the influence of the tail vortex. Firstly, a model for the wake vortex of the leader was established, and then computational fluid dynamics(CFD) software was used to simulate the two unmanned aerial vehicles (UAVs) to verify the accuracy of the model. A control algorithm was designed to realize the stability of formation flight. Mathematical simulation and validation were performed. The designed control law is able to keep the tail plane in the appropriate position in the formation flight so that the tail plane is subjected to the maximum lift.