Aerodynamic Analysis, Dynamic Modeling, and Control of a Morphing Aircraft

In this paper, a longitudinal dynamic model of a variable-sweep-wing morphing aircraft is proposed based on the Firebee unmanned aerial vehicle (UAV), accounting for changes in aerodynamic and inertial properties. Wing geometries and aerodynamic performance are also analyzed in six morphing configurations. The eigenvalues, damping, and frequency are investigated within short-period and phugoid modes. In addition, a classic proportional-integral-derivative (PID) controller is designed with different gains according to six morphing configurations. In three degrees of freedom (DOF) nonlinear simulations, the morphing aircraft maintains a straight and level flight in dash configuration at first and then changes to a loiter configuration at a fast and slow morphing rate. Except for the morphing moment caused by wing gravity, other morphing forces and moments can be ignored. Simulation results show that the designed controller works well with good trajectory-tracking performance, and a larger morphing rate leads to greater magnitudes in attitude, velocity, and altitude variations.