Prop-hanging control of a thrust vector vehicle with hybrid Nonlinear Dynamic Inversion method

Abstract

The prop-hanging control of the fixed-wing aircraft can enable the vehicle to improve the cruise performance and hover ability. The prop-hanging control of the thrust vector vehicle would be a challenging problem, for the reason that it is a system with properties of inherent instability, coupling, non-linearity and non-minimum phase characteristics. To deal with these complex problems, a hybrid Nonlinear Dynamic Inversion (NDI) method is proposed in this paper. Inspired by NDI, Incremental NDI and angular acceleration feedback control methods, the hybrid NDI method includes three parts: feedforward control, proportional control and logical integral control, which can enable the system to have a rapid response in the transient phase and a satisfactory performance in the steady state. A numerical simulation is conducted to test the performance and the robustness of the proposed control method, and a Hardware-in-the-loop simulation is also conducted to check the practicability and effectiveness in the actual application. Simulation results show that the proposed control method can effectively improve system robustness and is practical.