Attitude Control of UAV based on PI Dynamic Inversion

The nominal dynamic inversion control system, whose pseudo-inverse controller only contains a proportional, has the steady-state error because of the inaccuracy model or the change of plant. A Proportional-Integral (PI) dynamic inversion controller is designed to control the attitude of Unmanned Aerial Vehicle (UAV) and cancel the steady-state errors of outputs in this paper. First, according to the time-scale separation principle, the attitude control system is divided into the outer loop which is employed to track the orientation angles and the inner loop which is employed to control the angular rates. Next, the flight controllers based on PI dynamic inversion are applied to the inner and outer loops simultaneously. Then, the controller parameter choice principle based on the Routh-Hurwitz Criterion and the bandwidth limit of the time-scale separation principle is introduced. Finally, considering multiple uncertainties, the proposed approach is applied to the attitude control of a certain UAV. Simulation results show the effectiveness and robustness of the control approach.