The design of the four rotor unmanned aircraft control algorithm

For Qball-X4 four-rotor unmanned aircraft with its own characteristics, creating nonlinear model of system and adopting double closed-loop control algorithm with inner and outer loop are controlled by attitude and position respectively. Linear quadratic regulator is easy to solve state feedback control rate quickly, and has good robustness, thus LQR is utilized to design attitude inner loop controller. Due to the PID control algorithm has simple structure, strong robustness, thus PID is utilized to design position loop controller. Utilize Matlab/Simulink and flight test to verify control algorithm, and the result shows that the control algorithm can successfully achieve the hovering control, and achieve good control effect.