Adaptive tracking control of quadrotor UAV system with input constraints

In this paper, sliding mode control (SMC) and adaptive tracking control are given to perform the position and attitude control of quadrotor unmanned aerial vehicle (UAV) model. For the double closed-loop control system, SMC is used in the inner loop position subsystem control. In the inner loop subsystem, the virtual attitude angles of attitude subsystem tracking control are calculated. The adaptive tracking control is applied in the outer loop attitude subsystem control with input saturation constraints. Subsequently, the auxiliary design system is introduced to analyze the impact of input constraint, and its states are used for adaptive tracking control design. Then, the internal uncertainties and the external disturbances will be observed and compensated by extended state observer (ESO). Finally, simulation studies are presented to illustrate the effectiveness of the proposed SMC and adaptive tracking control.