LAUSR

Abstract The quadcopter is one of the most used unmanned aerial vehicles in both military and commercial in- and outdoor applications. In this study, the problem of UAV attitude control is investigated when there are discrepancies in the characteristics of the 4 actuators, i.e., electrical motors and propellers. To tackle this problem in a simple way, a cascade control strategy is proposed with a PD controller in the inner loop to achieve stabilization, and PI controller in the outer loop to ensure disturbance rejection. This way, the external disturbance created by the actuator asymmetry is compensated by the PI loop. The robustness of the control strategy is tested in simulation as well as in real-life tests on a 1-DOF test bed.