Robust trajectory tracking for unmanned aircraft systems using high order sliding mode controllers-observers

This article deals with the design of a novel algorithm that combines a Modified Super-Twisting Controller with a High Order Sliding Mode Observer to enable an aerial vehicle to track a trajectory under the assumption that i) its translational velocities are unavailable and ii) there are unmodeled dynamics and external disturbances. We present a mathematical justification that ensures the existence of a second-order sliding motion for the combination ControllerObserver. In order to demonstrate the effectiveness of the proposed solutions, a set of simulation results are presented.