Admittance control of quadrotor UAV-environment interaction with actuator saturation

Abstract

This study proposes an anti-saturation fixed-time sliding mode control algorithm based on admittance control to address quadrotor UAV-environment interaction subject to actuator saturation. Under admittance control, the UAV is controlled to achieve a compliant behavior in the presence of unknown excessive disturbances from the environment. These disturbances are estimated by using an adaptive fixed-time integral sliding mode disturbance observer that does not require the upper bound information of unknown disturbances. To enhance trajectory tracking performance subject to actuator saturation, an anti-saturation fixed-time sliding mode controller integrating an auxiliary dynamics system is presented to tackle the effect of actuator saturation. Finally, the superiority and effectiveness of the proposed controller are demonstrated through comparative analysis with other controllers.