This article addresses a guidance and control strategy for an unmanned surface vehicle subject to uncertainties. The controller uses a dynamic three-degree-of-freedom model with identified parameters of an experimental platform. A strategy based on adaptive sliding-mode control is designed for the motion control of surge speed and heading variables, whereas a line-of-sight guidance law, with time-varying look-ahead distance, is applied to achieve path following. The adaptive controller is robust against bounded uncertainties/disturbances, and it does not overestimate the control gain. Outdoor experimental results validate the performance and advantages of the proposed control scheme in three different scenarios: 1) set-point regulation; 2) tracking of time-varying references; and 3) path following. To further demonstrate the characteristics of the proposed controller, a comparison against a standard controller while carrying an extra payload of 20% of the mass of the vessel is included.

A novel control scheme for the regulation and trajectory tracking in spite of external perturbations of the three degrees of freedom (3-DOF) helicopter is presented. The scheme allows reduced control effort, vibration reduction, and accurate tracking. The proposed approach combines a continuous differentiator with an adaptive super twisting controller. The differentiator provides state estimation, whereas the adaptive super twisting algorithm is chosen such that the gains of the controller are adapted to reduce the control effort and do not require the knowledge of the bounds of the uncertainties and perturbations. Furthermore, finite time convergence of the continuous differentiator to a neighborhood of the desired trajectory, allows to design independently controller and the differentiator, satisfying the principle of separation. Finally, the proposed control scheme is validated by experimental tests under external disturbances.