Summary This paper proposes an adaptive controller for the trajectory tracking problem of vertical take‐off and landing unmanned aerial vehicles with unknown inertia and gyro‐bias, in the presence of external disturbances and actuator loss of effectiveness. To achieve our control objective, first, an a priori bounded virtual control law, providing an a priori bounded thrust and desired attitude, is designed for the translational dynamics. Thereafter, the torque input is designed for the rotational dynamics to track the desired orientation derived in the first stage. The stability of the overall hierarchical closed‐loop system and the global convergence of the tracking errors to zero are rigorously established. Finally, numerical simulations are performed to validate the effectiveness of the proposed control scheme.

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In this paper, we develop a control law for Functional Electrical Stimulation (FES) application fields. This work aims to command the knee joint movement of patients in the seated position suffering from neurological disorders that lead to a partial or total paralysis of the limb. For this purpose, we propose the synthesis of an adaptive continuous control that permits to the knee joint the tracking of a time-varying desired angle. The knee movement is represented by the dynamical model of the lower limb. The designed control ensures an asymptotic stability while considering constraints such as unknown model parameters, unknown perturbation effects and unknown spasticity and fatigue parameters. The applicability and the effectiveness of the designed control law are shown through the simulation results.