Robust nonlinear adaptive backstepping controller design for unmanned autonomous vehicles

Abstract

A robust nonlinear adaptive controller design for unmanned autonomous vehicles (UAVs) for controlling the hovering flight is presented. The controller is premeditated recursively based on the control Lyapunov theory where the mass of the UAV in the model is considered as anonymous parameter. To illustrate the forcefulness property of the designed controller, the effects of external disturbances are also considered in the UAV dynamical model throughout the devise of the controller. The unknown parameter (mass) is estimated using the adaptation law and incorporated in the final control law and then the overall immovability of the UAV system is confirmed by forming the negative semi-definiteness of Lyapunov functions. Note that the designed controller is adaptive to the mysterious parameter of the UAV and robust to external disturbances. Finally, the designed controller performance is experienced using a MATLAB simulation model under hovering flight condition and the performance is also compared with an existing nonlinear robust adaptive backstepping controller. The simulation results illustrate the sturdiness of the designed controller as compared to the existing nonlinear robust controller in terms of declining exterior wind gusts.