Development of a Method for Synthesizing Disturbance Identification Systems for Unmanned Aerial Vehicles

Abstract

This paper proposes a method for synthesizing a disturbance identification system for quadcopter-type unmanned aerial vehicles (UAVs) that allows determining the magnitudes of force and moment disturbances acting on all degrees of freedom of the UAV and caused by the uncertainty of the parameters and the presence of unknown external influences. We present a complete mathematical description of the UAV dynamics and kinematics taking into account the aerodynamic drag, as well as the uncertainties of the parameters and the influence of the environment, which are represented in the dynamic equations by additive unknown functions which are subject to estimation. To determine the values of these unknown functions in real time, sliding mode observers are proposed. The disturbance data can then be used by adaptive control systems to compensate for their negative effects and improve the accuracy of motion. Numerical simulation is performed, the results of which confirm the operability and effectiveness of the proposed solutions. The efficiency and accuracy of observer estimates are illustrated for several scenarios, including the movement of the UAV to a given point and along a predetermined trajectory.