Comparison of control systems for multirotor UAV [in Ukrainian]

This paper investigates the problem of quadcopter altitude stabilization under external disturbances, particularly wind gusts. For the analysis, a mathematical model of a multirotor UAV based on the Newton–Euler equations for a rigid body with six degrees of freedom (6-DOF) was used. The study was carried out in the MATLAB/Simulink environment, which made it possible to simulate the operation of a closed-loop control system under realistic environmental influences. The aim of the work is to compare three approaches to altitude control: the classical PID controller, the fuzzy PD controller (fuzzy-PD), and the optimal Linear Quadratic Regulator (LQR). For each strategy, tuning, simulation, and analysis of transient responses were performed. The effectiveness was evaluated using key indicators: settling time, overshoot, and root mean square error (RMSE) under wind disturbances. The obtained results showed that the fuzzy-PD controller provides the best overall control quality: the fastest transient response, minimal overshoot, and the lowest error under disturbances. The LQR regulator demonstrated high robustness and a balance between speed and accuracy, significantly outperforming the classical PID in all criteria. The PID controller served as a basic benchmark but exhibited the highest sensitivity to wind effects. Thus, the study confirms the feasibility of using adaptive and optimal approaches (fuzzy-PD and LQR) to ensure reliable quadcopter altitude stabilization in a changing environment, which is practically important for aerial photography, monitoring, inspection, and search-and-rescue missions.