Advanced Trajectory Control of a Hexacopter UAV: Comparative Analysis of Nonsingular Terminal Sliding Mode and PID Controllers

Abstract

Introduction: This study presents a control strategy for trajectory tracking of Hexacopter UAVs using sliding mode control. The Hexacopter's nonlinear mathematical model is first derived using Newton-Euler's formulation. A nonsingular fast terminal sliding mode controller (NSTSMC) is then developed to enable precise tracking of the flight trajectory, while accommodating variations in orientation angle. To evaluate the controller’s robustness, additional disturbances and chattering reduction techniques are introduced in the tests. The control system's performance, compared with a classical PID controller, is assessed using MATLAB-Simulink simulations. The results demonstrate that the Hexacopter, under the NSTSMC, effectively mitigates disturbances with minimal deviation from the planned trajectory, requiring less effort.