Sliding mode backstepping control for variable mass hexa-rotor UAV

Abstract

The mass of an Unmanned Aerial Vehicles (UAV) alters while picking up or dropping off a mass. The variable mass will deteriorate the control performance of the UAV. This deteriorated control performance generates unstable motor output and leads to power loss. To solve this problem, a mathematical model considering variable mass in real time is proposed in this paper. Based on the established model, taking position and attitude tracking control problem into consideration, a robust control scheme is then designed via Sliding Mode Control (SMC). Backstepping method is used to track the attitude of UAV underactuated system. The proposed controller adapts to the change of mass to control the UAV and stabilizes the position error and the attitude tracking error along the desired trajectory for the position tracking. Stabilized position, attitude and reduced errors are verified through simulation. © 2020 Institute of Control, Robotics, and Systems - ICROS.