Nonlinear Modelling and Robust Backstepping Control of a Quadcopter in Aggressive Maneuvering

Abstract

Quadcopter unmanned aerial vehicles (UAVs) are vehicles with 4 propellers, capable of taking off and landing vertically (VTOL) and hovering in the air. In recent years, developments in hardware, software, battery, sensor and camera technologies have facilitated the production processes of quadcopters and led to diversified usage areas. Quadcopters are used in many different areas such as fighting natural disasters, combating terrorism, border patrol, surveillance, search and rescue and cargo transportation. Quadcopters need to be fast and able to make aggressive maneuvers, when performing these tasks. In this study, nonlinear modelling of the quadcopter was carried out and a robust backstepping controller was designed, which allows the quadcopter to make harsh maneuvers. The quadcopter has been tested under triangular, sinusoidal and sawtooth maneuvers. A 10% parameter uncertainty was also implemented to the mass (m) m ) and inertial moments (Ix, Ix , Iy and Iz ) of the quadcopter during aggressive maneuver tracking. The backstepping controller proposed in the study was compared with classical PID and Lyapunov-based control methods. A comprehensive robustness examination was realized by obtaining time response of all controllers, while performing harsh maneuvers. Thus, the superiority of backstepping control under aggressive maneuvers has been shown.