Attitude stabilization control of an aerial manipulator using a quaternion-based backstepping approach

Aerial manipulation is a new research area that extends the potential of aerial vehicles, allowing them to physically interact with the environment. Modeling and control of such a system is not a trivial problem due to the coupled dynamics of the aerial vehicle and the robotic manipulator. This paper presents a robust and non linear control system for a Hexacopter equipped with a two-degrees-of-freedom robotic arm. The proposed mathematical model, which is based on a quaternion representation, takes into account the changing inertia and the mass distribution, depending on the arm configuration. We show how the attitude control, using a quaternion-based backstepping, is able to react to the disturbances caused by the arm. In the backstepping design, we introduce a command filter, which contributes to reduce the computational complexity of the algorithm. Finally, we present simulation results that demonstrate the stability of our approach and provide a comparison to a standard PD control.