Nonlinear Control of a Fully-Actuated Hexacopter with a Cable-Suspended Load

This paper introduces a novel nonlinear controller to address load transportation problems of fully-actuated un-manned aerial vehicle (UAV). Unlike existing controllers, this controller employs a layered structure, where the outer loop controls the payload and its speed, while the inner loop controls the attitude of the load. Given the full actuation of the UAV, translation and attitude are separated, allowing independent control of the attitude. The stability of the system is verified. Finally, the system's performance is validated in a ROS/Gazebo simulation environment.

I. Introduction

In recent years, unmanned aerial vehicles (UAVs) have been applied in many fields, such as load transportation and delivery. Currently, most UAVs used for load transportation are multirotor UAVs [3]. Traditional co-planar UAVs have actuation properties because their translational and rotational dynamics are coupled. Fully-actuated UAVs are a new type of UAV that can decouple translation and attitude in flight, which has the advantage of transporting loads [1].