Path following control for an under-actuated autonomous airship in constant wind field

In this paper, a path following control method related to the planar motion for an under-actuated autonomous airship is presented. First, the dynamic and kinematic model of the airship is introduced. Planar path-following error equations are proposed based on the virtual guidance law. Then, a nonlinear disturbance observer (NDO) is designed to estimate the constant wind force. A back-stepping method and an approach angle are introduced to design the path-following controller. The controller designed is simpler compared with the traditional back-stepping method and the approach angle is helpful to adjust the transient maneuver during path approach phase. In addition, it overcomes the singularity problem. The stability of the system is proved. Simulation results illustrate the effectiveness of the proposed controller.