Random trajectory tracking for low altitude airship

In this paper, a design scheme of backstepping controller based on energy function is presented for a low altitude airship trajectory tracking control with stochastic disturbance. First, the dynamic model of six degrees of freedom system in hybrid coordinate system is established. Then, the stochastic disturbance of airflow to airship is regarded as the second order moment process, and the stochastic dynamic equation of low altitude airship is obtained. The trajectory tracking controller with design parameters is obtained by using vectorial backstepping method. Through the theoretical analysis, all of the signals in system are proven to be bounded, while the output tracking error converge to small neighborhood of the origin. Modeling in hybrid coordinate system simplifies the transformation matrix between position and velocity of the airship, which makes the controller simpler. Compared with the controller design scheme based on other modeling methods, it is easier to apply to practical engineering.