Full Channel Attitude Control for High-speed Aircraft Based on Back-stepping Theory with Observer

In this paper, the full channel attitude controller is investigated for the high speed aircrafts’ cruise phase. Taking the complexity of dynamic system into consideration, the back-stepping method is introduced to reduce the difficulty of controller design, thus it would be much easier to directly design nonlinear controller for subsystem. Besides, one of the problems in designing the control law based on back-stepping is the inevitable "explosion of terms", a novel tacking differentiator based on sigmoid function (STD) is introduced to alleviate the problem, which endows the STD with superior advantages comparing to the traditional differentiator. Furthermore, the observer is applied in outer-loop and inner-loop to estimate the "total disturbance" and some immeasurable state. The estimated value will be the compensation controller integrated into the robust adaptive control law. Lastly, to illustrate the feasibility and superiority of the controller proposed, a series of comparative simulations with nominal and positive/negative perturbation are carried out on a high speed aircraft’s full channel attitude model.