The Research On Stratospheric Airship Attitude Control Based On Reaching Law Method

Relative to other mount platform stratospheric airship platform mounted as ahigh-altitude has its unique advantages in high air-to-ground observation、timelycommunications、disaster monitoring、military strikes、land resource mapping. It isextensive attention by the world of scholars and research institutions in recent years.The stratospheric airships as one of China’s12th Five-Year period sixteen majorresearch projects is actively studying by China. the study of stratospheric airshipattitude control have been proposed in this context.Stratospheric airship as a mounted platform, it has the characteristics flyingheight, large volume, quality, long life time, moving slowly. The control of it isdifferent from other flying mount platform. This paper in-depth study of stratosphericairship attitude control, get ideal research. The main work of this paper is as follows:(1)Build a mathematical model of stratospheric airship. this paper focuses onstress analysis on the airship, including buoyancy, gravity, aerodynamics, fluid inertiaforce, and analysis airship for the moment. According to the relationship between theprinciples of physics and the parameters determined by the airship’s own structure,established the mathematical model of the airship. For the airship’s own structure, themodel is decomposed into a horizontal lateral and vertical two groups. Finally, thepaper get linearization airship mathematical model by small perturbation method.(2)The paper discussed Reaching law theory, and proposed a new form ofreaching law. This paper introduced the principle of variable structure control,discussed reaching condition and dynamic quality of sliding mode variable structurecontrol, and proved the invariance and the robustness of variable structure control.And then the paper discussed several common reaching law and their advantages anddisadvantages. Finally, introduced the causes of buffeting, the harm of buffeting, themethod of weak buffeting, and proof of the reaching condition of the reaching law.(3)The paper design of the controller and do the control simulation of airshipattitude.The article test and verify airship mathematics model the airshipmathematical model by MATLAB, and get the Simulation graph of airship, proved the system of airship is not controllable in the case without outside control. Next, thepaper design a controller through mathematical analysis, and do a comparisonsimulation analysis between the new forms of approaching law and the general formof reaching law. Simulation results show that, in the airship attitude control, the newforms of approaching law have better anti-buffeting capacity than the average ratereaching law.