Research On Conventional Control Strategy And Wind And Disturbance Rejection Control Of Unmanned Airship

Airship is a kind of aerial vehicle flying by buoyancy and propulsion.Compared with aircraft,airship has low manufacturing cost,low noise,long endurance and certain load capacity.Due to its good economic applicability,it has a good application prospect in the national defense and economic fields.Especially for the vast and complex terrain environment of China's territory,the airship is particularly suitable for performing survey,communication and transportation tasks.However,due to its large size,the airship has poor wind resistance and is susceptible to environmental influences such as air pressure and temperature.The control is complicated and it is difficult to ensure its safety.In order to make up for this shortcoming,the development trend of foreign airships has changed from the traditional buoyancy and rudder surface control to the structural layout of multiple sets of thrust vectors.Domestic unmanned airships have less research on this aspect.This paper is a new shape multi-vector thrust airship.Two attitude control schemes are designed to keep the airship stable in complex environments,so that it can complete the mission well.This paper mainly carried out the following work.Firstly,a new shape airship structure is introduced.The traditional aircraft modeling method is used to establish mathematical modeling for the airship.Based on this,the research on control design is carried out.Secondly,the state response of airship under different disturbances and inputs is simulated,and the longitudinal and horizontal coupling and maneuverability are analyzed.Based on this,the reasonable distribution of multi-vector thrust is carried out,and the conventional PID control method is designed.The improved method of variable speed integral gain is proposed to avoid the contradiction between fast response and error-free control.The simulation results show that the method has good control effect.Then it is considered that there will be control deviation due to aerodynamic coefficient deviation and wind disturbance during the flight of the airship,and the robustness of the conventional PID control under the interference condition is not strong enough.In response to this situation,the linear auto disturbance rejection controller is used to observe and compensate the interference,and the control effect is verified under the wind and disorder wind field.Then,for the tuning problems of the previous two controllers,the gray wolf optimization algorithm is used to optimize the controller parameters,and the deflection of the rudder surface is considered into the objective function to improve the rudder bias response.Compared with the manual adjustment controller parameters,the optimization method is convenient and the control quality is improved,which is more in line with the actual engineering needs.The simulation results verify the effectiveness of the gray wolf algorithm in controller optimization.The last part summarizes the full text,and puts forward the shortcomings in the current research work and the direction that needs improvement.