Application Of ADRC In Aerial Reconnaissance Camera Position-angle Speed Control System

In recent decades,aerial imaging and measurement technology has gradually developed.As a new technology,aerial imaging and measurement technology includes many disciplines.It uses airborne optical systems and optocouplers to reconnoiter and measure ground scenery information.It is mainly used for reconnaissance of enemy ground target area before war and evaluation of our military attack after war.It is one of the important means to obtain military information,and it is of great significance to the development of our military and national defense fields.Aerial reconnaissance camera has become one of the main aerial imaging means because of its flexibility,high timeliness and strong purpose.When the aerial reconnaissance camera is working,due to the movement of the aircraft,the relative movement of the line of sight and the target point occurs,thereby generating forward image shift.Therefore,this requires compensation for the line of sight.In addition,the working environment of aerial reconnaissance camera is complex and changeable.And,the change of attitude and the vibration of the engine will bring huge and unpredictable external disturbance to the system,which will lead to the decline of resolution of the image taken by the jitter of the line of sight.Also,the aerial reconnaissance camera also has some non-linear problems such as dead zone,saturation and non-uniform friction when it is running.So,it is difficult to obtain the accurate model of the controlled object.The traditional PID control method can not estimate the external disturbance of the system,and can not deal with the internal disturbance caused by the change of system parameters,so the control effect is not ideal.In this paper,a long focal length panoramic linear array TDI-CCD aerial reconnaissance camera is taken as the research object to control the speed of the position-angle system,to compensate the line of sight.Analyzed the system performance indicators.The transfer function of the position-angle speed system of the aerial reconnaissance camera is measured.And an active disturbance rejection controller is designed for the system,including tracking differentiator,extended state observer and state error feedback control law.And the simulation experiment is carried out to verify the rapidity of active disturbance rejection control method and its ability to restrain internal disturbance and external disturbances of the system.The results show that the system is stable within 0.05 seconds when the input is step signals with amplitude of 0.1°/s.The error of system is less than 0.02°/s.The simulation results show that whether internal disturbances or external disturbances,active disturbance rejection control method has good disturbance rejection ability.Finally,experiments are carried out on the experimental platform.The active disturbance rejection controller designed in this paper meets the requirement of system performance indicators.