The Active Disturbance Rejection Control Technology Of Photoelectric Tracking And Directing Pod Based On DSP

The photoelectric tracking pod is not only a weapon of modern warfare,it has the ability to capture,aim,and track the target at a long distance,provide oneself with accurate directional positioning,and the ability to detect the enemy first and attack outside the area,but also in the civilian field,it has broad market value for land exploration,power inspection,urban planning,etc.carried on the drone.All of these have put forward harsh requirements for the optical tracking and pointing pod,which can effectively isolate the interference from external disturbances and internal disturbances on the visual axis,and stably point to the target.With the diversification and complexity of the application environment and scenarios,the control accuracy,stability,and anti-interference ability of the optoelectronic tracking pod are becoming higher and higher.This thesis takes the two-axis and two-frame photoelectric tracking and pointing pod as the research object,with the goal of improving the stability accuracy,anti-interference ability and robustness,and carrying out the research on the active disturbance rejection control technology of the photoelectric tracking and pointing pod.Firstly,establish a mathematical model for the servo control system of the photoelectric tracking pod.Through the structure of the two-axis and two-frame photoelectric tracking and pointing pod,the kinematic analysis of the carrier and the sight axis of the pod,the controllability of the pod based on the Euler transformation matrix is proved;the work of the photoelectric tracking and pointing pod is explored Based on the principle and analysis of the factors that affect the accuracy of the sight axis stability,the analytical modeling and system identification methods of the mathematical model construction of the servo control system of the photoelectric tracking and pointing pod gyro stabilized platform were carried out.The system identification method is used to identify the second-order transfer function model of the gyro stabilized platform.Secondly,combining the tracking differentiator and the fal function,an improved PID control strategy is proposed and applied to the second-order transfer function model control identified above.Compared with the control performance of the classic PID control strategy,the simulation verifies the improved PID control strategy.The control strategy has the advantages of excellent dynamic performance and high stability and precision.Then,In view of the strict dependence of the design of classic PID and improved PID controllers on the model of the controlled object in the actual working environment,and the difficulty of obtaining an accurate model of the controlled object,and it is difficult to obtain the accurate model.Combined with the active disturbance rejection control,which has almost no model dependence and the advantages of active disturbance rejection,the research on the active disturbance rejection control strategy of the optoelectronic tracking pod control is carried out.It mainly includes exploring the principle of active disturbance rejection control.In addition,Carried out the speed loop second-order active disturbance rejection controller design based on nonlinear and linear active disturbance rejection control,parameter tuning method research,as well as the stability,immunity and robustness of the photoelectric tracking and pointing system,etc.Simulation analysis.There is the disadvantage that the second-order active disturbance rejection controller cannot estimate the angular velocity disturbance at the output end of the visual axis,which seriously affects the stability accuracy and tracking performance of the visual axis of the photoelectric tracking and pointing pod.Combining the cascade control,a cascade linear active disturbance rejection control strategy is proposed,and a two-stage cascade linear active disturbance rejection controller of speed loop is designed,and stability verification are realized and parameter tuning.The simulation shows that the system has the advantages of strong anti-interference ability,high stability and precision,and good robustness.Finally,Based on the TMS320F28335 digital signal processor,complete the overall hardware circuit design and program design of the servo control system,A DSP-based photoelectric tracking and pointing pod physical verification platform was built.Discretize the two-stage cascade linear active disturbance rejection controller and apply it to the motor control of the photoelectric tracking and pointing pod gyro stabilized platform.The experimental results show that the cascade linear active disturbance rejection controller has the advantages of excellent dynamic characteristics,small tracking error,strong anti-interference ability,high stability and accuracy,and good robustness.