Research On Control Strategies Of Gyro Stabilized Platform

Gyro stabilized platform can isolate disturbance from the carrier, making the electro-optical sensors'line-of-sight (LOS) point to a fixed inertial space and guaranteeing the quality of image detection. With the development of modern military technology, the requirements for tracking ability of weapons and stabilization of electro-optical sensors'LOS are higher. Various kinds of advanced platform have come into being.Firstly, the paper summaries the development of gyro stabilized platform at home and abroad. Based on the key problems in the design, the current control strategies of gyro stabilized platform are analyzed. Then, according to the existing research results and design specifications, an overall scheme of gyro stabilized platform is presented. Also, the paper analyzes mechanical and electrical structure of the platform and discusses the selection of components. The mathematical model of single-axis control system is established.Secondly, the disturbance torques which are caused by regular motion of base are deeply analyzed, and the mathematical expression of various disturbance torques is deprived. Due to the existing of disturbance torques, the platform becomes a non-linear system, and it is difficult to guarantee tracking performance using conventional PID control method. In this case, this paper adopts the active disturbance rejection control (ADRC) algorism to compensate the friction torque which is the main disturbance of the platform. The simulation results are compared between ADRC and PID, and the results show that the ADRC controller has stronger robustness and is superior to PID controller.Based on ADRC's sensitivity to system's uncertainty and output measurement noise, the robust control strategy is presented. The robust controller is designed by using mixed sensitivity optimization method, and the simulation results are given. After comparing with PID control and ADRC, we can see that robust control is superior to them on the aspects of overcoming system uncertainty and suppressing output measurement noise.Finally, according to the current experiment condition, the paper gives the test results of the gyro stabilized platform system. The results show that the basic function of system is realized.