Research On Modeling And Control Method Of Servo Control System For Dual-axis Tracking Turntable

High-precision turntables have become more and more widely used in military,aerospace,and photovoltaic fields.The turntable servo system is generally composed of the turntable mechanical body and operation control system,etc.It is an important part of equipment such as radar,tanks,and radio astronomical telescopes.The main performance indicators include the system's response speed,low-speed operation stability and tracking accuracy,anti-interference ability,etc.In this paper,a dual-axis tracking turntable is taken as the research object,and the stable tracking control algorithm is studied.Because of the existence of disturbance factors such as friction,backlash,mechanical deformation,etc.,the dual-axis tracking turntable system has nonlinear characteristics,and the sliding mode variable structure control algorithm has a better control effect on the nonlinear system.The sliding mode control method can ensure the tracking stability of the control system and has better interference suppression ability.The main content of this article is to study the system stability tracking control problem of dual-axis tracking turntable.The specific work is as follows:Firstly,the single-axis mathematical model of the dual-axis turntable system is established through the mechanism model,and the mathematical model of the dual-axis linkage of the turntable is obtained according to the coordinate transformation.At the same time,the mathematical model of the Lu Gre model for friction disturbance is established.These work are the construction of subsequent control algorithms And the simulation model laid the foundation.Secondly,this paper develops a real-time control system including a host computer for the structure of a dual-axis tracking turntable based on the RTU-BOX real-time simulation platform.Serial communication is realized through Ethernet communication,real-time data is read,and the rotation speed of the dual-axis tracking turntable system is saved,so that it is ready for the experiment of subsequent Lu Gre model parameter identification and control algorithm.Thirdly,based on the established dual-axis tracking turntable servo system model,the PD control method,sliding mode control method based on approach law method and sliding mode control method based on integral switching gain are designed to stabilize the dual-axis tracking turntable and stability tracking issues.Among them,the sliding mode control method based on integral switching gain not only has stronger ability to suppress friction disturbance,but also has better robustness.Simulink simulation and RTU-BOX real-time simulation results prove the effectiveness of the proposed method.