Research On Servo Control System Of Shipborne Stabilized Platform

With the level of development of national defense weaponry, a higher qualification is proposed for marine equipments’ ability to steady aim and track targets. The demand of high precision and fast response stabilized tracking platform is becoming more and more urgent. This paper conducts a research on servo control system of shipborne stabilized platform.Firstly, three closed-loop servo control system model based on DC torque motor is built. According to the system performance requirements, current loop, speed loop and position loop controllers are designed. Sliding mode switching function and sliding mode controller are designed. Boundary layer method is used to weaken the chattering of sliding mode control. The simulations verify that sliding mode controller has better robustness and boundary layer method has a significant inhibitory effect on the chattering of sliding mode control.Secondly, the servo control equipment of two-axis shipborne stabilized platform is designed, including ARM core board, control board, driver board and filter inductors. PCB board is designed in Altium Designer09. The programs and algorithms are programed in Keil μVision5. PC program and interface, including debug module, analysis module and data processing module, are designed in Lab VIEW environment for the servo control equipment.Finally, experiments are conducted on one-axis turntable and two-axis turntable respectively. Servo control has no static error on one-axis turntable and two-axis turntable by PID algorithm. While following a sine, which period is 10 s and amplitude is 5°, the maximum error of the servo control is approximately 0.675° on one-axis turntable, approximately 0.765° on azimuth axis and 0.315° on pitch axis of the two-axis turntable. Servo control has chattering with amplitude of 0.0045° by sliding mode algorithm. While following the sine mentioned above, the maximum error is approximately 0.36° on one-axis turntable. Stribeck friction model parameters and moment of inertia are measured by measurement module on one-axis turntable, which achieves the expected design requirements.