Study On Stabilized Platform Control Algorithm Based On KF And FOPID

The photoelectric stabilization platform is the core component of the photoelectric reconnaissance system.The main task is to sensitive and restrain the influence of the carrier attitude change,airflow impacts,motor vibrations,disturbances such as self-friction torque and sensor noise,so as to ensure the stability of the visual axis of the platform.In addition to the influence of the mechanical structure on the stability of the visual axis,the control strategy of the stable platform is also the key to improve the system accuracy and stability.In practice,most of the optoelectronic stabilization platform control methods adopt integer-order PID(Integer Order Proportional Integral Derivative,IOPID)control technology and cannot meet the higher requirements of control performance.The fractional-order PI~?D~?(Fractional Order Proportional Integral Derivative,FOPID)controller has more?and?tunable parameters,so the system control process is more flexible and insensitive to the parameter perturbation.It has better control effect and robustness than the IOPID controller.In this paper,the fractional order control strategy is applied to the photoelectric stabilization platform,and improves the robustness of the platform's gain,realizes the high-precision control of the platform.The following research contents are completed:1)Taking the MD-GD101I two-axis two-frame photoelectric stable platform as the research object,the mathematical model of the pitch axis velocity loop was established based on the experimentally measured data using the system identification method,and the validity of the identification results was tested.2)Based on the establishment of the mathematical model of the photovoltaic stability platform,IOPID control algorithm and FOPID control algorithm are designed for speed loop respectively.Using vector-based gain robust PID parameter tuning method to complete IOPID parameter tuning,using traditional amplitude margin and phase margin method to complete FOPID parameter tuning.Simulation results show that,the system adopts FOPID control algorithm has smaller overshoot,adjustment time,steady-state error and stronger gain robustness than IOPID control algorithm.3)In order to improve the noise suppression capability of the system,a fractional order controller design based on Kalman filter(Kalman Filter,KF)algorithm is studied.For speed and position double closed loop system,IOPID control algorithm based on KF and FOPID control algorithm based on KF are designed respectively.The simulation results show that,the simple IOPID and FOPID control algorithms can not effectively suppress random disturbance.The IOPID control algorithm based on KF and the FOPID control algorithm based on KF have the better control effect and the ability to suppress the disturbance.