Research On Attitude Control System Of Three-axis Stable Platform Based On ADRC

Three-axis stable platform is a device that can obtain stable plane on a moving object.By removing the influence of angular motion of carrier on the equipment on the platform,the equipment on moving object can realize stability in inertial space.It has been applied in industrial fields such as robot control system and civil fields such as aviation,navigation,vehicle photography,etc.First of all,the working principle of the three-axis stabilized platform frame is analyzed based on the existing rotating platform,and the mathematical model of the single-axis stabilized platform is built by collecting the actual data,then the coupling model of the three-axis stabilized platform is established.What's more,on the basis of analyzing the causes of buffeting problem of three-axis stabilized platform,a stable platform control system based on Active Disturbance Rejection Control(ADRC)is designed,and the parameters of each component of ADRC are tuned using the separation principle,and the tuning rules are summarized.Extended State Observer ESO(Extended State Observer ESO)is the core of the control system.A mathematical model of a specific system is established to obtain its state gain matrix L.The simulation curve shows that the state observer can observe the state of the control system.A linear combination link based on error feedback is added to ADRC control strategy.Compared with ADRC based on non-linear combination of error feedback,the former avoids the sudden change of control signal in the control system of three-axis stabilized platform,and makes the output signal of the control system more continuous and smooth.The mathematical model of DOB-based stabilization platform control system is designed,and how to select the low-pass filter Q(s)of DOB to filter the measurement noise and gyro noise effectively is analyzed.Finally,the control performance of the two active disturbance-resistant control technologies on the stabilization platform is analyzed.Although both methods can improve the robustness of the control system,compared with the control system based on the improved ADRC stabilization platform,the control system based on the PID+DOB stabilization platform has a single noise processing,and can not be separated from the compensation of the PID controller for the system,but based on the improved ADRC stabilization platform.The control system of the stabilized platform can observe model mismatch,observe disturbance,and deal with errors remarkably.It has better robustness and stability accuracy.The simulation results show that compared with the traditional control method and ADRC-based control system,the stability error accuracy of the control system based on improved ADRC is improved by an order of magnitude.It is effective to adopt the linear combination of errors to obtain more stable and suitable control effect for engineering application.The experiment also proves that the stability of the control system based on improved ADRC is greatly improved.