Research On Decoupling And Stability Control Technology Of Differential Cable-Driven Platform

With the increasing complexity and multidimensionality of battlefield environment information,the opto-electronic stability platform equipped with high-precision photoelectric detection devices is applied to various equipment systems for tasks such as battlefield environment reconnaissance,target recognition and command tracking.The differential flexible cable-driven stabilized platform combines the cable transmission and the differential driving mothed on the basis of the traditional two-axis two-frame stabilized platform to realize the parallel drive and ensure the servo channel low-altitude return,high rigidity,high transmission efficiency and no lubrication.At the same time,the driving performance and the load-weight ratio are effectively improved,which ensures the compact structure and high adaptability of the platform.This paper proposes the using of torque disturbance observer to realize the suppression of coupling torque within servo channels and the position decoupling by servo channel cooperative control,which are caused by the complex coupling model and differential cable-driven factors.Finally,the decoupling stabilization of terminal azimuth and pitch freedom degree is achieved by the rate gyro direct stabilization method.The main research contents of this paper are reflected in the following aspects:Research and design on platform control circuit and hardware optimization.Taking the actual platform system as the object,the stable target of hardware components needed to achieve is clearly defined.The chip selection is performed according to the control precision requirements,and the FPGA+DSP configuration control circuit is designed and debugged.Both the usability of vital module used for acquisition,signal outputting,parallel communication in FPGA,and DSP drive function are verified in IDE and actual PCB.Analysis of kinematic and dynamic characteristics of differential cable-driven stabilized platform.Based on the analysis result of the composition and differential principle of the platform,the kinematics and dynamics of the transmission mechanism are studied,analyze coupling property with RGA mothed.The advantages and shortages of the classical decoupling control methods based on precise mathematical model are compared,and the overall decoupling strategy is proposed finally.Research on servo channel torque decoupling control design.According to the model features of platform,the torque disturbance observer decoupling scheme is proposed and designed.The decoupling control model is constructed in Matlab/Simulink that verified the scheme has great torque decoupling performance.Then the effectiveness of the torque decoupling observer has been tested on the dSPACE semi-physical simulation platform.Research on servo channel velocity control and platform stability control design.Based on the torque decoupling,the servo channel velocity controller and the dual-channel cooperative control method are proposed to realize the position decoupling of the optical axis.Design the rate gyro directly stabilization loop and the PI controller based on the notch filter.The design of the platform terminator velocity stability controller is realized based on the suppression of the two resonance degrees with different resonant frequencies,the notch filter stability performance and the full decoupling effect are verified by the actual prototype.For the uncertainty of the complex platform system,a type of neural network based PID is proposed,whose feasibility is also verified by Matlab/Simulink.